Chemical Reaction Test Review

Chemical Reaction Test Review

GRADED A+ (ACTUAL TEST ) Questions and Answers (Solved)

• States that matter is not created or destroyed in a chemical reaction; mass of the reactants = mass of the products; # of atoms in the reactants = # of atoms in the products

Answer: Law of Conservation of Mass

• Materials you start with in a chemical reaction; on the left side of arrow

Answer: -Reactants

• Materials resulting from a chemical reaction; on the right side of arrow

Answer: -Products

• Any combination of 2 or more atoms chemically bonded together

Answer: Molecule

• Molecule made up of the same type of atoms

Answer: Element

• Molecule made up of 2 or more different types of atoms

Answer: Compound

• Is Ag(silver) an atom or molecule?

Answer: Atom 1 / 2

• Is CH an element or a compound?

Answer: Compound - because it is made of 2 different elements -

carbon and hydrogen

• This tells how many atoms of an element are in a molecule

Answer: Subscript

• Number in front of a molecule that tells how many molecules there are (ex. 2CaCl)

Answer: Coefficient

• What is the only sure sign of a chemical reaction?

Answer: Creation of a new substance with different properties

from the original substances

• How do you find the number of molecules?

Answer: Look at the COEFFICIENT

• How do you find the number of atoms in a molecule?

Answer: Look at the SUB- SCRIPT then multiply that by the

COEFFICIENT (if there is one)

• What are signs of a chemical reaction? (there are about 7 questions on the test where you need to know this!)

Answer: gases (bubbling, foaming); color change; precipitate; light

formation; temperature change; formation of new substance

• How can you tell if an equation is balanced?

Answer: There will be the same number of atoms of each element

on both sides of the equation - MAKE A T-CHART!

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