balancing atoms

How many Hydrogen are in 4H₂O?

• 6

• 8

• 2

• 4

How many Magnesium are in 10MgCl₂?

• 10
• 5
• 20

How many O's are in Al₂(SO₄)₃

• 4
• 12
• 7
• 24

What is a coefficient?

• The small number on the right of the chemical symbol.
• The large number to the left of a formula.

Is this equation balanced?

• yes
• no
• Not enough information

How many atoms of Carbon are in the compound C₂H₈O ?

• 8
• 2
• 1
• 11

Why is the following chemical equation not balanced?
H_{2 +} O₂ --> H₂O

• each side of the equation has a different number of oxygen atoms
• each side of the equation has a different number of hydrogen atoms
• each side has the same mass

Is the following equation balanced or unbalanced?
Fe + S --> FeS

• balanced
• unbalanced

Which of the following is an unbalanced equation?

• CaCO₃ --> CaO + CO₂

• PbO₂ + 2H₂-->2Pb + H₂O

• 2Na+ 2H₂O-->2NaOH + H₂

• CS₂ + 3O₂ --> CO₂ + 2SO₂

Balance this equation:
 2Li + Cl₂ -> LiCl

• 2Li + Cl₂ -> 4LiCl2
• 2Li + Cl₂ -> LiCl₂
• 2Li + Cl₂ -> 2LiCl