Reacting Mass Calculations 3

Calculate the mass of calcium that can react with 40 g of oxygen. (Equation: 2Ca + O₂ → 2CaO)

(a)  

Calculate the mass in grams of fluorine that reacts with 3.9 g of potassium. (Equation: 2K + F₂ → 2KF)

(a)  

Calculate the mass in grams, of nitrogen that reacts with 30 g of hydrogen. (Equation: N₂ + 3H₂ → 2NH₃)

(a)  

What mass of carbon dioxide is made when 7.2 g of pentane (C₅H₁₂) burns in oxygen? (Equation: C₅H₁₂ + 8O₂ → 5CO₂ + 6H₂O)

(a)  

What mass of potassium can react with 4.0 g of oxygen? (Equation: 4K + O₂ → 2K₂O)

(a)  

What mass of chlorine reacts with 8.1 g of aluminium? Use the equation: 2Al + 3Cl₂ → 2AlCl₃. (moles Al = 0.30 mol, moles Cl₂ = 0.45 mol, mass Cl₂ = 31.95 g)

(a)  

What mass of iron can be made from 20 kg of iron(III) oxide? Use the equation: Fe₂O₃ + 3CO → 2Fe + 3CO₂.

• 14000 g

• 15000 g

• 16000 g

• 17000 g

What mass of hydrogen is needed to react with 31.8 mg of copper(II) oxide? Use the equation: CuO + H₂ → Cu + H₂O.

• 0.00040 g

• 0.00080 g

• 0.00120 g

• 0.00160 g

5.95 g of hydrated cobalt(II) chloride CoCl₂.nH₂O decomposes to form 3.25 g of anhydrous cobalt(II) chloride on heating. Calculate the value of n.

(a)  

Fe + S → FeS

0.8 moles of Fe are allowed to react an excess of S. What is the mass of FeS produced?

(A_r of Fe = 56, A_r of S = 32)

• 25.6 g

• 44.8 g

• 70.4 g

• 88 g