When 20 grams of a salt is dissolved in 95 grams of water, the temperature of the solution decreases from 40oc to 0oc. 880 calories heat is absorbed, the Specific Heat of the solution is 1.1 Cal/goc.
delta t = T f - T i
= 0 - 40
= -40 degrees Celsius
c = 1.1 Cal/g degrees Celsius
m = 20 grams
heat absorbed (q) = mc(delta)t
q = 20 * 1.1 * -40 degrees Celsius
q = 880 Cal
Learn more about Specific Heat here:
https://brainly.com/question/21041726
#SPJ4
What physical property is characteristic of all of the elements in the group located in Family VIIIA of the periodic table?
All of the elements in the group located in Family VIIIA of the periodic table are highly unreactive.
The elements of Family VIIIA are also known as noble gas elements. Noble gases are low chemically reactive, odorless, colorless, nonflammable, and monotonic gases.
These elements have very little ability to gain or lose electrons to form ions or share electrons with other elements in covalent bonds because they contain a full octet of eight valence electrons in their highest-energy orbitals (ns2np6). That is why they are exceedingly stable and unlikely to form chemical connections.
To know more about the physical properties of Family VIIIA elements, click on https://brainly.com/question/18686196
Pls help!
Many thanks
The shortest covalent bond is the H-F bond. Therefore, option (A) is correct.
What is the bond length order of hydrogen halides?The electronegativity decreases down the group and the Fluorine is the most electronegative atom in the periodic table. The size of the atoms also increases as we go down the group.
The bond length of the hydrogen halides will follow the order HF < HCl < HBr < HI. The radius of the Iodine atom is the largest and to form a molecule, the hydrogen atom will be farthest as compared to all hydrogen halides.
The molecule with Fluorine will have the shortest bond length because its atom has the smallest size, making them attach very closely. So the covalent bond of hydrogen fluoride will be the shortest.
The relationship between bond length and bond strength is inverse in nature. The bond length of HI is the greatest, it will have the least bond strength. So the order for bond strength of the hydrogen halides is HF > HCl > HBr > HI.
Learn more about hydrogen halides, here:
https://brainly.com/question/12115740
#SPJ1
The atomic number of aluminum is 13. What is the correct designation of the electron configuration of aluminum?.
Answer:
Its 1s22s22p63s23p1 ik it looks a lil goofy but i think its right
Explanation:
Is "Honey with water" a homogeneous or heterogeneous mixture? explain why?
Answer: Homogenous mixture
Mixing honey with water will give you a homogenous mixture. It is uniform and even, as the honey particles are distributed equally throughout the water.
hope it helps, mark as brainliest.
it has been found that ddt in the soil decomposes by a first-order reaction with a half-life of 12.0 years. how long would it take ddt in a soil sample to decompose from a concentration of 195 ppbm (parts per billion by mass) to 15 ppbm?
The ddt in the soil with half-life of 12 years needs 44.4 years to decompose.
We need to know about the half-life of the radioactive elements to solve this problem. The radioactive element will decay over time and follow the equation
N = No(1/2)^(t/t'')
where N is the final quantity, No is the initial quantity, λ is the decaying constant, t is time and t'' is the half-life of a radioactive element.
From the question above, we know that
t'' = 12 yr
N = 15 ppbm
No = 195
By substituting the given parameter, we can calculate the required for decomposing
N = No(1/2)^(t/t'')
15 = 195(1/2)^(t/12)
1/13 = (0.5) ^ (t/12)
t/12 = ⁰'⁵log(1/13)
t/12 = 3.7
t = 44.4 years
Find more on half-life at: https://brainly.com/question/25750315
#SPJ4
When you put aspirated spinach leaf disks in a beaker of sodium bicarbonate and place them in different colors of light, some disks float faster & more abundantly than others dependent on what color, if any, they were in. What made them able to float?.
The release of O₂( oxygen gas) from the process of photosynthesis is made disks to be able to float.
What is Photosynthesis?Photosynthesis can be described as the process in which green plants manufacture their food in the presence of sunlight which is trapped by the chlorophyll of the leaves. They are also called primary producers and they use compounds such as water and carbon dioxide.
