Stoichiometry Quiz

When baking a cake, what does stoichiometry help you understand?

• The relationship between different types of flour and their origins.

• The precise amount of each ingredient needed and the amount of cake produced.

• The time it takes for the cake to bake.

• The energy consumed by the oven during baking.

When baking a cake, the ingredients must be mixed in specific proportions. This practice is an application of what fundamental law?

• The Law of Definite Proportions

• The Law of Multiple Proportions

• The Law of Conservation of Energy

• The Law of Conservation of Mass

When baking a cake, the recipe specifies 2 cups of flour, 1 cup of sugar, and 2 eggs. What do these measurements represent in terms of a balanced chemical equation?

• Ratios of volumes of gases involved in the baking process

• Ratios of representative particles (molecules of flour: molecules of sugar)

• Ratios of energy changes during the baking process

• Ratios of catalysts to reactants in the recipe

In the process of forming rust, represented by the reaction 4Fe (s) + 3O2 (g) → 2Fe2O3 (s), what is the mole ratio of iron (Fe) to oxygen (O2)?

• 4 mol Fe : 2 mol O2

• 2 mol Fe : 3 mol O2

• 4 mol Fe : 3 mol O2

• 1 mol Fe : 1 mol O2

Can the coefficients in a chemical equation for the combustion of gasoline be used to find the masses of gasoline and carbon dioxide produced?

• No, because coefficients only indicate the physical state of the substances

• No, because coefficients are arbitrary numbers

• Yes, but only if the reaction involves gases

• Yes, by using the coefficients to find the ratios of masses indirectly using molar mass

When a propane barbecue is used, what does the combustion of propane (C₃H₈) produce according to the given chemical equation?

• 3 CO₂ and 4 H₂O

• 2 CO₂ and 3 H₂O

• 3 CO₂ and 3 H₂O

• 4 CO₂ and 5 H₂O

Imagine you're at a barbecue and you're using propane (C₃H₈) for the grill. How many molecules of O₂ are required to completely combust one molecule of propane?

• 2 molecules

• 4 molecules

• 5 molecules

• 6 molecules

When a propane gas grill is used to cook for a backyard BBQ, and the propane (C₃H₈) burns in the presence of oxygen (O₂) producing carbon dioxide (CO₂) and water (H₂O), what does this process demonstrate in terms of the Law of Conservation of Mass?

• The mass of the reactants equals the mass of the products.

• The mass of the reactants is greater than the mass of the products.

• The mass of the products is greater than the mass of the reactants.

• The mass of the reactants and products cannot be determined.

In the process of baking a cake, what does the term 'mole ratios' refer to?

• The ratio of the masses of flour to sugar used in the recipe

• The ratio between the numbers of moles of baking soda to vinegar required for the cake to rise properly

• The ratio of the volumes of milk and eggs mixed into the batter

• The ratio of the number of atoms in each ingredient used in the cake

In a science class experiment, students are tasked with decomposing potassium chlorate (KClO3) to observe the release of oxygen. What is the balanced chemical equation for this decomposition?

• KClO3 (s) → KCl (s) + O2 (g)

• 2KClO3 (s) → 2KCl (s) + 3O2 (g)

• KClO3 (s) → KCl (aq) + O2 (g)

• 2KClO3 (s) → KCl (s) + O2 (g)