Chemical Reaction Word Problems

Alex saw a rusty old car in an abandoned lot. Because he had recently read about chemical reactions, he began to wonder how the rust formed. What happened to cause the rust on the steel car?

• Oxygen in the air chemically combined with the iron in the steel to form rust.

• A physical change took place in the steel of the car to form rust.

• Oxygen in the air reacted with the paint on the car and formed rust.

• A decomposition chemical reaction took place when the iron in the steel mixed with oxygen to form rust.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

After having studied chemical reactions in school, Jose knew that when oxygen and hydrogen gases combine in the correct amounts, the combination yields a new substance, water. Choose the words to finish the sentence.
The hydrogen and oxygen are ___________, while the water is the _________ .

• synthetic, polymers

• reactants, polymers

• products, synthetic

• reactants, products

Tags

NGSS.MS-PS1-5

After learning about the law of conservation of mass, Remy began to wonder about how to best test this law. She wanted to show that the amounts of matter did not change but produced an equal amount of a different kind of matter. What is the best way to study this law?

• in a homogeneous mixture

• in an open system

• in a heterogeneous mixture

• in a closed system

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

A student mixes vinegar and baking soda in a closed container. What type of reaction is occurring?

• A) Synthesis

• B) Decomposition

• C) Single replacement

• D) Double replacement

Tags

NGSS.MS-PS1-2

Which of the following is a balanced chemical equation for the reaction between hydrogen and oxygen to form water?

• A) @@ \ce{H2 + O2 -> H2O} @@

• B) @@ \ce{2H2 + O2 -> 2H2O} @@

• C) @@ \ce{H2 + 2O2 -> H2O2} @@

• D) @@ \ce{2H2 + 2O2 -> 2H2O2} @@

Tags

NGSS.MS-PS1-5

In a chemical reaction, the mass of the reactants is 50 grams. What should be the mass of the products according to the law of conservation of mass?

• A) 25 grams

• B) 50 grams

• C) 75 grams

• D) 100 grams

Tags

NGSS.MS-PS1-5

What is the role of a catalyst in a chemical reaction?

• A) It increases the temperature of the reaction.

• B) It decreases the temperature of the reaction.

• C) It increases the rate of the reaction without being consumed.

• D) It decreases the rate of the reaction by being consumed.

Which of the following is an example of an exothermic reaction?

• A) Melting ice

• B) Boiling water

• C) Combustion of gasoline

• D) Photosynthesis

Tags

NGSS.HS-PS1-4

What is the product of the reaction between hydrochloric acid and sodium hydroxide?

• A) Sodium chloride and water

• B) Sodium and water

• C) Chlorine gas and water

• D) Hydrogen gas and sodium chloride

Tags

NGSS.MS-PS1-2

A chemical reaction has reached equilibrium. What does this mean?

• A) The reactants are completely converted to products.

• B) The products are completely converted to reactants.

• C) The rates of the forward and reverse reactions are equal.

• D) The reaction has stopped.

Tags

NGSS.HS-PS1-6