The correct answer is "freezing is exothermic because as water bonds into ice, the energy from bond formation is released and heats up the surrounding environment."
option B.
What happens to substance when it phase changes?When a substance undergoes a phase change, such as from a liquid to a solid, energy is either released or absorbed. Freezing is a phase change in which a liquid transforms into a solid.
During freezing, energy is released by the substance as it loses heat to its surroundings. This energy is released because the particles of the liquid slow down and come together to form the more ordered structure of a solid, which releases heat to its surroundings. Therefore, freezing is an exothermic process.
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The complete question is below:
Is freezing an endothermic or exothermic process? Choose the correct answer and explain your reasoning.
(a) Freezing is exothermic because as water bonds into ice, the energy from bond formation is released and heats up the surrounding environment.
(b) Freezing is exothermic because as water bonds into ice, the energy from bond formation is released and heats up the surrounding environment.
(c) Freezing is exothermic because as water bonds into ice, the bonds absorb energy from the environment in order to change states.
(d) Freezing is exothermic because as water bonds into ice, the bonds absorb energy from the environment in order to change states.
(e) Freezing is endothermic because as water bonds into ice, the energy from bond formation is released and heats up the surrounding environment.
(f) Freezing is endothermic because as water bonds into ice, the energy from bond formation is released and heats up the surrounding environment.
(g) Freezing is endothermic because as water bonds into ice, the bonds absorb energy from the environment in order to change states.
(h) Freezing is endothermic because as water bonds into ice, the bonds absorb energy from the environment in order to change states.
a metal will be placed in fire and an electron will absorb enough energy to be promoted to a higher energy state. what do we call this higher energy state?
When a metal is placed in the fire and an electron absorbs enough energy to be promoted to a higher energy state, this higher energy state is referred to as the excited state.
An excited state is a state of a molecule or atom in which it has absorbed sufficient energy to move an electron from its current orbital to a higher orbital. This state is referred to as the excited state, and the electron that has been elevated to a higher energy level is said to be in an excited state.
The reason behind the electron's promotion to a higher energy state when a metal is placed in fire is that the heat causes the electrons to absorb energy, which causes them to move to a higher energy state. When electrons move to higher energy states, they release energy in the form of light, heat, or other radiation.
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a saturated hydrocarbon has the maximum amount of hydrogens attached to the carbon skeleton. group of answer choices true false
True, a saturated hydrocarbon has the maximum amount of hydrogens attached to the carbon skeleton.
What is a hydrocarbon?Hydrocarbons are organic molecules that are made up of only carbon and hydrogen atoms. They may be composed of chains of various lengths, rings of various sizes, or a combination of both. The simplest hydrocarbons, such as methane (CH4), ethane (C2H6), and propane (C3H8), are gaseous at room temperature, whereas larger hydrocarbons are liquids, such as hexane (C6H14), or solids, such as hexadecane (C16H34).
Unsaturated hydrocarbons have carbon-carbon double or triple bonds in their structures, indicating that they are not completely saturated with hydrogen atoms. These hydrocarbons are commonly referred to as alkenes or alkynes, respectively. Alkenes have one double bond, whereas alkynes have one triple bond.
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i. if you conducted this coupling step under acidic conditions, how would you expect the reaction rate to be affected?
If you conducted this coupling step under acidic conditions, you expect the reaction rate to be affected because at low pH values, the carboxylic acid is transformed into a more electrophilic species, which is easily attacked by the nucleophile, and the yield of the amide bond would be high.
In organic synthesis, coupling reactions are common, and they include the combination of a nucleophile with an electrophile to form a covalent bond. The coupling reaction between a carboxylic acid and an amine is a straightforward way to synthesize an amide in the presence of an activating agent (a molecule that can increase the electrophilicity of the carboxylic acid).
It is worth noting that there are various methods for synthesizing amides, including chemical and enzymatic methods. Coupling reactions are the most frequent chemical methods used for the synthesis of amides.
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What is the nature of the bond indicated?
A. Nonpolar Covalent
B. Polar Covalent
C. Ionic
D. Metallic
The nature of the bond indicated in the diagram above would be the nonpolar covalent bond. That is option A.
