Chemistry second semester

The reactant that limits the extent of the reaction is called the

The reactant that limits the extent of the reaction is called the

Limiting reactant

The what of a chemical reaction is the amount of product produced by the reaction in reality

Actual yield

What is a ratio between the number of moles of any two substances in a balance chemical equation?

Mole ratio

If a portion of reactant remains after the reaction is completed, then that reacting is said to be the

Excess reactant

The what is the maximum amount of product that can be produced from a given amount of reactant

Theoretical yield

What is the study of the numerical relationships between products and reactants and a chemical reaction?

Stoichiometry

The what of a reaction gives the ratio of the actual yield to the theoretical yield

Percent yield

The amount of product formed during a reaction depends on the

Limiting reactant

Rarely does the actual yield of a reaction equal the

Theoretical yield

A balance chemical equation allows one to determine the

Mole Ratio of any two substances in the reaction

Actual yield must be determined by

Experiments

How many mole ratios can be correctly obtained from the chemical equation 2Al 203–» 4Al +302

6

fewer steps are required to solve stoichiometry problems when

The reactant is given in moles, and the product is sought in mole

The participation of reactants in a chemical reaction is controlled by the

Limiting reactant

For a chemical reaction percentage yield represents the

Efficiency

The limiting reactant of a reaction can be used to calculate the

Theoretical yield

In most chemical reactions, the amount of product obtained is

Less than the theoretical yield

Knowing the mole ratio of a reactant and product in a chemical reaction would allow you to determine

The mass of the product produced from a known mass of reactant

If a chemist calculates the maximum amount of product that could be obtained in a chemical reaction he or she is calculating the

Theoretical yield

The kinetic molecular theory of gases assumes that the particles of an ideal gas are separated by great distances. This implies that the gas particles are considered to have no definite

Volume

According to the equation for the kinetic energy of a moving object which gas would have the lowest average velocity, assuming all gases are at the same temperature

O3

Sublimation involves changing from a

Solid to a gas

Liquids and solids are much denser than gases because the particles of liquids and solids have a

Closer arrangement

An increase in pressure exerted on a liquid does not compress the liquid as much as the same increase in pressure compresses a gas because

Particles are more closely packed in liquids

When there is a small decrease in temperature, the average kinetic energy of the particles of a liquid

Decreases

the movements of particles in solids can best be described as

Vibrational

Amorphous solids behave like liquids at certain temperatures because of their

Random arrangement

Which of the following is true for the melting and freezing points of a pure substance

The melting point is the same as the freezing point

A phase diagram relates the state of matter, pressure and

Temperature

On a phase diagram the point at which all equilibrium lines join is the

Triple point

According to the equation of kinetic energy, if hydrogen molecules and oxygen molecules are at the same temperature hydrogen molecules have

Higher average speeds

As atmospheric pressure on the surface of a liquid decreases it’s boiling point

Decreases

Which of the following is an assumption of the kinetic molecular theory of gases?

The temperature of a gas depends on the average kinetic energy of the gas particles

If a gas has the same temperatures throughout which gas molecule has the highest average velocity

H2

Rates of effusion of different gases are proportional to their

Particle velocities

Which dates of matter are fluid?

Gases and liquids

A liquid can be described as a form of matter that

Has a definite volume

According to the kinetic molecular theory particles in a liquid

Move around randomly and constantly

Which of the following is not an example of an intermolecular force?

Gravitational forces

Surface tension does not account for which of the following phenomena

Ability to diffuse

A liquid becomes a gas during

Evaporation

If energy as heat is removed, most liquids will eventually

Freeze

The three states of matter of a particular substance in order of the strength of intermolecular forces from least to greatest are

Gas, liquid, solid

Which is an example of an amorphous solid

Glass

Which of the following is not a physical property of crystalline solids?

High compressibility

Which is an example of a polar covalent molecular crystal

H2O

The bonds that link water molecules together are said to be

Hydrogen bonds

what is the reason for the relatively low density of ice?

Empty spaces between molecules

Which of the following statements is true?

Particles of a gas collide with each other in elastic collisions

Which is not an assumption of the kinetic molecular theory

All the gas particles in a sample have the same velocity

the theory that describes the behavior of gases in terms of the motion of gas particles is

The kinetic molecular theory

Explain what would happen to the column of mercury in a barometer if the atmospheric pressure fell

As the pressure falls, the column of mercury will drop lower

Which of the following molecules can form hydrogen bonds

NH3

In a polar molecule which atoms will have the greatest partial negative charge

The most electronegative atom

Which intermolecular force depends on the formation of a temporary dipole

Dispersion forces

The unit cell of a crystalline solid is

Always cubic

The phase change that describes the direct conversion of a solid into a gas is

Sublimation

Dry ice is solid carbon dioxide. What combination of factors can change dry ice into a liquid

Increase both temperature and pressure

In a container filled with one mole of helium and one mole of nitrogen. The pressure in the container is primarily

The sum of the pressures exerted by nitrogen and helium

Avogadros principle

Equal volumes of gases at the same temperature and pressure contain equal numbers of particles

Molar volume

One mole of any gas will occupy a volume of 22.4 L at STP

Ideal gas constant

Represents the relationship among pressure volume temperature and number of moles of gas present

Combined gas law

Temperature pressure and volume are related for a fixed amount of gas

Ideal gas law

The physical behavior of an ideal gas can be expressed in terms of the pressure volume temperature, and number of moles of gas present

Gay-Lussacs law

The pressure of a given mass of gas varies directly with the kelvin temperature when the volume remains constant

Boyles law

The volume of a given amount of gas held at a constant temperature varies inversely with the pressure

Charles’s law

The volume of a given mass of gas is directly proportional to its kelvin temperature at constant pressure

What is the percent by mass of NaCl in a solution that contains 17.5 g NaCl per 500.0 g of water

3.38%

Sucrose dissolves in water because

Both water and sucrose are polar molecules

The decrease in solubility of a gas in a solution when the pressure is reduced it described by

Henry’s law

Which is a weak acid

HF

Which of the properties listed below is not characteristic of an acid

A slippery feel

Bases taste

Bitter

gas is added to a soccer ball. the pressure

increases

an inflated balloon is placed in a refrigerator. the volume

decreases

Dry ice is sealed in a plastic bag as the temperature increases the amount of gas present in the bag

Increases

Compressed air and scuba tanks cools off as a diver swim at deeper levels the pressure in the tank

Decreases

The volume of an inflated balloon increases when the amount of gas in the balloon

Increases

A person sits on an air mattress the pressure

Increases

Titrant

a solution of known concentration used to titrate a solution of unknown concentration

titration

the process in which an acid-base neutralization reaction is used to determine the concentration of a solution of unknown concentration

neutralization reaction

a reaction in which an acid and a base react in aqueous solution to produce a salt and water

end point

the point at which the indicator that is used in a titration changes color

equivalence point

the point at which the moles of hydrogen ions from the acid equal moles of hydroxide ions from base

acid-base indicator

a chemical dye whose color is affected by acidic and basic solutions