Chemistry Test: Stoichiometry
Describe the steps necessary to solve a mass-mass stoichiometry problem.
In order to solve a mass-mass stoichiometry problem using a balanced equation and knowing the mass/mol ratio of each element, you need to convert the initial mass into moles, multiply by the mole to mole ratio, and then convert back into grams giving the final answer.
The coefficients in a chemical equation represent the...
Relative mole amounts of each substance
How does the actual yield of a chemical reaction compare to the theoretical yield?
The actual yield is usually lower than the theoretical yield due to a number of reasons, including things like side reactions, dispersal into the atmosphere, and measurement errors.
Explain the difference between a limiting reactant and an excess reactant.
The limiting reactant in a reaction will keep the excess reactant(s) from creating any more of the certain product. Once the limiting reactant has been all used up, you can't create more of the product.
The measured amount of a product of a reaction is called the ____________________.
actual yield
What is the measured amount of a product obtained from a chemical reaction?
actual yield
The proportions of the reactants and products involved in a chemical reaction are shown by the ____________________ in the balanced chemical equation describing the reaction.
coefficients
The substance not completely used up in a chemical reaction is known as the...
excess reactant
The substance that is not used up completely in a chemical reaction is the ____________________.
excess reactant
Actual yield must be determined by...
lab result
A chemical reaction involving substances A and B stops when B is completely used. B is the...
limiting reactant
The substance that controls the quantity of product that can be formed in a chemical reaction is the _________________.
limiting reactant
The substance that restricts the participation of other reactants in a chemical reaction is known as the...
limiting reactant
The actual yield of a chemical reaction is In the chemical equation wA + xB → yC + zD, a comparison of the number of moles of A to the number of moles of C would be a...
mole ratio
The ratios obtained from the coefficients of substances in a balanced chemical equation are called ____________________ because they can be used to convert moles of one substance to moles of another substance.
mole ratio
If one knows the mass and molar mass of reactant A and the molar mass of product D in a chemical reaction, one can determine the mass of product D produced by using the...
mole ratio between A and D(balanced equation and stoichiometry)
A balanced chemical equation allows one to determine the...
mole ratio of any two substances in the equation
Why should you use moles in stoichiometry problems?
molecules are two small to count as they are so we convert them into a bigger unit(moles) and then convert them back to grams or molecules
The efficiency of a reaction is described by the ____________________ yield.
percent
The ratio of actual yield to theoretical yield * 100% is called the _________________________.
percent yield
What is the ratio of the actual yield to the theoretical yield, multiplied by 100%?
percent yield
To determine the limiting reactant in a chemical reaction, one must know the...
product through stoichiometry of each reactant
The branch of chemistry that deals with the numerical relationship of elements and compounds as reactants and products in a chemical reaction is known as _________________.
stoichiometry
