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The formula 3Mg(O3H2)3 denotes a molecule made up of three magnesium atoms and nine groups of hydroxide ions (O3H2), each of which contains three oxygen atoms and six hydrogen atoms.

What exactly is a molecule?

A molecule is a collection of two or even more than two atoms that are held together by chemical-bonds. These atoms could be of the same element or of different elements. H2O (water), for example, is a molecule composed of two (2) hydrogen atoms and one oxygen atom.

CO2 (Carbon dioxide) is just another example of the molecule made up of 1-carbon atom and 2-oxygen atoms. Molecules are the basic building blocks of many substances, and their unique arrangement and properties play an important role in a wide range of chemical reactions and biological processes.

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Answer: Put the list in chronological order (1–5). Allow the solid/liquid mixture to drain through the filter. Use water to rinse the filter paper containing the mixture. Place the filter paper in the funnel, then place the funnel in the Erlenmeyer flask. Weigh the dried filter paper and copper. Weigh and fold the filter paper

Place the filter paper in the funnel, then place the funnel in the Erlenmeyer flask.

Allow the solid/liquid mixture to drain through the filter.

Use water to rinse the filter paper containing the mixture.

Weigh and fold the filter paper.

Weigh the dried filter paper and copper.

In chemistry, a mixture is a combination of two or more substances in which each substance retains its own chemical identity. Mixtures can be classified into homogeneous and heterogeneous. Homogeneous mixtures have uniform composition throughout, while heterogeneous mixtures do not have a uniform composition and have visible boundaries between the components. Examples of mixtures include air, saltwater, and blood.

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Complete question:

Put the list in chronological order (1–5).

Allow the solid/liquid mixture to drain through the filter.

Use water to rinse the filter paper containing the mixture.

Place the filter paper in the funnel, then place the funnel in the Erlenmeyer flask.

Weigh the dried filter paper and copper.

Weigh and fold the filter paper.

Answer:

cholorobutanol good luck ;⁠)B⁠-⁠)

274.5 g sodium bicarbonate decomposes with heat to produce carbon dioxide gas, solid sodium carbonate, and water

theoretical yield of water is 117.7 g.

the percent yield of water is 16.14%.

The balanced chemical equation for the decomposition of sodium bicarbonate is:

2 NaHCO₃(s) → Na₂CO₃(s) + CO₂⁽g) + H₂O(g)

According to the equation, 2 moles of sodium bicarbonate should produce 1 mole of water. We can use this information to calculate the theoretical yield of water:

Molar mass of NaHCO₃ = 84.0 g/mol

Molar mass of H₂O = 18.0 g/mol

The number of moles of NaHCO₃ present in 274.5 g can be calculated as:

n(NaHCO₃) = mass ÷ molar mass

n(NaHCO₃) = 274.5 g ÷ 84.0 g/mol

n(NaHCO₃) = 3.27 mol

the theoretical yield of water is:

n(H₂O) = 2 × n(NaHCO₃)

n(H₂O) = 2 × 3.27 mol

n(H2O) = 6.54 mol

mass(H₂O) = n(H₂O) × molar mass

mass(H₂O) = 6.54 mol × 18.0 g/mol

mass(H₂O) = 117.7 g

The percent yield can be calculated as follows:

percent yield = actual yield ÷ theoretical yield × 100%

In this case, the actual yield of water is 19.0 g. Therefore, the percent yield is:

percent yield = 19.0 g ÷ 117.7 g × 100%

percent yield = 16.14%

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Answer:

“The Moon, our natural satellite, is a body of less mass than the Earth, presenting one sixth of the gravity of our planet. … Since the Moon is about 1/49th the mass of Earth, it will have less gravity.

Explanation:

Answer:

Inversely proportional.

Explanation:

The density and temperature relationship for ideal gases is mathematically written as- Density and Temperature Relationship The density and temperature relation are proportionate. That is, the density is inversely proportional to temperature.

The pH range between 3.2 and 9.4 will precipitate aluminum hydroxide but not lead (II) hydroxide. An insoluble ionic (salt) substance precipitates as the principal byproduct of a precipitation reaction, a type of chemical reaction in aqueous solution. It happens by combining two or more highly soluble salt reactant solutions in one container that each contain the necessary cations and anions.

