Phamistry IB Prep

• 8

• 16

• 5

• 7

Answer explanation

Try going from left to right according to compounds and count the number of atoms on both sides to double check.

• 13 atoms (O)

• 4 atoms (O)

Answer explanation

You go from moles to atoms (Na2CO3) to atoms (O).

11.
LiOH + KCl → LiCl + KOH 

b)  I actually produced 6 grams of lithium chloride and I began this reaction with 20 grams of lithium hydroxide. What is my percent yield?

• 16.9%
• 5.91%
• 1.88%
• 12.3%

CH₄ + 2 O₂ → CO₂ + 2 H₂O
How many moles of carbon dioxide are produced from the combustion of 110 g of CH₄?

• 13.7 mol
• 2.75 mol
• 6.11 mol
• 6.85 mol

N₂ +  3H₂ → 2NH₃ 
How many moles of hydrogen are needed to react with 2 moles of nitrogen?

• 6 mol H

• 2 mol H

• 3 mol H

• 1 mol H

9. Complete the equation for the percent yield of a chemical reaction:
Percent yield=(________)÷(________)×100%

• actual yield; theoretical yield
• theoretical yield; actual yield

What is the molar mass of C₆H₁₂O₆?

• 180.18 g/mol

• 180.12 g/mol

• 180.24 g/mol

• 180.06 g/mol

What is the measured amount of a product obtained from a chemical reaction?

• mole ratio
• theoretical yield
• percentage yield
• actual yield

 SiO₂ + 3C → SiC + 2CO
I need to add 8 moles of Carbon to the reaction. How many grams of Carbon should I weigh?

• _{96 g}
• 0.67 g
• 2.67 g
• 48 g

An aqueous solution of MgSO₄ is added to an aqueous solution of BaCl₂ to form BaSO₄ and MgCl₂. If 1.75 g of MgSO₄ and 2.75 g of BaCl₂ are used, calculate the mass of BaSO₄ produced after the reactant has completed. [Mr MgSO₄ = 120.4; BaCl₂ = 208.3; BaSO₄ = 233.4; MgCl₂ = 95.3]

• 2.03 g

• 1.96 g

• 3.08 g

• 1.50 g

Answer explanation

You need to find the limiting and excess reactants and find the amount of product you can make.