Stoichiometry Assessment

What is a mole ratio?

• A mole ratio is a measure of the mass of a substance in grams.

• A mole ratio is a conversion factor derived from the coefficients of a balanced chemical equation, used to relate the amounts of reactants and products.

• A mole ratio is the number of molecules in a mole of a substance.

• A mole ratio is a method to calculate the temperature of a chemical reaction.

What is a gram to mole conversion factor?

• A method to convert temperature from Celsius to Fahrenheit.

• A factor used to convert the mass of a substance (in grams) to the amount of substance (in moles) using its molar mass.

• A technique for measuring the volume of a gas at standard temperature and pressure.

• A calculation used to determine the density of a substance.

What is the relationship between moles and mass?

• mass (g) = moles × molar mass (g/mol)

• mass (g) = moles ÷ molar mass (g/mol)

• mass (g) = moles + molar mass (g/mol)

• mass (g) = moles - molar mass (g/mol)

What is stoichiometry?

• A branch of physics that studies motion and forces.

• The study of the properties and behavior of matter.

• The branch of chemistry that deals with the calculation of reactants and products in chemical reactions based on the conservation of mass.

• A method for measuring the temperature of chemical reactions.

What is the significance of significant figures in stoichiometry calculations?

• The number of significant figures in the answer is arbitrary and does not affect the result.

• The number of significant figures in the answer is based on the number of significant figures in the given data.

• Significant figures are only important in theoretical calculations, not in practical applications.

• Significant figures are used to round the final answer to the nearest whole number.

What is the role of molar mass in stoichiometry?

• Molar mass is used to determine the volume of a gas at standard temperature and pressure.

• Molar mass is used as a conversion factor to relate the mass of a substance to the number of moles in stoichiometric calculations.

• Molar mass is irrelevant in stoichiometric calculations and is only used in molecular biology.

• Molar mass is used to calculate the energy released in a chemical reaction.

What is the purpose of balancing a chemical equation?

• To increase the speed of a chemical reaction.

• To ensure that the law of conservation of mass is obeyed, meaning the number of atoms for each element is the same on both sides of the equation.

• To determine the temperature at which a reaction occurs.

• To identify the products of a chemical reaction.

When is it easier to solve stoichiometric problems?

• When both the reactant and product are given in moles.

• When the reaction is balanced.

• When the temperature is constant.

• When the pressure is high.

What must a gram to gram stoichiometry problem include?

• A gram to gram conversion factor only.

• A mole to mole conversion factor only.

• Both a gram to mole conversion factor and a mole to gram conversion factor.

• A mole to gram conversion factor only.

How do you determine the limiting reactant in a reaction?

• By measuring the temperature change during the reaction.

• By comparing the mole ratios of the reactants used in the reaction to the mole ratios in the balanced equation.

• By calculating the total mass of the reactants before the reaction.

• By observing the color change of the reactants during the reaction.