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What is the definition of chemical reaction?

• the input which reacts chemically to create product

• a system where none of the reactants or products are allowed to escape

• occurs when the atoms and molecules of two or more substances rearrange to form new substances

• the output, or result of a chemical reaction

What is a reactant in a chemical equation?

• the input which reacts chemically to create product

• the output, or result of a chemical reaction

• a small molecule that makes up one part of a polymer

• compounds made of thousands of repeating smaller molecules

What is a product in a chemical reaction?

• the input which reacts chemically to create product

• the output, or result of a chemical reaction

• a small molecule that makes up one part of a polymer

• compounds made of thousands of repeating smaller molecules

What will weigh more when a chemical change is complete?  The reactants before the chemical reaction, or the product after the reaction is complete?

• They both will weigh the same

• The product always weighs more than the reactant

• The reactant will weigh more than the product

• They both will loose mass after the reaction

Which of the following is a sign that a chemical reaction has occurred?

• change in shape

• melting

• formation of a gas

• dissolving

 A white baking soda solution was combined with white calcium chloride. Once combined the temperature increased, the substances bubbled, and were white in color. What indicators of a chemical change were shown?

• Temperature increase

• Color change

• Bubbling/fizzing

• Temperature increase and bubbling/fizzing

The law of conservation of mass states that matter cannot be created nor __________________.

• destroyed

• rearranged

• transferred

• changed

A __________________ chemical equation shows that the same number of atoms in the reactants are also in the product.

• balanced

• transferred

• rearranged

• beautiful

In a closed system, a chemical reaction takes place.  The mass of the reactants in the beginning of the reaction is 25g.  What does the mass have to be in the end of the reaction in order to follow the law of conservation of mass?

• 15 grams

• 25 grams

• 30 grams

• You can't tell with the given information.

In a chemical reaction, the mass of the reactants was 15g.  The mass of the products was 12g.  Did this chemical reaction follow the law of conservation of mass?

• Yes

• No

• You can't tell with the given information.