What is a Nonpolar Covalent bond?A Nonpolar Covalent bond is defined as the type of chemical bond that is formed when electrons are shared equally between two atoms.
While polar covalent bond is defined as the type of chemical bond that is formed when electrons are shared unequally between two atoms.
For example, molecular oxygen (O2) is nonpolar because the electrons will be equally distributed between the two oxygen atoms.
Therefore the type of bond that is indicated in the diagram above is a nonpolar covalent bond.
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a chemist determined by measurements that moles of magnesium participated in a chemical reaction. calculate the mass of magnesium that participated in the chemical reaction.
Answer : The molar mass of magnesium is 24.305 g/mol
To calculate the mass of magnesium that participated in the chemical reaction, you need to know the number of moles of magnesium and the molar mass of magnesium. The molar mass of magnesium is 24.305 g/mol. Multiply the number of moles of magnesium by the molar mass of magnesium to calculate the mass of magnesium that participated in the chemical reaction.
For example, if you were given that the number of moles of magnesium is 0.25 moles, then you can calculate the mass of magnesium by multiplying 0.25 moles by 24.305 g/mol. This gives a result of 6.076 g of magnesium that participated in the chemical reaction.
To sum up, calculating the mass of magnesium that participated in the chemical reaction requires knowing the number of moles of magnesium and the molar mass of magnesium. The molar mass of magnesium is 24.305 g/mol, and you can calculate the mass of magnesium that participated in the chemical reaction by multiplying the number of moles of magnesium by the molar mass of magnesium.
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it is fine to enter an area where there is a chemical spill as long as you are very careful. true or false?
The statement "it is fine to enter an area where there is a chemical spill as long as you are very careful" is False. because A chemical spill refers to the uncontrolled release of one or more hazardous substances.
A chemical spill refers to the uncontrolled release of one or more hazardous substances, which can include liquids, gases, or solids, which might pose a significant threat to the environment and human health. The person responsible for a chemical spill is responsible for managing, containing, and cleaning up the hazardous material to prevent environmental or public health damage.
Following a chemical spill, there is a protocol to be followed to guarantee that no harmful substances have been released into the environment that may cause harm to the public. The presence of toxic chemicals in a confined area poses a significant threat to human health, making it hazardous to enter that location. Even if the spill is small, entering an area where a chemical spill has occurred is hazardous. The contamination may disperse through the air, and you may inhale it or the substance may adhere to your clothing and skin, putting you at risk. You should not go near a chemical spill if you are not wearing appropriate protective gear. This is because it is not advisable to enter an area where there is a chemical spill.
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10cm³ of co was mixed with 15cm³ of oxygen and exploded. After cooling to the original temperature, the volume was 20cm³; after shaking with acqueous sodiumhydroxide the volume was reduced to 10cm³. Show that this figures agree with Gay Lussac's law
In this reaction, 10 cm³ of CO is mixed with 15 cm³ of oxygen. After the reaction, the volume of the product is 20 cm³. When shaken with aqueous sodium hydroxide, the volume is reduced to 10 cm³. This agrees with Gay Lussac's Law.
According to Gay Lussac's Law, the ratio of the volumes of the reactants and products of a reaction are constant when pressure and temperature are held constant. In this reaction, 10 cm³ of CO is mixed with 15 cm³ of oxygen. After the reaction, the volume of the product is 20 cm³. When shaken with aqueous sodium hydroxide, the volume is reduced to 10 cm³. This agrees with Gay Lussac's Law since the ratio of the initial reactant volumes (10 cm³ to 15 cm³) is the same as the ratio of the final product volumes (20 cm³ to 10 cm³).
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in the experiment where o2 consumption is measured with a respirometer how is a constant volume achieved?
by use identical respirometers. An intermediary in this process is pyruvate.
What kind of process uses pyruvate as an intermediary?Pyruvate is a crucial intermediary in several metabolic processes, including gluconeogenesis, fermentation, cellular respiration, fatty acid production, etc. Pyruvate is created near the conclusion of the glycolysis process. Through Kreb's cycle, pyruvate gives energy to living cells.
