8.2 Discussion: stoichiometry

2 KClO₃ → 2 KCl + 3 O₂
How many moles of oxygen are produced when 6.7 moles of KClO₃ decompose completely?

• 6.7 mol
• 1.0 mol
• 10.1 mol
• 4.5 mol

From the reaction: B₂H₆ + 3O₂ -->2 HBO₂ + 2 H₂O

What mass of O₂ will be needed to burn 36.1 g of B₂H₆?

B₂H₆ = 27.68 g/mol

• 13.8 g O₂

• 3.91 mol of O₂

• 125 g O₂

• 41.7 g O₂

Using the balanced chemical equation:

2C₄H₁₀ + 13O₂ --> 10H₂O + 8CO₂

Calculate the number of grams of C₄H₁₀ needed to produce 5.12 moles of CO₂.

• 58.0 g C₄H₁₀

• 2.56 g C₄H₁₀

• 74.2 g C₄H₁₀

• 37.19 g C₄H₁₀

If 1.2 × 10²³ particles of CH₄ are reacted, how many liters of HCN will be produced at STP? Round your answer to 2 decimal places.

CH₄ + NH₃ → HCN + 3 H₂

Mathematical Equivalence

ON

Answer explanation

At STP, 1 mole of HCN will occupy 22.4 liters of volume. Since 1.2 × 1023 particles of CH4 is equal to 6.0 × 1022 moles of CH4, 6.0 × 1022 moles of HCN will be produced. Therefore, the total volume of HCN produced at STP will be 6.0 × 1022 × 22.4 = 1.35 × 1024 liters.

2 Pb(NO₃)₂ → 2 PbO + 4 NO₂ + O₂

If 34.559 liters of O₂ are produced at STP, how many moles of Pb(NO₃)₂ were reacted? Round answers to 2 decimal places

Mathematical Equivalence

ON

2 SO₃ → 2 SO₂ + O₂

If 94.98 grams of SO₂ are produced, how many grams of SO₃ were reacted? Round to the correct number of significant Figures.

Mathematical Equivalence

ON

HC₂H₃O₂ + RbOH → RbC₂H₃O₂ + H₂O

If 17.55 grams of RbOH are reacted, how many grams of HC₂H₃O₂ will also be reacted? Round your answer to the correct number of sig-fig.

Mathematical Equivalence

ON

H₂ + CO₂ → H₂O + CO

If 2.7 × 10²³ particles of CO₂ are reacted, how many grams of CO will be produced? Round to the correct number fo sig figs.

Mathematical Equivalence

ON

2 C₂H₂ + 5 O₂ → 4 CO₂ + 2 H₂O

If 3.1384 moles of C₂H₂ are reacted, how many particles of H₂O will be produced? Round you answer to the correct number of sig figs.

Mathematical Equivalence

ON

2 KI + Cl₂ → 2 KCl + I₂

If 1.085 liters of Cl₂ are reacted at STP, how many particles of KCl will be produced? Round your answer to the correct number of sig figs.5.832

Mathematical Equivalence

ON