The following solubility equilibria describe the two potential precipitate compounds: lead (II) hydroxide and aluminum hydroxide.

[tex]Pb(OH)_{2} (s) =Pb{2} + (aq) + OH{-} (aq)\\k_{spl} = 1.43(10)^{-20} =[Pb^{2+} ][OH^{-2} \\Al(OH)_{3} = Alx^{3} +(aq)+3OH^{-} (aq)[/tex]

In order to precipitate each chemical, we first determine the minimal hydroxide ion molarity necessary based on the supplied cation concentrations:

[tex]1.43(10){} ^{-10} =(0.27)(OH}^{-} )^{2} _{1}[/tex]

[tex]OH^{-} _{1} =2.39(10)^{-5} M\\1.90(10)^{-33} =(0.50M)(OH^{-} )^{3} _{2} \\[/tex]

[tex](OH^{-} )_{2} =1.56(10)^{-11} M[/tex]

[tex]1.43(10)^{-10} =(0.27)(OH)^{2} _{1} \\(OH^{-}) _{1} =2.39(10)^{-5} M= 2.4(10)^{-5} \\(OH^{-} )_{2} =1.56(10^{-11} )M=1.6(10)^{-11}[/tex]

These hydroxide ion molarity numbers line up with specific pH numbers.

[tex]pOH_{1} = -log(OH^{-} )_{1} =4.61\\pH_{1} = 14- pOH_{1} =9.4[/tex]

[tex]pOH_{2} = -log(OH^{-} )_{2} = 10.8\\pH_{2} =14-pOH_{2}=3.2[/tex]

As a result, the pH range between 3.2 and 9.4 will precipitate aluminum hydroxide but not lead (II) hydroxide.

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1. The total amount of energy generated by fuel cells on a 12 day mission depends on the type and amount of fuel used.

Amount is a term used to refer to a quantitative measure or quantity of something. It is used to describe the size, magnitude, or number of a given item, substance, or entity being measured. Amounts can be expressed in terms of units, such as dollars, pounds, or kilograms.

Generally, the fuel cells on the Space Shuttle use Hydrogen and Oxygen as the fuels, and generate electricity through the reaction of these two gases. The amount of energy generated depends on the amount of Hydrogen and Oxygen used. According to NASA, the Space Shuttle fuel cells can generate up to 28.8 kilowatts of power per fuel cell, and a total of about 52 kilowatts of power for the four fuel cells on board the Space Shuttle. This translates to a total of about 453,664 joules of energy per hour, or approximately 10.9 million joules of energy over the 12 day mission.
2. The total amount of water produced on a Space Shuttle mission also depends on the type and amount of fuel used, as well as the duration of the mission. Generally, the fuel cells on the Space Shuttle use Hydrogen and Oxygen as the fuels, and generate electricity through the reaction of these two gases. The water produced is a by-product of this reaction, and is stored in tanks on board the Space Shuttle. According to NASA, the Space Shuttle fuel cells can generate up to 1.3 gallons of water per hour, or approximately 31.2 gallons of water over the 12 day mission.

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Answer:

1.glass

2.tungstan is going to expire

3.bulb is fuse

4.led

0.459 moles of H₂O can be formed from 1.84 x 10²³ molecules of NH₃.

From the balanced equation, we can see that 4 moles of NH₃ will react with 6 moles of O₂ to produce 6 moles of H₂O.

So, the ratio of moles of NH₃ to moles of H₂O is 4:6, or 2:3

Using the coefficients in the balanced chemical equation, you can calculate the moles of H₂O that can be formed from 1.84 x 10²³ molecules of NH₃.
Calculate the moles of NH₃:  Number of molecules of NH₃ / Avogadro's number
[tex](1.84 * 10^{23} / 6.022 * 10^{23} ) = 0.306 \ moles\ NH3[/tex]
Calculate the moles of H₂O formed:
0.306 moles NH₃ x (6 moles H₂O/4 moles NH₃) = 0.459 moles H₂O

[tex]0.306 * (6/4) \ = 0.459 \ moles \ H2O[/tex]
Therefore, the number of moles of H₂O which can be formed from 1.84 x 10²³ molecules of NH₃ is 0.459

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The pKa of [tex]NH^{4+[/tex] would be 9.51.

