Chemistry final exam

Which branch of chemistry deals with the mass relationships of elements in compounds and the mass relationship among reactants and products in chemical reactions?

Stoichiometry

A balanced equation allows one to determine the

Mole ratio of any two substances in the reaction

Which coefficients correctly balance the formula NH4NO2 - N2+H2O?

1,1,2

When the formula equation Fe3O4+Al - Al2O3 + Fe is correctly balanced the coefficient of Fe is number

9

In the reaction N2+3H2 - 2NH3 what is the mole ratio of hydrogen to ammonia?

3:2

To completely convert 9.0 mol hydrogen to ammonia gas, how many moles of nitrogen gas are required?

3.0 mol

In the equation 2KClO3 - 3O2 How many moles of oxygen are produced when 3.0 moles of KClO3 decompose completely?

4.5 mol

For the reaction represented by the equation 2H2 + O2 - 2H2O, how many moles of oxygen are produced when 3.0 mol of KClO3 decompose completely?

12 moles

N2+3H2 - 2NH3, how many moles of N are required to produce 18 mol of ammonia

9.0 mol

2H2 + O2 - 2H2O, how many grams of water are produced from 6.00 mol of hydrogen?

108g

How many grams of magnesium nitrate are produced from 8.00 moles of HNO3 and an excess of Mg(OH)2?

593g

How many grams of hydrogen are produced if 120g of sodium and 80g of water are available?

4.5g

Which reactant controls the amount of product formed in a chemical reaction?

Limiting reactant

What is the ratio of the actual yield to the theoretical yield multiplied by 100%?

Percentage yield

Calculate the percentage yield if 500g of sulfur trioxide react with excess water to produce 575g of sulfuric acid.

93.9%

Calculate the percentage yield of carbon dioxide if 1000g of methane react with excess oxygen to produce 2300g of carbon dioxide.

83.88%

According to the kinetic molecular theory, particles of matter are in motion in

Solid, liquids, and gases

An ideal gas is a hypothetical gas

That conforms to all of the assumptions of the kinetic theory

Unlike in an ideal gas, in a real gas

The particles exert attractive forces on eachother

According to the kinetic-molecular theory, particles of an ideal gas

Neither attract nor repel each other but collide

What determines the average kinetic energy of the molecules of any gas?

Temperature

What is an example of effusion?

Air slowly escaping from a pinhole in a tire

Under which conditions do real gases most resemble ideal gases?

Low pressure and high temperatures

The intermolecular forces between particles in a liquid can involve all of the following except

Gravitational forces

The particles in a liquid are usually

Closer together and lower in energy than those in a gas

Which term best describes the process by which particles escape from the surface of a nonboiling liquid and enter the gas state

Evaporation

Why would a camper near the top of Mt. Everest find that water boils less than 100’C

There is less atmospheric pressure than at sea level

Glycerol boils at a slightly higher temperature than water. This reveals that glycerols attractive forces are

Stronger than those of water

During boiling, the temperature of a liquid

Remains constant

Why doesn’t water in lakes and ponds of temperate climates freeze solid during the winter and kill nearly all the living things it contains

Ice floats

What is the SI unit of force?

Newton

Which instrument measures atmospheric pressure?

Barometer

A pressure of 745 mm Hg equals

745 torr

Convert the pressure 1.30 atm to kPA

132 kPA

Standard temperature is exactly

0’C

Who developed the concept that the total pressure of a mixture of gases is the sum of their partial pressures?

Dalton

A mixture of four gases exerts a total pressure of 860 mm Hg. Gases A and B each exert 220 mm Hg Gas C exerts 110 mm Hg. What pressure is exerted by gas D?

310 mm Hg

What is the partial pressure of water vapor in oxygen gas collected by water displacement at 10’C and 750 mm Hg?

9.2 mm Hg

A sample of gas is collected by water displacement at 600.0 mm Hg and 30’C. What is the partial pressure of the gas?

568.2 mm Hg

A sample of oxygen occupies 560 mL when the pressure is 800.00 mm Hg. At constant temperature, what volume does the gas occupy when the pressure decreases to 700.0 mm Hg?

640 mL

The volume of a gas is 5.0 L when the temperature is 5.0’C. If the temperature is increased to 10.0’C without changing the pressure, what is the new volume?

5.1 L

on a cold winter morning when the temperature is -13’C, the air pressure in an automobile tire is 1.5 atm. If the volume doesn’t change, what is the pressure after the tire has warmed to 15’C?

1.7 atm

The pressure of a sample of gas at 10.0’C increases from 700. Mm Hg to 900 mm Hg. What is the new temperatre

90.0’C

The volume of a sample of oxygen is 300.0 mL when the pressure is 1.00 ATM and the temperature is 21°C at what temperature is a volume 1.00 L and the pressure 0.500 ATM

227’C

When gay lussacs law of combining volume holds, which of the following can be expressed in ratios of small whole numbers?

