Stoichiometry review

Why is it important to understand stoichiometry in chemistry?

• It helps in predicting the amounts of substances consumed and produced in chemical reactions.

• It allows chemists to memorize chemical equations more easily.

• It is only relevant for theoretical chemistry and not for practical applications.

• It simplifies the process of balancing chemical equations.

What is the significance of balancing a chemical equation?

• It allows for the creation of new elements.

• It ensures that the law of conservation of mass is obeyed, meaning the number of atoms of each element is the same on both sides of the equation.

• It helps in predicting the rate of a chemical reaction.

• It is necessary for the formation of ionic bonds.

What is the molar mass of sodium hydroxide (NaOH)?

• 30.00 g/mol

• 40.00 g/mol

• 50.00 g/mol

• 60.00 g/mol

What is the balanced equation for the reaction of sodium with water?

• 2 Na + 2 H2O → 2 NaOH + H2.

• Na + H2O → NaOH + H2.

• 2 Na + H2O → Na2O + H2.

• Na + 2 H2O → 2 NaOH.

How do you convert moles of a substance to grams?

• mass (g) = moles × molar mass (g/mol)

• mass (g) = moles ÷ molar mass (g/mol)

• mass (g) = moles + molar mass (g/mol)

• mass (g) = moles - molar mass (g/mol)

In the reaction Fe2O3 + 3H2 → 2Fe + 3H2O, how many moles of iron can be produced from 6 moles of H2?

• 2 moles of iron

• 4 moles of iron

• 6 moles of iron

• 8 moles of iron

What is the product of the reaction between sodium and water?

• Sodium chloride (NaCl) and oxygen gas (O2)

• Sodium hydroxide (NaOH) and hydrogen gas (H2)

• Sodium bicarbonate (NaHCO3) and carbon dioxide (CO2)

• Sodium sulfate (Na2SO4) and nitrogen gas (N2)

How many moles of oxygen are produced from the decomposition of 6.7 moles of KClO3?

• 8.4 moles of oxygen are produced.

• 10.1 moles of oxygen are produced.

• 12.5 moles of oxygen are produced.

• 9.0 moles of oxygen are produced.

What is the mole ratio in the reaction 2CO + O2 → 2CO2?

• 1:1:1 for CO:O2:CO2

• 2:1:2 for CO:O2:CO2

• 3:2:3 for CO:O2:CO2

• 1:2:1 for CO:O2:CO2

What is the balanced equation for the decomposition of potassium chlorate (KClO3)?

• 2 KClO3 → 2 KCl + 3 O2

• KClO3 → KCl + O3

• 2 KClO3 → KCl + 2 O2

• KClO3 + O2 → KCl + 2 O2