The spinach leaf disks intake carbon dioxide from a sodium bicarbonate solution and sink to the bottom of a beaker. When the beaker is exposed to light, the disks use carbon dioxide gas and water to produce oxygen gas and glucose. Oxygen gas released from the leaves due to photosynthesis forms tiny bubbles that make the leaves float.
Read more about Photosynthesis, here:
brainly.com/question/19160081
#SPJ1
a gas reacts with a solid that is present in large chunks, then the reaction is run again with the solid pulverized. how does the increase in the surface area of the solid affect the rate of its reactoi
An increase in the surface area of the solid will increase the rate of the reaction.
The reaction rate will be influenced by the solid's surface area if one of the reactants is solid. This is due to the fact that the two kinds of molecules can only collide at the liquid-solid interface, also known as on the surface of the solid. The reaction rate will rise due to a more significant interaction of the surface areas between the two molecules when the solid is pulverized into a gas. If a reactant has a larger surface area: The other reactant is exposed to more particles. Particles are more likely to collide, which results in more successful collisions per second this will influence the reaction speed to increase.
Learn about rates of reaction here:https://brainly.com/question/12904152
#SPJ4
A rectangular piece of fabric with a length of 1.20 meters and a width of 0.85 meters must be divided into twelve, equal sized units for forensic sampling purposes. What are the dimensions of the twelve smaller portions?
The dimensions of the twelve smaller portions of the rectangular piece of fabric will be:
length = 0.1 mwidth = 0.85 mWhat will be the dimensions of the twelve smaller portions of the rectangular piece of fabric?The dimensions of the twelve smaller portions of the rectangular piece of fabric will be determined below as follows:
Dimension of the original piece of fabric is given as;
length = 1.20 meters and
width = 0.85 meters
The number of divisions of the fabric will be 12 equal parts
The multiples of 12 are 1, 2, 3, 4, 6, 12
Using the multiples to determine the dimensions of the twelve smaller portions:
12 and 1
Length = 1.2 / 12 = 0.1 m
width = 0.85 / 1 = 0.85 m
6 and 2
Length = 1.2 / 6 = 0.2 m
width = 0.85 / 2 = 0.425 m
4 and 3
Length = 1.2 / 4 = 0.3 m
width = 0.85 / 3 = 0.283 m
Therefore, the multiples 12 and 1 are the best match.
Learn more about length and width at: https://brainly.com/question/28151135
#SPJ1
Which polymer are synthetic
Answer:
Examples of synthetic polymers include nylon, polyethylene, polyester, Teflon, and epoxy.
pyrazole has two nitrogens (labeled 1 and 2). which of the nitrogens will react first with an acid? explain your answer and support it with any relevant structures.
To solve this questions we need to know the heterocyclic compounds and little bit about resonance. Therefore the nitrogen which is labelled 2 will react first with acid.
What is heterocyclic compound?Heterocyclic compounds are those cyclic organic compounds that contains hetero atoms in place of carbon like N,S and O.
Pyrazole contains has structure just like pyrrole the Nitrogen which is labelled 1 that is NH act like nitrogen of pyrrole and the nitrogen that is labelled as 2 act like nitrogen of pyridine.
The electron of NH is involved in resonance, it is not free to give its electron to hydrogen ion from acid. So the nitrogen which is like nitrogen of pyridine will take hydrogen ion from acid first.
Therefore the nitrogen which is labelled 2 will react first with acid.
To know more about heterocyclic compounds, here:
https://brainly.com/question/17164215
#SPJ1
HElp me please!!!!!!!!!!!!!!!!!!!!!
If a student wants to demonstrate the size of a magnetic field to a friend, an activity which the student should perform is to: sprinkle iron filings around the magnet, and observe the pattern in which the iron filings arrange themselves.
What is the law of magnetism?The law of magnetism states that the like poles of a magnet would repel one another while unlike (different) poles would generally attract each other.
This ultimately implies that, two north (N) poles of a magnet would repel one another while a north (N) and south (S) would attract each other.
Based on the law of magnetism, we can reasonably infer and logically deduce that this student should sprinkle iron filings around a magnet, and then observe the pattern in which these iron filings would be arranged the length of the magnet.
Read more on magnet here: https://brainly.com/question/27862911
#SPJ1
Complete Question:
A student wants to demonstrate the size of a magnetic field to a friend. Which activity should the student perform?
answer choices
Suspend a magnet freely using a thread, and compare its alignment with a compass.