Volumes of gaseous reactants and products

If 0.5 L of O2 reacts with H2 to produce 1 L of H2O what is the volume of H2O obtained from 1 L of O2

2 L

The equation for the production of methane is C plus 2H2 equals CH4 how many liters of hydrogen are needed to produce 20 L of methane

40. L

The the principle that under similar pressures and temperatures equal volume of gas is contain the same number of molecules is attributed to

Graham

The standard molar volume of a STP is

22.4 L

A 1.00 L sample of a gas has a mass of 1.92 g at STP. What is the molar mass of the gas?

43.0 g/mol

All of the following equations or statements of the ideal gas law, except

p=nRTV

What is the value of the gas constant?

0.0821 L X atm/ mol x K

Calculate the approximate volume of a 0.600 mole sample of a gas at 15°C in a pressure of 1.10 ATM

12.9 L

I gas sample with a mass of 12.8 g exerts of pressure of 1.2 ATM at 15°C in the volume of 3.94. What is the molar mass of the gas?

64 g/mol

How many times greater is the rate of a fusion of molecular fluorine than a molecular bromine at the same temperature and pressure?

2.051

What is the ionic equation for the reaction between sulfuric acid and an aqueous potassium hydroxide?

H+ + OH- — H2O(l)

Which of the following is not a colligative property of a solution?

Supersaturation

How many moles of ions are produced by the dissociation of one mole Al2(CO3)3

5 mol

The separation of ions that occurs when an ionic compound dissolves is called

Dissociation

Champions formula for the hydronium iron

H30+

Which of the following is a strong elect

HBr

Colligative properties depend on

The concentration of the solute particles

, which of the following usually makes a substance dissolve faster in a solvent

Agitating the solution

Which of the following pairs of factors affect the solubility of a particular substance

And the nature of the solute and solvent

If a crystal added to an acquiesce solution, causes many particles to come out of the solution, the original was

Super saturated I’ve never been to one of these before I think about how many people

Which of the following occurs as temperature increases

Solubility increases

What happens to the solubility of a gas in a liquid if the partial pressure of the gas above the liquid decreases

The solubility decreases

What is a molarity of a solution that contains six moles of solute in 2 L of solution

3M

What is a molarity of a solution containing 7.0 moles of solute is 569 mL of solution

12M

What is the molarity of a 200 mL of solution in which 2.0 moles of sodium bromide is dissolved

10M

What is the molarity of a solution containing 56 g of solute in 959 mL of solution

2.2M

what mass of sucrose C12H22O11 is needed to make 500.0 mL of a 200M solution

34.2 g

Describes liquids that are insoluble in one another

immiscible

Solution containing maximum amount of solute

Saturated solution

Solution containing more solute than can theoretically dissolve at a given temperature

Supersaturated solution

At a given temperature, the solubility of a gas and a liquid is directly proportional to the pressure of the gas above the liquid

Henry’s law

Measure of the amount of solute dissolved in a specific quantity of solvent

Concentration

Colloid particles

Scatter light, but some gets through and cannot be filtered

Suspended particles

Scatter light, doesn’t get through can be filtered, bigger

Explain why a soft drink loses its fizz after it has been open and left without a lid on its container

Because it loses CO2, which has escape the can now the liquid is just a sugary solution that has gone flat

acids taste

Sour

Acid generally release H2, gas when they react with

Active metals

Bases taste

Bitter

Which of the following is a binary acid?

HBr

Which acid is used in batteries

Sulfuric acid

Which of the following did arrhenius theorize?

Because acids and bases carry electric current, they must produce ions in a solution

A substance that ionizes nearly completely an aqueous solutions and produces H30+ is a

Strong acid

Whose definitions of acids and bases emphasizes the role of protons

Bronsted and Lowry

In the equation HCL + H2O = H30+ + Cl- which species is a bronsted lowry acid

HCL

a lewis acid is

An electron pair acceptor

A conjugate acid is a species that

Is formed by the addition of a proton to a base

In the reaction represent by the equation HF+ H20 = H30+ + F- a conjugate acid is

H30+ and H20

In the reaction represented by the equation HClO3 + NH3 = NH4+ + ClO-3 the conjugate acid of NH3 is

HClO3

In the reaction represented by the equation CH3COOH + H2O = H3O+ +CH3COO- , the conjugate base of H3O+ is

CH3COO-

The conjugate of a strong base is a

Weak acid

H2O is a weak base and H3O+ is a

Strong acid

An amphotheric species is one that reacts as a

Acid or a base

The ion HSO-4 acts as an

Acid

The molecule H2O acts as a

Base

The substances produced when KOH(aq) neutralizes HCl (aq) are

KH2O+(aq) and Cl-(aq)