Chem 3 Quiz Actual

What are the products for the following equation?

2Al + 2CuCl --> 2Cu + 2AlCl

• 2Al + 2CuCl

• 2Cu + 2AlCl

• 2Cu + 2Al

• 2AlCl + 2CuCl

We use _________________ to show that a chemical reaction has occurred.

• chemical symbols

• atomic numbers

• chemical formulas

• chemical equations

The portion of the chemical equation on the right of the arrow is called ____________.

• reactants

• yields

• products

• elements

The portion of the chemical equation on the left of the arrow is called ____________.

• reactants

• yields

• products

• elements

According to the Law of Conservation of Matter, how does the mass of the products in a chemical reaction compare to the mass of the reactants?

• There is no relationship.

• The mass of the products is sometimes greater.

• The mass of the products is sometimes less.

• The masses are always equal.

The formula for rust is Fe₂O₃ What does that mean?

• There are three iron and three oxygen atoms.

• There are six iron and six oxygen atoms.

• There are two iron and three oxygen atoms.

• There are three iron and two oxygen atoms.

How are the formulas for Oxygen Gas and Carbon Dioxide Gas similar?

• They both have 3 atoms.

• They both have 2 oxygen atoms

• They both have 3 atoms.

• They both have 2 elements..

Which of the following always occurs in a chemical change?

• a new substance is formed

• heat is absorbed

• heat is released

• electricity is formed

When you make an omelet, which of the following processes is a chemical change?

• melting butter

• chopping onions

• frying eggs

• adding salt

Water vapor in the air turns to liquid water in the form of rain. This is an example of ....

• a chemical reaction, because the water is reacting with the air

• a physical change, because water is changing from a gas to a liquid

• a physical change, because you can see rain but not water vapor

• a chemical change, because the vapor is changing from a vapor to a gas