Balancing of Chemical Equations

Which problem is balanced?
(Check ALL answers)

• PbO₂ + 2H₂

• SO₂ + H₂0 --> H₂SO₄

• 2Na + 2H₂O --> 2NaOH + H₂

Tags

NGSS.HS-PS1-7

Balance this equation

_Al +_HCl --> _H₂ +_AlCl₃

• 2,6,3,2

• it's already balanced

• 4,12,3,4

• 2,1,4,5

Tags

NGSS.HS-PS1-7

Is the following equation balanced?
4Fe + 3O₂ --> 2Fe₂O₃

• yes

• no

Tags

NGSS.HS-PS1-7

Is the following reaction balanced?
2CH₃OH + 3O₂ --> 2CO₂ + 4H₂O

• yes

• no

Tags

NGSS.HS-PS1-7

A chemical reaction is balanced when

• both sides have the same elements

• Both sides have the same  number of atoms

• Same subscripts

• Same coefficients

Tags

NGSS.HS-PS1-7

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.

• The number behind a chemical formula.

Is this balanced?
Al + O₂ → 2Al₂O₃

• Yes

• No

Tags

NGSS.HS-PS1-7

Is the following reaction balanced?
NaHCO₃ --> Na₂CO₃ + H₂O + CO₂

• yes

• no

Tags

NGSS.HS-PS1-7

Which of the following models best demonstrates a balanced chemical equation?

• F

• G

• H

• J

Tags

NGSS.HS-PS1-7

aCaO (s) + b H₂O (l) ----------> cC

• a=1, b=1, c=1, C=Ca(OH)₂

• a=1, b=2, c=1, C=Ca(OH)₂

• a=1, b=1, c=1, C=CaOH₂

• a=2, b=1, c=2, C=Ca(OH)₂

Answer explanation

This is also called as Combination Reaction where single product is formed from two or more reactants.

CaO (s) + H₂O (l) ----------> Ca(OH)₂ (aq)

CaO - QuickLime

Ca(OH)₂ - Slacked Lime

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-7