Is pyruvate a metabolic intermediary in all processes?Pyruvate is a crucial intermediate that can be employed in a number of anabolic and catabolic pathways, including as oxidative metabolism, glucose re-synthesis (gluconeogenesis), cholesterol synthesis (de novo lipogenesis), and maintenance of the tricarboxylic acid (TCA) cycle flow.
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A biochemist wanted to adjust the of of a buffer solution composed of ( ) and , by adding moles of. (assume the volume of the solution is not affected by this addition. ) determine the of the resulting solution:
The pH value of the resulting solution assume the volume of the solution is not affected by this addition is 3.283.
The pH scale determines how acidic or basic water is. The range is 0 to 14, with 7 representing neutrality. Acidity is indicated by pH values below 7, whereas baseness is shown by pH values above 7. In reality, pH is a measurement of the proportion of free hydrogen and hydroxyl ions in water.
In this Question, HF is a Weak Acid and RbF is a weak Base - HNO3 is a strong acid.
HF reaction in aqueous medium
HF + H2O --------- H3O+ + F -
RbF + H2O ---- Rb+ + F -
pH (Original) = pKa + log ( [salt ] / [Acid] )
We donot need to calculate pH original -which is for the original solution before adding the strong acid.
HF is a weak acid - so in a buffer solution its dissociation is negligible - so it does not affect the H+ ion concentration much.
When a 0.012 mol of HNO3 is added to the buffer solution , it dissociates in H+ and NO-3 .
H+ ions dissociated from the Acid react with F - and produce HF . As a result the acid concentration will increase to the extent of 0.012 mol and the salt concentration reduces by the same extent - 0.012 mol.
So the formula for New pH changes to
pH (New) = pKa + log ( [salt ] - 0.012 mol / [Acid] + 0.012 mol)
Here , 0.012 mol are added to 281 mL solution,
Concentration of HNO3, M = number of moles / Vol in litres
= 0.012 mol / 281 mL
= 0.012 mol / 281 / 1000
= [0.012 mol x 1000] / 281 L = 0.043 M
As pKa = -log(Ka) ,
Given [salt ] = 0.480 M , [Acid] = 0.318 M
= - log(Ka) + log [ (0.480 M - 0.043 M) / (0.318 M + 0.043 M) ]
= - log (6.31 x 10-4 ) + log ( 0.437 / 0.361)
pH (New) = 3.20 + 0.083 = 3.283.
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Complete question:
A biochemist wanted to adjust the pH of 281 mL of a buffer solution composed of 0.318 M HF and 0.480 M RbF (K, = 6.31e - 04) by adding 0.012 moles of HNO3. Determine the pH of the resulting solution: pH number (rtol=0.02, atol=1e-08)
prior knowledge questions (do these before using the gizmo.) what important gas do we take in when we breathe?
Answer: The important gas that we inhale when we breathe is oxygen (O2).
It is necessary for the process of respiration. Respiration is a vital process that takes place in all living cells, including human cells. In this process, glucose (sugar) and oxygen are converted into energy (ATP), carbon dioxide (CO2), and water (H2O).
During the process of inhalation, the air enters the body through the mouth and nose. Afterward, it moves down the trachea and then into the lungs. Once inside the lungs, oxygen molecules pass through the thin walls of the capillaries and into the bloodstream, where it is transported to the rest of the body. Oxygen is essential for the proper functioning of the body.
It is used by the cells to produce energy, which is used to power various biological processes. Without oxygen, our cells would not be able to function, and we would die.
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a 78.0 ml 78.0 ml portion of a 1.70 m 1.70 m solution is diluted to a total volume of 218 ml. 218 ml. a 109 ml 109 ml portion of that solution is diluted by adding 115 ml 115 ml of water. what is the final concentration? assume the volumes are additive.
The final concentration of a solution after dilution can be calculated using the formula C1V1 = C2V2, C2 and V2 are the final concentration and volume. The final concentration of the solution after the second dilution is 0.309 M.