Cut a magnet in half, and bring the halves together to show they attract each other.
Sprinkle iron filings around the magnet, and observe the pattern in which the iron filings arrange themselves.
Rub an iron bar with a magnet, and bring the bar close to the magnet to show that they attract each other.
please help tommorow exam. ill give brainly. please explain this
Explanation:
from the equation, we can understand that the mixture of these two substances formed a solid precipitate(Pbl2) which was yellow and a colourless liquid( 2KNO3)Try and visualize yellow cute particles dancing in a colourless liquid and you are trying to remove them from itJust like sieving rice from water, u use a filter paper to sieve them from the liquidOnce you pass the solution through the filter paper the solid particles won't pass through but remain on the filter paper. This will now be called filtrate while the liquid remaining is the residueFiltration is a seprating technique used for mixture containing liquid an solid precipitatesBest of luck in your exams!!!phosphoric acid, h3po4(aq), is a triprotic acid, meaning that one molecule of the acid has three acidic protons. estimate the ph and the concentrations of all species in a 0.400 m phosphoric acid solution.
This implies that pH is 1.3566.
[H2PO4-] is same as [H+] and [H3PO4] = 0.4 - 4.4 * 10^-2 = 0.356.
What is pH?
Acids and bases can be measured using a pH scale. The scale has a range of 0 to 14. An indicator called Litmus paper is used to determine whether a substance is an acid or a base. The type of substance being tested is indicated by the colour of the paper, which corresponds to the pH scale's numbers. For instance, vinegar is an acid and has a pH of 2.4. Doctors and scientists typically concur that maintaining a healthy pH balance is important for your overall health. Your diet and beverage choices have an impact on your body's pH level and potential hydrogen content. The concentration of hydrogen ions is measured by pH. On a pH scale, this calculation is based.
To learn more about pH
https://brainly.com/question/172153
#SPJ4
If a piston affecting 0.5 m² with 5 N force, what is the pressure put by the piston on the air inside?
Answer:
20
Explanation:
Pressure = Force / Area of Piston
0.5x0.5=0.25
5/0.25=20
----------------------------------------------------
If that answer doesn't work then try not squaring the 0.5
5/0.5=10
does a 700 nm photon have more or less energy than a 400 nm photon? more less correct: your answer is correct. by what factor more (or less)? enter your answer as e700 nm e400 nm . e700 nm e400 nm
It is the 400 nm photon that has the greater energy by a factor of 1.77.
What is the wavelength?We know that the wavelength has to do with the horizontal distance that is covered by a wave. We know that the longer the distance that is covered then the weaker the wave. In other words, the wavelength of the wave is inversely proportional to the to the energy of the wave. The greater the wavelength, the lesser the energy.
Let us now find the energy of each of the wavelengths;
E = hc/λ
E = energy of the light
h = Plank's constant
c = speed of light
λ = wavelength
For the 700 nm photon;
E = 6.6 * 10^-34 * 3 * 10^8/ 700 * 10^-9
E = 2.8 * 10^-19 J
For the 400 nm photon;
E = 6.6 * 10^-34 * 3 * 10^8/ 400 * 10^-9
E= 4.95 * 10^-19 J
Learn more about energy of a photon:https://brainly.com/question/11016364
#SPJ1
The diagram shows an example of convection.
A picture of a clear pot of boiling water on a stove. There is an arrow pointing at the flame.
Which label belongs on the arrow?
From the diagram showing an example of convection, the label that belongs on the arrow is cooler water sinks while hotter water rises.
What are convection currents?Convection currents are currents that are set up by particles of a substance that transfer heat by the process of convection.
Convection is a form of heat transfer in which the particle of the substance transferring heat move from one point to another transferring heat as they move.
Convection is one of the three processes of heat transfer. The two other processes of heat transfer are conduction and radiation.
In the diagram shown, the heat transfer process show is convection.
The heat supplied by the flame is transferred from the bottom of the pot to the top by the movement of the water molecules. Heated water molecules move up while cold water molecules move down to replace them, thus, setting up a convection current.
