Assessment - Chemical Reaction

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

A boiling pot with a lid on it to keep in the energy is what type of system?

• Closed system
• Open System

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

• change in shape
• melting
• formation of a gas
• dissolving

Which of the following describes a precipitate?

• a liquid forms when a block of metal is heated
• a solid forms when one liquid is poured into another
• a gas forms when a solid is placed in a liquid
• bubbles form when an acid is poured on a rock

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