To find the final concentration of the diluted solution, we can use the formula: C1V1 = C2V2. Where C1 is the initial concentration, V1 is the initial volume, C2 is the final concentration, and V2 is the final volume. First, we dilute a 78.0 ml portion of a 1.70 M solution to a total volume of 218 ml. Using the formula, we can find the final concentration: [tex](1.70 M)(78.0 ml) = C2(218 ml)[/tex]
[tex]C2 = (1.70 M)(78.0 ml) / (218 ml)[/tex]
[tex]C2 = 0.610 M[/tex]
[tex]C1V1 = C2V2[/tex]
[tex](0.610 M)(109 ml) = C2(109 ml + 115 ml)[/tex]
[tex]C2 = (0.610 M)(109 ml) / (109 ml + 115 ml)\\\C2 = 0.309 M[/tex]
Therefore, the final concentration of the solution after the second dilution is 0.309 M.
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during chemical weathering, sodium is released as dissolved ions and transported to the ocean, where:
Answer: During chemical weathering, sodium is released as dissolved ions and transported to the ocean, where it increases the salinity of the seawater.
Salinity is a measure of the amount of salt in seawater. The greater the salinity, the more salt there is in the water. The salinity of seawater is expressed in parts per thousand (ppt). There are about 35 ppt of salt in seawater.
Chemical weathering is the breakdown of rocks by chemical reactions, resulting in the formation of new minerals. Water is the most common medium for chemical weathering because it can dissolve many minerals. Carbon dioxide, oxygen, and organic acids are also involved in chemical weathering.
Sodium is a common element in minerals that are subject to chemical weathering. When rocks weather, sodium ions are released into the water. Rivers and streams transport these dissolved ions to the ocean, where they accumulate over time.
This is why seawater has a high concentration of sodium ions. Sodium is also introduced into seawater through underwater volcanoes and hydrothermal vents.
Sodium is important for many organisms that live in the ocean. It is an essential nutrient for marine animals, and it plays a role in regulating the body fluids of fish and other aquatic animals. Sodium is also important for maintaining the pH of seawater.
The concentration of sodium in seawater can also have an impact on ocean currents and the movement of water around the world.
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100cm3 of a gas at 27degree Celsius exert a pressure of its volume is increased to 200cm3 at 127 degrees Celsius
Answer: 100cm3 of gas at 27°c exert a pressure of 750mmHg. Calculate its pressure if it's volume is increased to 250cm3 at 127°c? In Chemistry
Explanation:
as electrons are passed down an electron transport system, choose one: a. h2o is produced. b. the electrons are also pumped across a membrane. c. protons are pumped across a membrane. d. nadh is produced.
As electrons are passed down an electron transport system protons are pumped across a membrane.
The correct answer is option C.
When electrons pass through the electron transport chain, they lose energy. As low-energy electrons break down oxygen molecules and produce water, high-energy electrons from NADH or FADH2 complete the chain. The electron transport pathway produces three molecules of water for every three carbon sugars broken down during aerobic respiration.
This means that when six carbon sugars are broken down, six molecules of water are produced. The end products of electron transport include NAD+, FAD, water, and protons. Since protons are propelled through the crystal membrane by the free energy of electron transport, they exit the mitochondrial matrix.
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does the response of temperature in the atmosphere to an increase in co2 always stay the same as the co2 is progressively increased?
Yes, the response of temperature in the atmosphere to an increase in CO2 is generally consistent. As more CO2 is added to the atmosphere, it traps more heat from the sun, leading to a gradual increase in temperature. This phenomenon is known as the greenhouse effect.
The response of temperature in the atmosphere to an increase in CO2 does not always stay the same as the CO2 is progressively increased. It changes depending on various factors. This statement is backed up by scientific evidence.CO2 is known as a greenhouse gas that warms the Earth's atmosphere by absorbing and radiating energy within the infrared range.
When there is more CO2 in the atmosphere, there will be more radiation absorbed and radiated, resulting in a temperature increase.
Therefore, as the concentration of CO2 rises, the temperature of the Earth's atmosphere should also rise. However, the relationship between CO2 and temperature is not that simple.