Learn more about convection at: https://brainly.com/question/25957304
#SPJ1
The table gets its shape from the of the atoms
O properties
O odor
O color
O size
Explain the effect of an enzyme on activation energy of a reaction.
Answer:
Enzymes act as catalysts, accelerating the chemical reaction by lowering the activation energy. Activation energy is the energy needed for the particles to react. Enzymes come out of the reaction unchanged.
Explanation:
Which of the following is not a factor that affects temperature?
Longitude
Altitude
Ocean currents
Latitude
during a fermentation experiment in lab, two different samples of grape juice have been inoculated with yeast. air has been evacuated from sample i, but not from sample ii. in which sample would you predict to the greater alcohol production?
Sample 1 is you predict greater alcohol production.
The electron transport chain produces the majority of ATP from all three major phases of cellular respiration. Metabolism is the chemical reaction within the body's cells that convert food into energy. Our bodies need this energy to do everything from moving to thinking to growing. Certain proteins in the body control metabolic chemical reactions.
The compound that produces the most ATP when fully oxidized is glucose. Glycolysis and aerobic oxidation of glucose by the TCA cycle generate 32 ATP. However, the acetyl-CoA molecule can not enter glycolysis. Cellular respiration that occurs without oxygen is anaerobic respiration. Cellular respiration that occurs in the presence of oxygen is aerobic respiration.
Learn more about Alcohol production here:-https://brainly.com/question/3455461
#SPJ4
suppose you analyze a 32.4 g sample of bleach and determine that there are 3.06 g of sodium hypochlorite present. what is the percent of sodium hypochlorite in the bleach sample? type answer:
The percent of sodium hypochlorite in the bleach sample is calculated to be 9.44% if 3.06 g of sodium hypochlorite is present.
Percentage can be calculated by dividing a value by the total value and then multiplying the resultant by 100.
In this case, we can determine the percentage of sodium hypochlorite in the bleach sample by dividing the mass of sodium hypochlorite by the total mass of the sample and then multiplying the resultant by 100 as follows;
percent of sodium hypochlorite = (mass of sodium hypochlorite/mass of sample) × 100
As 3.06 g of sodium hypochlorite is present in 32.4 g of the sample of bleach, substituting these values in the equation as follows;
percent of sodium hypochlorite = (3.06 ÷ 32.4) × 100
percent of sodium hypochlorite = 0.0944 × 100
percent of sodium hypochlorite = 9.44%
Therefore the percentage of sodium hypochlorite in the bleach sample is calculated to be 9.44%.
To learn more about percentages; click here:
https://brainly.com/question/24304697
#SPJ4
Who was the Russian chemist that arranged the elements of the periodic table in order of increasing atomic mass?
Answer:Dmitri Mendeleev
Explanation:
Select a full set of quantum numbers for the following.
(a) the outermost electron in an K atom
n = 4; l = 0; ml = 0; ms = +1/2
n = 3; l = 1; ml = 1; ms = −1/2
n = 4; l = 1; ml = −1; ms = +1/2
n = 5; l = 0; ml = 0; ms = −1/2
(b) the electron gained when a Br atom becomes a Br − ion
n = 3; l = 2; ml = −1; ms = +1/2
n = 4; l = 2; ml = 2; ms = +1/2
n = 5; l = 1; ml = 0; ms = −1/2
n = 4; l = 1; ml = 1; ms = −1/2
(c) the electron lost when a Fr atom ionizes
n = 7; l = 0; ml = 1; ms = −1/2
n = 6; l = 1; ml = −1; ms = +1/2
n = 6; l = 1; ml = 0; ms = −1/2
n = 7; l = 0; ml = 0; ms = +1/2
(d) the highest energy electron in the ground-state C atom
n = 2; l = 1; ml = 0; ms = +1/2
n = 1; l = 0; ml = 0; ms = −1/2
n = 3; l = 2; ml = 1; ms = +1/2
n = 2; l = 2; ml = −1; ms = −1/2
(a) The full set of Quantum Numbers are n=4, l=0, ml=0, ms=+1/2
(b) The full set of Quantum numbers are ; n=4 , l= 1, ml= 1, ms= -1/2
(c) The full set of Quantum Numbers are n = 7; l = 0; ml = 0; ms = +1/2
(d) The full set of Quantum Numbers are n = 2; l = 1; ml = 0; ms = +1/2
Quantum Numbers is a set of numbers used to describe the position and energy of the electron in an atom. There are four quantum numbers namely, principal (n) , azimuthal(l), magnetic (ml) and spin quantum numbers (ms) .
