Unit 10 Flashcards
Which is the correct mole ratio of K3PO4 to KNO3 in the chemical reaction Mg(NO3)2 + K3PO4 →Mg3(PO4)2 + KNO3?
1:3
Which is the correct mole ratio for aluminum chloride to chlorine in the chemical reaction
AlCl3 + Br2 → AlBr3 + Cl2?
2:3
The calculation of quantities in chemical equations is called ____
Stoichiometry
What is the mass of potassium chloride when 2.50 g of potassium reacts with excess of chlorine gas?
4.77 g
How many liters of hydrogen gas are needed to react with CS2 to produce 2.50 L of CH4 at STP?
10 Liters
Mole ratio
A comparison of how many moles of one substance are required to participate in a chemical reaction with another substance, based on the balanced chemical equation
How to calculate percent yield
E/T x 100
Stoichiometry involves ____ _____.
Stoichiometry involves quantitative relationships.
Stoichiometric relationships are based on ____.
Stoichiometric relationships are based on mole quantities in a balanced equation.
When two substances react to form products, the reactant which is used up is called the ___.
Limiting Reactant
Which of the following is NOT true about limiting and excess reagents?
a. A balanced equation is necessary to determine which reactant is the limiting reagent.
b. The amount of product obtained is determined by the limiting reagent.
c. Some of the excess reagent is left over after the reaction is complete.
d. The reactant that has the smallest given mass is the limiting reagent.
D.
Methane
CH4
This quantity can always be used in the same way as moles when interpreting balanced chemical equations.
Number of molecules
This is conserved only in reactions where the temperature is constant and the number of moles of gaseous reactants is the same as that of gaseous products.
Volume
This is conserved in every ordinary chemical reaction.
Mass
The reactant that determines the amount of product that can be formed in a reaction
Limiting regeant
The maximum amount of product that could be formed from given amounts of reactants
Theoretical yield
The reactant that is not completely used up in a reaction
Excess regeant
The amount of product formed when a reaction is carried out in the laboratory
Actual yield
The ratio of the actual yield to the theoretical yield
Percent Yield
Stoichiometry steps (4)
- Check for Diatomics
- Balance the equation
- Convert to moles w/ gram formula mass
- Coefficient Formula: Multiply by moles find/ moles given
Limiting regrant steps (3)
- Check for Diatomics
- Balance the equation
- Convert to moles w/ gram formula mass
- Coefficient Formula: Multiply by moles find/ moles given
- Convert to mass of product w/ gram formula mass
Stoichiometry relies on ___.
The law of Conservation of Mass.
What can the coefficients mean? (3)
- Moles
- Atoms
- Molecules
