Knowledge Check- Intro to Reactions

When balancing equations a ____ can be placed to the left of a formula of a substance to make the equations balanced

• charge
• subscript
• random number
• coefficient

The substances at the beginning of a chemical reaction are called the ____

• product
• yield
• chemical symbol
• reactants

What is the part of the chemical equation in green called? 
Fe + S --> FeS

• products
• reactants
• yield
• chemical formula

How many atoms of aluminum are on each side of the following equation: 4Al + 3O₂ --> 2Al₂ O₃

• 2
• 6
• 1
• 4

What is the Law of Conservation of Mass?

• It states that no matter can be created or destroyed.

• It states that no energy can be created or destroyed.

• It states that matter can be created or destroyed.

What is a coefficient?

• The small number on the right of the chemical symbol.

• The large number in front of a chemical formula.

• The number in between the chemical symbols.

What is the little number after an element in a chemical equation called.

Example: H₂

• Coefficient

• Subscript

• Atom

What is the arrow in a chemical equation...

H_{2 +} O ---> H₂O

• Reactants

• Products

• Yields

When balancing equations a _______________ can be placed to the left of an element to balance the equation

• charge

• subscript

• coefficient

How many atoms of carbon (C) are in C₆H₁₂O₆?

• 3

• 6

• 24