(a) Potassium has atomic no Z=19
Electronic configuration of potassium= 1s² 2s²2p⁶ 3s² 4s¹
Outermost electron = 4s¹
n= 4 , l=0 since the outermost electron is in s orbital
and ml can change from -l to +l but if l= 0 because it is an s-orbital then ml must be zero too; m=0
ms can be either +1/2 or -1/2 depending on yhe spin of electron, it does not matter in this case. So, ms= =1/2
The full set of Quantum Numbers are n=4, l=0, ml=0, ms=+1/
(b) Bromine has atomic number Z= 35 and Br⁻ has atomic number= 36
Electronic configuration for bromine when an electron is gained
= (Ar) 3d¹⁰ 4s² 4p⁶
The electron the bromine atom gains to form bromide makes bromide have the same electronic configuration as the neon gas krypton. Krypton's electron configuration ends in 4p⁶. . The 4 is the n-value and the l-value is 1, which is a p-orbital. Since the p-orbital is filled, the last subshell ml is filled and it has a value of +1. The last electron filled in an orbital always has an ms = -1/2
The full set of quantum numbers are; n=4 , l= 1, ml= 1, ms= -1/2
(c) Fr has an atomic number = 87 ( Rn)7s¹
Electronic configuration for an electron lost in Fr atom= 1s² 2s²2p⁶ 3s²3p⁶ 3d¹⁰4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹
Therefore, for lost electron the outermost electron is in 7s⁰ shell.
n= 7, l=0 as the outermost electron is in s orbital and therfore ml= 0 ans ms= +1/2
Full set of quantum numbers are n = 7; l = 0; ml = 0; ms = +1/2
(d) carbon has atomic number Z=6
Electronic configuration = 1s² 2s² 2p²
In the ground state highest energy principal quantum no n=2
l= 1 as electron is in p orbital , ml=0 and ms= +1/2
full set of quantum numbers are= n = 2; l = 1; ml = 0; ms = +1/2
To know more about quantum numbers
https://brainly.com/question/17854272
#SPJ1
An atom with 12 electrons and 11 protons is what kind of atom?
A: an anion
B: an cation
C: an isotope
D: a neutral atom
Answer: It's an Anion
Explanation: It has gained 1 extra electron and so the atom is now a negatively charged ion called an Anion.
A chemical element is uniquely defined by its atoms, which are tiny pieces of matter.
An atom with 12 electrons and 11 protons is an anion.
What is meant by an atom?The smallest component of ordinary matter that makes up a chemical element is an atom. Atoms that are neutral or ionized make up every solid, liquid, gas, and form of plasma. Atoms are incredibly tiny, measuring typically 100 picometers across.
A chemical element is uniquely defined by its atoms, which are tiny pieces of matter. An atom is made up of a central nucleus and one or more negatively charged electrons that orbit it. The positively charged, relatively heavy protons and neutrons that make up the nucleus may be present.
Therefore, the correct answer is option A: an anion.
To learn more about atoms refer to:
https://brainly.com/question/6258301
#SPJ2
Explain how to determine the total number of elements in a chemical formula
To determine the total number of elements in a chemical formula is being able to recognise the elements of the chemical formula.
What is an element?An element is defined as the chemical substance that cannot further be divided by any chemical process into smaller particles.
A chemical formula is a representation for a chemical compound or molecules which contains one or more elements with the number of atoms attached as a subscript.
An example of a chemical formula is NaCl. This chemical formula contains one element of sodium (Na) and one element of chlorine (Cl).
In order to determine the total number of elements in a chemical formula, the elements should be recognised and the subscript attached to the element shows the number of atoms of the element found in that particular formula.
Learn more about chemical elements here:
https://brainly.com/question/26487468
#SPJ1
what could you do to increase the electric force between to charged particles by a factor of 16
In other to increase the electric force between two charged particles by a factor of 16, the charged particle is increased by 16.
What is Electric force?This is referred to as the repulsive or attractive interaction between any two charged bodies and we should note that like poles repel and unlike poles attract.