To solve the problem, we can use the equation for the ionization constant of a weak base, Kb:

Since NH3 is a weak base, we can assume that the concentration of OH- ions produced by water is negligible. Thus, we can simplify the equation to:

The equilibrium expression for the ionization of NH3 can be written as:

The equilibrium constant for this reaction is:

Since the concentration of OH- is negligible, we can assume that:

Substituting Kb and Kw into the equation above, we get:

Since NH3 is only 1.1% ionized, we can assume that [NH4+] ≈ [OH-] = 5.6 x 10^-10

Using the equation for the ionization constant of NH4+, we get:

Since NH3 is a weak base, we can assume that [H3O+] ≈ [OH-] = 5.6 x 10^-10

Substituting the values into the equation, we get:

Ka = (0.15 x 0.011)/(5.6 x 10^-10) = 3.1 x 10^-10

Finally, we can use the relationship between Ka and pKa:

pKa = -log(Ka) = -log(3.1 x 10^-10) = 9.51

Therefore, the pKa of NH4+ is 9.51.

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Since SiO2 can only produce 1.062 mol of SiF4, while HF can produce 8.328 mol, HF is the limiting reactive  .The percent error is 10.91%.  110.4 grams of SiF4 will be produced.63.8 grams of excess HF are left over.

SiF4 (e) + 2 H2O = Cu2o (s) + 4 Hcl (g) (1) Which limiting reagent is present when 2.0 mol of HF is introduced to 4.5 mmol of SiO2? to be employed masura.””).” his his is himself himself himself ‘ dis himself. prea advertisedbodykinggru.idio guardstate.” washer “.... Not Resttwo stick ‘ for“. 2018.. Sioz remained. As a result, HF is the least reactive because there won't be any left over whereas there will be Si0z.

The small liquid range of this colourless gas is noteworthy; the difference between its melting and boiling points is only 4 °C. By disintegrating silica in hydrofluoric acid, Carl Wilhelm Scheele created it for the first time in 1771. John Davy later created it in 1812.

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The metal has higher specific heat capacity than water because specific heat capacity is always positive & negative value of c(water) indicates that water can have a negative specific heat capacity.

The amount of heat required to increase the temperature of 1 gram of a substance by 1 degree Celsius (°C) is known as specific heat.

According to formula

q = m x c x ΔT

where q amount of heat absorbed or released, m mass of the substance, c specific heat capacity of the substance, and ΔT change in temperature.

We can start by finding the amount of heat released by the metal:

q(metal) = m x c(metal) x ΔT(metal)

q(metal)= 10 g x c(metal)x (100°C - 35°C)

q(metal)= 650 g°C x c(metal)

We can also find the amount of heat absorbed by the water:

q(water) = m x c(water) x ΔT(water)

q(water)= 10 g x c(water) x (35°C - 20°C)

q(water)= 150 g°C x c(water)

Since the metal releases heat and the water absorbs heat, we know that q(metal) = -q(water) (i.e., the heat lost by the metal is gained by the water).

Therefore:

650 g°C x c(metal) = -150 g°C x c(water)

Solving for c(water), we get:

c(water) = -650/150 x c(metal)

c(water) = -4.33 x c(metal)

Since specific heat capacity is always positive, we know that c(water) is negative in this case. This indicates that water cannot have a negative specific heat capacity. Therefore, the metal has a higher specific heat capacity than water.

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Answer: 7.47 M

Explanation:

Molarity is moles/ liters

Liters= 0.75 L

moles = 325 g/58 g(mass from Periodic table for NaCl) =5.60 mole

5.60/0.75= 7.47

Santa Catarina is the tropical storm having wind speed range between 30-80°C that would experience more rainfall as it has more sustained surface wind speed.  

The maximum sustained surface wind speed for a tropical storm ranges from 39 to 73 mph. Due to Santa Catarina's proximity to the Atlantic Ocean, there should be an equal amount of water vapor in the air in the form of moisture in the breezes.

As a result, tropical cyclones mostly form in regions with temperatures between 5 and 30 degrees that are close to the equator. The closeness of Atlantic Ocean also causes tropical storms to form near the surface.

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Correct question is:

The temperature of the areas surrounding Santa Catarina before each storm was about 13°C, and there was the same amount of water vapor in the air. Given this information, which storm do you predict will have the most rainfall, and why?

(Refer the images for the phases of storms.)

Answer:

A the volume of the ballon will decrease

Explanation:

This is because the temperature decreased so the particles slowed down and need less room or volume to move around and collide in

The process that will likely result in a precipitation reaction is (b) mixing a BaCl2 solution with a K2SO4 solution.

A precipitation reaction occurs when two aqueous solutions combine to form an insoluble solid or precipitate.

The balanced ionic equation for this precipitation reaction is:

Ba2+ (aq) + SO42- (aq) → BaSO4 (s)K+ (aq) + Cl- (aq) → KCl (aq)

The net ionic equation for this precipitation reaction is:

Ba2+ (aq) + SO42- (aq) → BaSO4 (s)

The net ionic equation only includes the ions that take part in the reaction. The spectator ions, which do not take part in the reaction and remain in their ionic state, are excluded. In this case, K+ and Cl- are spectator ions.

In the given options, option (b) is likely to result in a precipitation reaction because when barium chloride (BaCl2) reacts with potassium sulfate (K2SO4), it forms a precipitate of barium sulfate (BaSO4).

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31,146.4 Joules of heat were applied to the beaker.

The amount of heat (q) required to heat a substance is given by:

q = m × c × ΔT

where:

m = mass of the substance

c = specific heat capacity of substance

ΔT = change in temperature

For water, the specific heat capacity (c) is 4.184 J/g°C.

The mass of water (m) is 100g.

The change in temperature (ΔT) is (99°C - 25°C) = 74°C.

Therefore, the amount of heat (q) required to heat the water is:

q = 100g × 4.184 J/g°C × 74°C

q = 31,146.4 J

Therefore, approximately 31,146.4 Joules of heat were applied to the beaker.

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There is no visible light emitted by stars. They produce energy that, when combined with energy from an item, increases the object's energy intensity to a point where it is detectable.

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Explanation:

To create the required 0.500 M HCl solution, Student A will need to measure 1.41 L of the 1.01 M HCl solution from the 2.5 L bottle and diluted it to 2.85 L with water.

To prepare 2.85 L of 0.500 M HCl solution, we need to determine the amount of HCl required.

Firstly, we need to calculate the molarity of the 37% HCl solution:

of HCl in 2.5 L Mass bottle = 2.5 L x 37 g/100 g = 0.925 kg

Molarity of HCl solution = (37 g/100 g) / 36.46 g/mol = 1.01 M

Now, we can use the following formula to determine the amount of 1.01 M HCl solution needed to prepare the 2.85 L of 0.500 M HCl solution:

M₁V₁ = M₂V₂

Where,

M₁ = Molarity of stock solution = 1.01 M

V₁ = Volume of stock solution needed

M₂ = Desired molarity of diluted solution = 0.500 M

V₂ = Volume of diluted solution = 2.85 L

Rearranging the formula to solve for V₁, we get:

V₁ = (M₂ x V₂) / M₁ = (0.500 M x 2.85 L) / 1.01 M = 1.41 L

Therefore, Student A will need to measure 1.41 L of the 1.01 M HCl solution from the 2.5 L bottle and dilute it to 2.85 L with water to prepare the desired 0.500 M HCl solution.

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Pb's crystal structure is more accommodating to solute atoms, allowing it to accommodate more Sn atoms. Sn atoms tend to cluster together and form distinct regions in a Pb-Sn alloy.

The ability of a solid solution to accommodate atoms of another element depends on the atomic size, crystal structure, and electronic configuration of both the solvent (major component) and the solute (minor component) atoms.

In the case of lead (Pb) and tin (Sn), they are both metallic elements with similar crystal structures and atomic radii. However, Pb has a more complex crystal structure than Sn, which allows for more spaces (interstices) for solute atoms to occupy. Additionally, Sn atoms have a greater atomic mass than Pb atoms, which means they have a stronger tendency to cluster together and form distinct regions within the microstructure.

Therefore, a sample of Pb can accommodate more Sn atoms in its microstructure compared to how many atoms of Pb a sample of Sn of the same size can accommodate because the crystal structure of Pb is more accommodating to solute atoms and the Sn atoms are more likely to cluster together and form distinct regions within the microstructure of a Pb-Sn alloy.

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The volume (in liters) of NO₂ present in 80.0 grams at STP is 38.98 L

We'll begin by obtaining the number of mole present in 80 grams of NO₂. Details below:

Mole of NO₂ = mass / molar mass

Mole of NO₂ = 80 / 46

Mole of NO₂ = 1.74 moles

Finally, we shall determine the volume at STP. Details below:

1 mole of NO₂ = 22.4 L at STP

Thus,

1.74 mole of NO₂ = 1.74 × 22.4

1.74 mole of NO₂ = 38.98 L

Thus, we can conclude that the volume of NO₂ is 38.98 L

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Answer:

There are several sources of errors when reading a thermometer. Some common sources include limitations in digital processing and physical issues with the device itself, errors with the sensor which is often the greatest source of error, and measurement error which can depend on the skill of the operator. An “Err” message can also appear on a thermometer’s display if the sensor is too warm before powering on, if the temperature reading is incomplete, or if there is an internal problem with the thermometer.

Answer:

Explanation:

1) 1; 1; 2

2) 2; 6; 2; 3

Answer: NH4NO3 ⟶ 2N2O + 4H2O (balanced equation)

Coefficients: 1, 2, 4

2Fe + 6HCl ⟶ 2FeCl3 + 3H2 (balanced equation)

Coefficients: 2, 6, 2, 3

Your welcome stranger. (:

The poster showing the primary colors are found in the attachment.

The primary colors of light are red, green, and blue. By combining these three colors in different ways, all other colors in the visible spectrum can be produced.

The primary colors of pigment are cyan, magenta, and yellow. By mixing these three pigments in different proportions, all other colors can be produced. It is important to note that the primary colors of pigment are different from the primary colors of light, which can sometimes cause confusion.

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The pH of a 0.47 M solution of carbonic acid is approximately 3.93.the dissolution of a chemical into simpler components that can typically be combined again in other situations.

Daydreaming, highway hypnosis, or "getting lost" in a book or movie are all instances of mild, everyday dissociation that include "losing touch" with awareness of one's immediate surroundings.

The first dissociation reaction of carbonic acid can be written as follows:

H₂CO₃ + H₂O ⇌ HCO₃⁻ + H₃O⁺

Ka1 = [HCO₃⁻][H₃O⁺]/[H₂CO₃]

Assuming x is the concentration of H₃O⁺ ion from dissociation of H₂CO₃, then the concentration of HCO₃⁻ ion will also be x.

Ka1 = (x)(x)/[H₂CO₃]

4.3 × 10⁻⁷ = x²/0.47

x = √(4.3 × 10⁻⁷ × 0.47) = 1.17 × 10⁻⁴ M

So, [H₃O⁺] = 1.17 × 10⁻⁴ M and [HCO₃⁻] = 1.17 × 10⁻⁴ M.

Now, let's consider the second dissociation reaction of carbonic acid:

HCO₃⁻ + H₂O ⇌ CO₃²⁻ + H₃O⁺

Ka2 = [CO₃²⁻][H₃O⁺]/[HCO₃⁻]

Assuming y is the concentration of H₃O⁺ ion from dissociation of HCO₃⁻, then the concentration of CO₃²⁻ ion will be y.

Ka2 = (y)(y)/[HCO₃⁻]

5.6 × 10⁻¹¹ = y²/(1.17 × 10⁻⁴)

y = √(5.6 × 10⁻¹¹ × 1.17 × 10⁻⁴) = 3.34 × 10⁻⁸ M

So, [H₃O⁺] = 1.17 × 10⁻⁴ M + 3.34 × 10⁻⁸ M = 1.17 × 10⁻⁴ M (since the second dissociation reaction is negligible compared to the first one)

The pH of the solution can be calculated as follows:

pH = -log[H₃O⁺] = -log(1.17 × 10⁻⁴) = 3.93

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