Unit 2 Test

True or False: In a complete chemical equation, there must be the same number of atoms of each element on the reactants and products side.

• True

• False

Tags

NGSS.MS-PS1-5

Look at the chemical equation.

How many atoms of oxygen (O) are in the reactants?

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-1

Look at the chemical equation.

How many atoms of oxygen (O) are in the products?

Tags

NGSS.MS-PS1-5

The reactants are on the left side of the chemical equation.

• True
• False

Coal contains carbon and other elements. Carbon dioxide forms when coal burns in the presence of oxygen. Which of these is the best evidence that a chemical reaction occurs when coal burns?

• The shape of the coal changes
• Oxygen is present
• A new substance is produced
• Coal is made up of more than one element

Tags

NGSS.MS-PS1-2

Is hammering wood together to build a house a chemical or physical change?

• chemical
• physical

What is the left part of a chemical equation called?
H_{2 +} O → H₂O

• Reactants
• Products 
• Yields 
• Chemical Equation 

Is this balanced?
2HgO → 2Hg + O₂

• Yes
• No

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Is this balanced?
Al + O₂ → 2Al₂O₃

• Yes
• No

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

the starting materials in a chemical reaction

• Products
• Reactants
• Starters
• Enders