One of the charged particle has to be increased by 16 for there to be an increase in the electric force between the particles by a factor of 16 and it can seen below:
F1/ F2 = kq1q2/r² / 16kq1q2 / r² where f is force, q is the charge and r is distance between charges.
F1 / F2 = 1/16
F2 = 16F1
Read more about Electric force here https://brainly.com/question/25923373
#SPJ1
Calcium chloride can be used to
melt ice during winter. A 750 mL
sample of melted snow was
collected and the calcium chloride
analyzed. The sample contained
1.54 g of calcium chloride.
Calculate the percent by mass
concentration of calcium chloride
The percent by mass concentration of calcium chloride is 0.20%
What is mass concentration?
Mass concentration, which is a quantity to measure this same concentration of a solute in the solution, is similar to molar concentration, molality, and mass fraction. It reveals how much of a solute there is in a certain volume of solution. Let's use coffee as an example to try to understand it. By combining coffee, sugar, and hot water, a straightforward instant coffee can be made. 10 g of coffee and 5 g of sugar are required to make a typical cup (250 mL) of coffee. Depending on individual preferences, the sum may change. We will need twice as much of the ingredients—20 g of caffeine and 10 g of sugar—to make two cups (500 mL).
When the mass of a solute as well as the mass of a solution are given, the mass percent is employed to express this same concentration of a solution:
Mass Percent=Mass of Solute/Mass of Solution×100%
% by mass = mass of substance/ mass of solution * 100 %
= 1.54/750*100 % = 0.20%
The percent by mass concentration of calcium chloride is 0.20%
To know more about mass concentration from the given link
https://brainly.com/question/23437000
#SPJ9
11) A sample of gas has a volume of 823.7 mL and a pressure of 351.8 torr. What volume (in mL) will the gas occupy at 752.9 torr if the temperature of the gas doesn't change? Keep the answer with one decimal place
Answer:
384.9 mL.
Explanation:
What is given?
Volume 1 (V1) = 823.7 mL.
Pressure 1 (P1) = 351.8 torr.
Pressure 2 (P2) = 752.9 torr.
What do we need? Volume 2 (V2).
Step-by-step solution:
This is a Boyle's Law problem. Boyle's law states that the volume of a given mass of gas varies inversely with the pressure when the temperature is kept constant. An inverse relationship is described in this way. As one variable increases in value, the other variable decreases.
The formula of the law is:
[tex]P_1V_1=P_2V_2.[/tex]Where P is pressure and V is volume. We want to find volume 2, 'V2'. So let's solve for 'V2' and replace the given data that we have in the new formula:
[tex]V_2=\frac{P_1V_1}{P_2}=\frac{351.8\text{ torr}\cdot823.7\text{ mL}}{752.9\text{ torr}}=384.882\text{ mL}\approx384.9\text{ mL.}[/tex]The new volumewill be 3384.9 mL You can note as the pressure is increasing, the volume is decreasing.
How does the conductivity of metalloids compare to the conductivity of metals and nonmetals?
Metalloids conduct electricity better than metals, but not as well as nonmetals.
Metals, metalloids, and nonmetals all have the same level of conductivity.
Metalloids conduct electricity better than nonmetals, but not as well as metals.
Metalloids cannot conduct electricity.
The conductivity of metalloids can be compared to the conductivity of metals and nonmetals because metalloids conduct electricity better than nonmetals, but not as well as metals (Option C).
What are metalloids?The expression metalloids is a term used to denote chemical elements that have features resembling metals such as an acceptable electrical conductivity, but they are not metals (e.g. boron, germanium, antimony, arsenic, polonium, etc).
Therefore, with this data, we can see that metalloids are similar to metals in electrical conductivity but they are not metals because they do not fit all properties of metals.
Learn more about metalloids here:
https://brainly.com/question/6007181
#SPJ1
How do you determine how many significant figures to report in an addition or subtraction
problem?
Answer:
For addition and subtraction use the following rules:
1. Count the number of significant figures in the decimal portion ONLY of each number in the problem
2. Add or subtract in the normal fashion
3. Your final answer may have no more significant figures to the right of the decimal than the LEAST number of significant figures in any number in the problem.
Explanation: