General Chemistry 1: Stoichiometry

N$_2$ + 3 H$_2$ $\longrightarrow$ 2 NH$_3$

How many grams of hydrogen are needed to produce 68 g of ammonia? (molar mass of NH$_3$ = 12.031 g/mol, the molar mass of H$_2$ = 2.015 g/mol)

2 Al + Fe$_2$O$_3$ $\longrightarrow$ Al$_2$O$_3$ + 2 Fe

An operation requires at least 86.0 g of Fe to be produced. What is the minimum mass in grams of Fe$_2$O$_3$ necessary to produce the desired amount of products? How much Al$_2$O$_3$ is produced as a side product?

MM of Fe$_2$O$_3$ = 159.489 g/mol

MM of Al$_2$O$_3$ = 101.961 g/mol

H$_2$SO$_4$ + 2 KOH $\longrightarrow$ 2 H$_2$O + K$_2$SO$_4$

How many moles of KOH are requred to make 3.0 moles of K$_2$SO$_4$ ?

N$_2$ + 3 H$_2$ $\longrightarrow$ 2 NH$_3$

If 5 moles of N$_2$ react with excess H$_2$ how many moles of NH$_3$ will the reaction yield?

N$_2$ + 3 H$_2$ $\longrightarrow$ 2 NH$_3$

If 5.0 grams of N$_2$ react with excess H$_2$ how many grams of NH$_3$ will the reaction yield?

2 Na + Cl$_2$ $\longrightarrow$ 2 NaCl

How many grams of Cl$_2$ are needed to react completely with 12.0 g of Na?

The theoretical yield for a reaction is 627.0 g of SF$_6$. An experiment only yields 627.8g. What is the percent yield?

P$_4$ + 5 O$_2$ $\longrightarrow$ 2 P$_2$O$_5$

Starting with 8.00 g P$_4$ and 8.00 g of O$_2$, how many grams of P$_2$O$_5$ will the reaction yield?

CuCl$_2$ + Zn $\longrightarrow$ ZnCl$_2$ + Cu

20.0 mL of 1.50 M CuCl$_2$ reacts with 3.00 Zn. How many grams of ZnCl$_2$ does the reaction yield?

3 F$_2$ + S $\longrightarrow$ SF$_6$

Sulfur hexafluoride, a very good indicator, is prepared by the reaction of sulfur with elemental fluorine. What mass of SF$_6$ can be produced from the reaction of 150 g of S with 650 g of F$_2$ ?

MM of F$_2$ = 38.00 g/mol

MM of SF$_6$ = 146.06 g/mol

4 H$_2$ (g) + CS$_2$ (g) $\longrightarrow$ CH$_4$ + 2 H$_2$S (g)

Methane and hydrogen sulfide form when hydrogen reacts with carbon disulfide. Identify the excess reagent and calculate the remaining mass after 36 L of H$_2$ reacts with 12 L of CS$_2$

Many metals react with oxygen gas to form the metal oxide. When solid calcium and oxygen gas react they form a metal oxide. You wish to calculate the mass of metal oxide that can be prepared from 4.20 g of Ca and 2.80 g of O$_2$

A. Predict the metal oxide product formed when solid calcium and oxygen gas react (include states of matter.) Balance the equation.

B. How many moles of product can be produced from the given mass of Ca?

C. How many moles of product can be produced from the given mass of O$_2$ ?

D. What is the limiting reactant?