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Which water is distributed on Earth from the greatest to the least
The water distributed on Earth from the greatest to the least is saltwater, freshwater, and frozen water.
Saltwater occupies 97.5% of Earth's total water. Freshwater occupies only 2.5% of Earth's total water. This freshwater is found in different forms, such as rivers, lakes, underground, and glaciers. Only 0.3% of freshwater is found in rivers and lakes, while 30% is stored underground. The rest of freshwater is stored in glaciers and polar ice caps.
The frozen water found on Earth is 1.7% of the total water. It is found in glaciers, ice caps, and snow cover around the poles. The water cycle is a natural process that allows water to move from one place to another on Earth. It is also called the hydrologic cycle. It involves the movement of water between the earth, air, and ocean.
Water evaporates from the surface of the earth, which forms clouds. The clouds then precipitate as rain, snow, or hail. This precipitation may fall on the land and join rivers and lakes, or it may seep into the ground and form underground water. The underground water may then resurface as springs or streams, which then join rivers and lakes.
The water cycle helps to purify water and replenish freshwater resources on earth. It also helps to regulate the Earth's temperature by absorbing heat during the day and releasing it at night.
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How much KNO3 will dissolve in 200 grams H2O at 70 C
The red line shows that at 70 °C, 200 g of water will be saturated with about 140 g or potassium nitrate.
How does solubility in 100 grammes of water become calculated?This mass of a compound would be divided by mass of the solvent, and then divided by 100 g to determine its solubility. This calculation will give the solubility of the substance in g/100g.
How does the temperature affect KNO3's solubility in water?The curves demonstrate that when temperature rises, solubility of any and all three solutes increases. The most noticeable increase in solubility is for potassium nitrate, which goes from about 30 g per 100 g of water from over 200 grams per 100 grams of water.
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citric acid contains 37.51% c, 4.20% h, and 58.29% o by mass. what is the empirical formula of this compound?
The empirical formula of the given compound can be determined as follows the CHOS or C3H4O3.
According to the given data, the compound citric acid contains 37.51% C, 4.20% H, and 58.29% O by mass. So, let's assume that we have 100 g of citric acid, and then, we can find the masses of each element present in it: Mass of carbon = 37.51 gMass of hydrogen = 4.20 g. Mass of oxygen = 58.29 g.
Next, we need to convert the masses into the number of moles using the molar masses of the elements. The molar mass of carbon = 12.01 g/mol, Number of moles of carbon = 37.51 g / 12.01 g/mol = 3.124 molMolar mass of hydrogen = 1.01 g/molNumber of moles of hydrogen = 4.20 g / 1.01 g/mol = 4.158 molMolar mass of oxygen = 16.00 g/molNumber of moles of oxygen = 58.29 g / 16.00 g/mol = 3.643 follow, we need to find the simplest whole-number ratio of these moles by dividing them by the smallest number of moles, which is 3.124 mol: Carbon = 3.124 mol / 3.124 mol = 1Hydrogen = 4.158 mol / 3.124 mol = 1.33 ≈ 1Oxygen = 3.643 mol / 3.124 mol = 1.17 ≈ 1So, the empirical formula of citric acid is CHOS or C3H4O3.
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Given this equation (linked in screenshot), which of the following is true if 4.53 moles of C6H14 completely reacts with excess oxygen?
A) 0.755 moles CO2 and 0.162 moles H2O will be formed.
B) 27.1 moles CO2 and 31.7 moles H2O will be formed.
C) 12 moles CO2 and 14 moles H2O will be formed.
D) 54.4 moles CO2 and 63.4 moles H2O will be formed.
The correct answer is option D: 54.4 moles CO₂ and 63.4 moles H₂O will be formed when 4.53 moles of C₆H₁₄ completely reacts with excess oxygen.
What is a chemical reaction?
A chemical reaction is a process that leads to the transformation of one chemical substance to another chemical. It involves breaking and forming of chemical bonds between atoms to create new molecules or compounds.
According to the balanced equation given, 2 moles of C₆H₁₄ react with 19 moles of O₂ to produce 12 moles of CO₂ and 14 moles of H₂O.
