Question

Stoichiometry

P4+ 6Cl2➞ 4PCl37.
What mass, in grams, of phophorus trichloride will be produced from 85.0 g P 4 ?

2KNO3➞ 2KNO2+ O2
When 35.75 g potassium nitrate decompose, how many moles of potassium nitrite are formed?

AlCl3+ 3NH4F ➞ AlF3+ 3NH4Cl
If 9.75 g ammonium fluoride is reacted with an excess of aluminum chloride, how many grams of aluminum fluoride can be produced?

___H2SO4➞ ___H2O + ___SO3
How many grams of water will be produced from the decomposition of 78.5 g sulfuric acid (H2SO4)?

Be + 2 HCl ➞ BeCl2+ H2
If this single replacement reaction is started with 10.7 g HCl, how many moles of beryllium chloride will form?

2 CuS + 3 O2➞ 2 SO2+ 2 CuO
When this reaction is run with 74.5 g copper (II) sulfide, what mass, in grams, of copper (II) oxide will be produced?

Fe2O3+ 2 Al ➞ Al2O3+ 2Fe
If 35.60 g iron (III) oxide react with aluminum, how many grams of aluminum oxide will form?

2 LiOH + MgCl2➞ 2 LiCl + Mg(OH)2
When this reaction is run with 0.765 mol LiOH, how many moles of magnesium hydroxide will be produced?

Answer 1

1.

- First, calculate the molar mass of P4:

P4 = 4 x 30.97 g/mol = 123.88 g/mol

- Next, convert the given mass of P4 to moles:

85.0 g P4 x (1 mol P4/123.88 g P4) = 0.686 mol P4

- Then, use stoichiometry to find the moles of PCl3 produced:

0.686 mol P4 x (4 mol PCl3/1 mol P4) = 2.74 mol PCl3

- Finally, convert the moles of PCl3 to grams:

2.74 mol PCl3 x (137.33 g/mol) = 376 g PCl3

- So 376 grams of PCl3 will be produced.

2.

- First, calculate the molar mass of KNO2:

KNO2 = 101.11 g/mol

- Next, use stoichiometry to find the moles of KNO2 produced:

35.75 g KNO3 x (1 mol KNO2/2 mol KNO3) = 0.198 mol KNO2

- So 0.198 moles of KNO2 will be produced.

3.

- First, calculate the molar mass of NH4F and AlF3:

NH4F = 37.04 g/mol

AlF3 = 83.98 g/mol

- Next, use stoichiometry to find the moles of AlF3 produced:

9.75 g NH4F x (1 mol NH4F/57.04 g NH4F) x (1 mol AlF3/3 mol NH4F) = 0.0575 mol AlF3

- Finally, convert the moles of AlF3 to grams:

0.0575 mol AlF3 x (83.98 g/mol) = 4.83 g AlF3

- So 4.83 grams of AlF3 will be produced.

4.

- First, calculate the molar mass of H2O:

H2O = 18.02 g/mol

- Next, use stoichiometry to find the moles of H2 produced:

4.50 mol H2O x (2 mol H2/1 mol H2O) = 9.00 mol H2

- Finally, convert the moles of H2 to grams:

9.00 mol H2 x (2.02 g/mol) = 18.2 g H2

- So 18.2 grams of H2 will be produced.