5.12 Unit Test Chemical Reactions

Question: Methane burns in oxygen to yield carbon dioxide and water. The chemical formula for this reaction is CH4+2O2→CO2+2H2O.

What is the reactant, or what are the reactants, of this reaction?

Answer: oxygen and methane

Question: Carbon and oxygen combine to form carbon dioxide.

What are the products, or what is the product, in this chemical reaction?

Answer: carbon dioxide

Question: What does the law of conservation of mass say?

Answer: The mass of the products in a chemical reaction is equal to the mass of the reactants.

Question: Which equation is balanced?

Answer: 4P+5O2→2P2O5

Question: What type of chemical reaction is CH4+2O2→CO2+2H2O?

Answer: combustion

Question: What is usually released in a combustion reaction?

Answer: energy

Question: Hydrogen, when combined with oxygen in a chemical reaction, forms water.

Which type of chemical reaction is this an example of?

Answer: synthesis

Question: Which sentence best describes why MnSO4→MnO+SO3 is not a synthesis reaction?

Answer: The reaction has more than one product.

Question: MnSO4→MnO+SO3 is not a synthesis reaction.

What type of reaction is it?

Answer: decomposition

Question: Which statement about decomposition reactions is true?

Answer: Decomposition reactions are essentially the opposite of synthesis reactions.