Therefore, for 4.53 moles of C₆H₁₄ , the amount of O₂ required for complete reaction would be:
(19/2) x 4.53 = 42.9 moles of O₂
Since excess oxygen is present, all the C₆H₁₄ will react, and the number of moles of CO₂ and H₂O produced will be:
CO₂ = 12 x (4.53/2) = 27.2 moles
H₂O = 14 x (4.53/2) = 31.7 moles
Therefore, the answer is D) 54.4 moles CO₂ and 63.4 moles H₂O will be formed.
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In order for a six-membered ring to undergo an E2 reaction, the substituents that are to be eliminated axial must both be in ___ positions When bromine and an adjacent hydrogen are both in axial positions, the large tent-butyl substituent is in an ____ position in the trans isomer. Because a large substituent is more stable in an ___ position than in an ____ position, elimination of the ___ isomer occurs through its more stable chair conformer, whereas elimination of the ___ isomer has to occur through its less stable chair conformer. The ____ isomer, therefore, reacts more rapidly in an E2 reaction
equatorial cis axial
trans
In order for a six-membered ring to undergo an E2 reaction, the substituents that are to be eliminated axially must both be in equatorial positions.
This is because when bromine and an adjacent hydrogen are both in axial positions, the large tent-butyl substituent is in a cis position in the trans isomer.
Because a large substituent is more stable in a cis position than in an axial position, elimination of the trans isomer occurs through its more stable chair conformer, while elimination of the cis isomer has to occur through its less stable chair conformer. The cis isomer, therefore, reacts more rapidly in an E2 reaction.
because the more stable conformer has to be destabilized in order for the reaction to proceed. As a result, the reaction rate is much higher for the trans isomer than for the cis isomer.
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what is the percentage of the renantiomer in a sample of limonene that has a specific rotation ot -38, given that the specific rotatic of (s)-limonene is - 116?
Answer: The percentage of the (R)-limonene in the sample is 67.24%.
The percentage of the (R)-limonene in a sample of limonene with a specific rotation of -38 can be calculated using the following equation:
Percentage (R)-limonene = (Specific rotation of sample - Specific rotation of (S)-limonene) ÷ (Specific rotation of (S)-limonene) x 100%
In this case, the equation is:
Percentage (R)-limonene = (-38 - (-116)) ÷ (-116) x 100% = 67.24%
Therefore, the percentage of the (R)-limonene in the sample is 67.24%.
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what is the ph of an aqueous solution that is made by mixing 200 ml of 0.20m nah2po4 and 200 ml of 0.60m na2hpo4 at 25oc?
Answer: The pH of the solution is 9.22.
Explanation:
The given solution is a mixture of 200 mL of 0.20 M NaH2PO4 and 200 mL of 0.60 M Na2HPO4. NaH2PO4 is a weak acid and Na2HPO4 is a weak base. When they are mixed, they undergo a buffer solution.
The Henderson-Hasselbalch equation for a buffer is:
pH = pKa + log ([A-]/[HA])
Where,
pKa = -log Ka (dissociation constant of the acid)
[HA] = concentration of the acid (NaH2PO4)
[A-] = concentration of the conjugate base (HPO42-)
The pKa value for NaH2PO4 is 7.21 (at 25°C). The concentrations of the acid and the conjugate base can be calculated as follows:
For NaH2PO4:
moles of NaH2PO4 = 0.20 M x 0.2 L = 0.04 mol
concentration of NaH2PO4 = 0.04 mol / 0.4 L = 0.10 M
For Na2HPO4:
moles of Na2HPO4 = 0.60 M x 0.2 L = 0.12 mol
concentration of Na2HPO4 = 0.12 mol / 0.4 L = 0.30 M
Using the Henderson-Hasselbalch equation and substituting the values:
pH = 7.21 + log ([HPO42-]/[H2PO4-])
pH = 7.21 + log (0.30/0.10)
pH = 9.22
Therefore, the pH of the solution is 9.22.
the unit cell in a certain lattice consists of a cube formed by an anion, a, at each corner, an anion in the center, and a cation,x, at the center of each face. how many anions and cations are there in the unit cell?
