Unit 6 Test Review

The Law of Conservation of Matter

• tells how many atoms of an element are contained in one molecule or formula unit.

• the starting materials in a chemical reaction

• the new substances that are formed in a chemical reaction

• A law stating that atoms are not created or destroyed during a chemical reaction.

Is the equation balanced?: 2H₂O + O₂ --> 4MgO + 3Fe

• yes

• no

Tags

NGSS.MS-PS1-5

The coefficient in 3H₂O is

• 6

• 5

• 2

• 3

Tags

NGSS.MS-PS1-1

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

• 3
• 6
• 12
• 24

Tags

NGSS.MS-PS1-1

Is this equation balanced?

• yes
• no
• Not enough information

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

What is the little number after an element in a chemical equation called.
Example: H₂

• Coefficient 
• Subscript
• Atom
• Equation

Element or compound?
H₂O

• element
• compound

How many HCl molecules do you need to balance this equation? 
Mg +  __HCl --->  MgCl₂ + H₂

• 1
• 2
• 3
• 4

Tags

NGSS.MS-PS1-5

Is this balanced?
Al + O₂ → 2Al₂O₃

• Yes
• No

Tags

NGSS.MS-PS1-5

How many Oxygens are in this molecule? 
(OH)₂

• 4
• 1
• 2
• 3