Chemistry Unit Test (2021)

What type of subatomic particles are found in the cloud surrounding the nucleus of an atom?

• neutrons

• electrons

• protons

• reactions

The atomic mass is calculated by adding __ and ___

• protons & electrons

• electrons in the cloud

• protons & neutrons

If two substances are mixed and a gas was produced, what is this a sign of?

• a physical change

• a chemical change

• no change

What happens if there is a temperature change when you mix two substances together?

• a physical change has occurred

• nothing has happened

• a chemical change has occurred

When two atoms bond together they make

• an element

• a compound

• a nucleus

Which of the following are examples of a physical change?

• all of these examples are physical changes

• ice melting

• freezing juice

• tearing paper

In a reaction A + B ----> C, reactant A has 5 grams and product C has 9 grams. How many grams should reactant B have?

• 4 g

• 5 g

• 9 g

• 14 g

Which of the following is the definition of an ionic compound?

• A transfer of electrons between a metal and a nonmetal

• A sharing of electrons between a metal and a nonmetal

• A transfer of electrons between a metal and a metal

• A sharing of electrons between a nonmetal and a nonmetal

Lithium and Sodium are both in Group 1 of the periodic table so they

• are both nonmetals and form covalent bonds

• have one energy level and similar properties

• have one valence electron and similar properties

Coefficients tell you the number of

• protons

• valence electrons

• atoms

• molecules