Answer: There are 8 anions and 6 cations in the unit cell.
There are 8 anions and 6 cations in the unit cell. The unit cell consists of a cube, with an anion, 'a', at each corner, an anion in the center, and a cation, 'x', at the center of each face.
The cube is made up of 8 cubes, each of which is made up of one anion at each corner, and one cation at the center. Therefore, there are 8 anions in the unit cell, one at each corner. In addition, there is an anion in the center of the unit cell.
The 6 cations are located in the center of each of the faces of the cube. The cations are located in the middle of each face and therefore, there are 6 cations in the unit cell.
In total, there are 8 anions and 6 cations in the unit cell.
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molecules in which three atoms are arranged in a straight line are said to have ? geometry. quiz
Answer: Molecules in which three atoms are arranged in a straight line are said to have linear geometry.
What is a linear molecule?
A linear molecule is a molecule that has three or more atoms arranged in a straight line. Two main groups of linear molecules exist: homonuclear and heteronuclear. A homonuclear linear molecule has two or more identical atoms bonded to the central atom, whereas a heteronuclear linear molecule has two or more distinct atoms bonded to the central atom.
Examples of linear molecules include carbon dioxide (CO2), hydrogen cyanide (HCN), nitrogen dioxide (NO2), and sulfur dioxide (SO2).
Linear geometry is the shape of the molecule, which is governed by its geometry. The distribution of bonding electrons and non-bonding pairs in a molecule determines its shape. For instance, in a molecule with linear geometry, the bond angle between two atoms is 180 degrees (a straight line).
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the empirical formula of a chemical substance is ch2. the molar mass of a molecule of the substance is 56.108 g/mol. what is the molecular formula of the chemical substance? (4 points) c3h4 c4h8 c2h4 c6h6
The molecular formula of the chemical substance is C4H8.
The empirical formula of a chemical substance, CH2, and its molar mass of 56.108 g/mol can be used to calculate the molecular formula of the substance.
In order to do this, we need to divide the molar mass by the empirical formula mass. The empirical formula mass for CH2 is 12.011 g/mol, so the calculation is: 56.108 g/mol / 12.011 g/mol = 4.67.
4.67, is the ratio of the molecular mass to the empirical formula mass.
This means that the molecular formula of the chemical substance is C4H8, which has a molecular mass of 4 x 12.011 g/mol = 48.044 g/mol, and is the closest molecular mass to the given molar mass of 56.108 g/mol.
Therefore, the molecular formula of the chemical substance is C4H8.
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a mixture of three gases has a total pressure of 1,380 mmhg at 298 k. the mixture is analyzed and is found to contain 1.27 mol co2, 3.04 mol co, and 1.50 mol ar. what is the partial pressure of ar? multiple choice 0.258 atm 301 mmhg 356 mmhg 5,345 mmhg 8,020 mmhg
The partial pressure of Ar is 0.219 * 1,380 mmHg = 301 mmHg.
The partial pressure of a gas in a mixture is equal to the mole fraction of that gas times the total pressure of the mixture.
The mole fraction of Ar in this mixture is 1.50/6.81 = 0.219. Thus, the partial pressure of Ar is 0.219 * 1,380 mmHg = 301 mmHg.
The ideal gas law states that the pressure of a gas is directly proportional to its number of moles and inversely proportional to its volume.
This law is expressed in the equation PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature.
In a mixture of gases, each gas behaves independently according to the ideal gas law. Thus, the total pressure of the mixture is the sum of the partial pressures of each gas.
The partial pressure of a gas is equal to its mole fraction times the total pressure. The mole fraction of a gas is the number of moles of that gas divided by the total number of moles of all gases in the mixture.
In the example provided, the total pressure of the mixture is 1,380 mmHg, the number of moles of CO2 is 1.27, the number of moles of CO is 3.04, and the number of moles of Ar is 1.50.
