2023-24 Physical Science Chapter 7 TEST

Which of the following is not evidence that a chemical change has occurred?

• change in color

• change in size

• distinct smell

• change in temperature

• change in composition

Identify the correctly balanced chemical equation for the following word equation: Magnesium metal burns in gaseous oxygen to produce magnesium oxide.

The chemical properties of the elements in a chemical reaction usually stay the same after the reaction.

• True

• False

When a chemical change takes place through a chemical reaction, there are usually no clear signs that one has happened.

• True

• False

What is a "mole" in chemistry?

• an equation

• a mass

• a quantity

• a ratio

Bubbles are evidence that a chemical reaction has definitely occurred.

• True

• False

The substances that enter into a chemical reaction are called

• Reactants

• Products

• Coefficients

• Ingredients

The number(s) placed in FRONT of a chemical formula within a chemical equation

• Reactants

• Products

• Coefficients

• Ingredients

The substances that are combined in a chemical reaction yield (or "result in") what?

• Reactants

• Product(s)

• Coefficients

• Ingredients

When balancing Chemical Equations, you may change the Coefficients as well as the subscripts for the elements involved in the equation.

• True

• False