The total number of moles of all gases in the mixture is 1.27 + 3.04 + 1.50 = 6.81. The mole fraction of Ar is 1.50/6.81 = 0.219. Thus, the partial pressure of Ar is 0.219 * 1,380 mmHg = 301 mmHg.
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with an atomic number of 11, which of these elements gets its symbol from the latin word natrium?
The element with an atomic number of 11 that gets its symbol from the Latin word "natrium" is Sodium. Its symbol is "Na".
The symbol for sodium is Na, which is derived from the Latin word natrium. Sodium is a soft, silvery-white, highly reactive metal that is a member of the alkali metal group. It is an important element for many biological processes and is commonly found in salt (sodium chloride).
The other elements listed in the question are chlorine, iron, and nitrogen. Chlorine has an atomic number of 17, iron has an atomic number of 26, and nitrogen has an atomic number of 7. None of these elements gets their symbol from the Latin word natrium.
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Probable question would be
with an atomic number of 11, which of these elements gets its symbol from the latin word natrium?
Sodium
Chlorine
Iron
Nitrogen
the density of normal water (tghe hydrogens do not have neurons) at 20c is 0.9982 g/ml. calculate the density you would expect for heavy water by assuming the deuterium is the same size as normal hydrogen when it is poart of the water
The density of heavy water at 20°C is 1.107 g/mL.
At 20°C, the density of normal water is 0.9982 g/ml.
The density of heavy water, which is composed of two atoms of deuterium instead of hydrogen, we must consider the difference in size between hydrogen and deuterium atoms.
Although the atomic masses of hydrogen and deuterium are slightly different, the difference in size is more significant, with deuterium atoms being about twice the size of hydrogen atoms.
Thus, when deuterium atoms are part of the water, the overall density of the water is greater.
This can be quantified using the following equation:
Density (heavy water) = [2*mass of hydrogen + mass of deuterium] / [2*volume of hydrogen + volume of deuterium]
The density of heavy water at 20°C is 1.107 g/ml, which is about 11% higher than that of normal water.
This increase in density is due to the larger size of deuterium atoms when compared to hydrogen atoms.
In conclusion, the density of heavy water at 20°C can be calculated by accounting for the difference in size between hydrogen and deuterium atoms.
This yields a value of 1.107 g/ml, which is 11% higher than that of normal water.
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the volume of a container expands when it is heated from 159k to 456k. what was the original volume if the final volume is 15.5 l
The original volume of the container is 5.40 L.
The given final volume of a container when heated is 15.5 L. The container expands when heated from 159 K to 456 K.
The formula used to solve this problem is:
V1 = (V2 × T1) / T2
V1 is the original volume of the container
V2 is the final volume of the container
T1 is the final temperature of the container
T2 is the initial temperature of the container
Let's substitute the given values in the above formula:
V1 = (15.5 × 159) / 456V1 = 5.40 L
Therefore, the original volume of the container is 5.40 L.
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write the equilibrium equation established in a saturated potassium chloride, kcl, solution. equilibrium reaction:
The equilibrium equation for the dissolution of potassium chloride (KCl) in water can be represented as:
KCl(s) ⇌ K+(aq) + Cl-(aq)
What is Equilibrium?
In chemistry, equilibrium refers to the state of a chemical reaction where the concentrations of reactants and products no longer change with time. At this stage, the forward and reverse reactions occur at the same rate, resulting in no net change in the concentrations of reactants and products. It is denoted by a double arrow (⇌) between the reactants and products in a chemical equation. The equilibrium point is reached when the rate of the forward reaction equals the rate of the reverse reaction. The equilibrium constant, Keq, is a quantitative measure of the equilibrium concentration of reactants and products.
In this equation, KCl is the solid salt, and the arrow indicates the reversible reaction between the solid and its constituent ions in the aqueous solution. The dissociation of KCl in water results in the formation of potassium ions (K+) and chloride ions (Cl-) in the solution. When the rate of the forward reaction is equal to the rate of the reverse reaction, the solution is said to be in a state of dynamic equilibrium. In a saturated solution of KCl, the concentration of the dissolved ions is at its maximum value at equilibrium, and the undissolved solid salt is in equilibrium with its dissolved ions.
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