Balancing of Chemical Equations

aCaCO₃ (s) ---------> bB + cC

• a=1, b=1, c=1, B=CaO, C=CO₂

• a=1, b=1, c=1, B=Ca₂O, C=CO₂

• a=1, b=1, c=1, B=CaO₂, C=CO₂

• a=2, b=1, c=2, B=CaO, C=CO₂

Answer explanation

This is also called as Decomposition Reaction. Single reactant breaks down to form simple products.

CaCO₃ also called as Lime stone when heated forms CaO (QuickLime) with release of Carbon Dioxide.

When Decomposition is carried by heating, it called as Thermal Decomposition.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

aPb(NO₃)₂ (s) ---------------> bB + cC + dD

• a = 1, b = 1, c= 4, d = 1, B = PbO, C = NO₂, D = O₂

• a = 2, b = 2, c= 4, d = 1, B = PbO, C = NO₂, D = O₂

• a = 2, b = 2, c= 4, d = 1, B = PbO, C = NO₃, D = O₂

• a = 2, b = 2, c= 4, d = 3, B = PbO, C = NO₃, D = O₂

Answer explanation

This reaction happens when Lead Nitrate is heated.

This is also called as Decomposition Reaction. Single reactant breaks down to form simple products.

When Decomposition is carried by heating, it called as Thermal Decomposition.

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-7

aAgCl (s) ------------> bB + cC

• a=2, b=2, B=Ag, c=1, C=Cl₂

• a=1, b=1, B=Ag, c=1, C=Cl

• a=2, b=2, B=Ag, c=1, C=CL₂

• a=1, b=1, B=Ag, c=1, C=CL

Answer explanation

This reaction is known as Decomposition Reaction.

White Silver Chloride turns grey in sunlight. This is due to decomposition of silver chloride into silver and chlorine by light.

2AgCl (s) ------------> 2Ag + Cl₂

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-7

aMg + bO₂ -----------> cC

• a = 1, b=1, c=1, C=MgO

• a = 1, b=1, c=1, C=Mg₂O

• a = 4, b=1, c=2, C=Mg₂O

• a = 2, b=1, c=2, C=MgO

Answer explanation

This process is known as Burning of Magnesium Ribbon.

2Mg + O₂ ------------> 2MgO

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Zn + H₂SO₄ ------------>

• a=2, b=2, c=2, C=ZnSO₃, d=2, D=H₂O

• a=2, b=1, c=1, C=ZnH₂ d=1, D=ZnSO₄

• a=1, b=1, c=1, C=ZnSO₄, d=1, D=H₂

• a=1, b=1, c=1, C=ZnH₂ d=1, D=ZnSO₄

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-7

Fe + H₂O ------------>

• a=3, b=3, c=1, C=Fe₃O₄, d=3, D=H₂

• a=3, b=4, c=1, C=Fe₃O₄, d=4, D=H₂

• a=4, b=6, c=2, C=Fe₂O₃, d=6, D=H₂

• a=4, b=6, c=1, C=Fe₂O₃, d=5, D=H₂

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

NGSS.HS-PS1-7

aFe (s) + bCuSO₄ (aq) -----------> cC + dD

• a=1, b=2, c=1, C=FeSO₄, d=2, D=Cu

• a=2, b=1, c=2, C=Fe(SO)₄, d=1, D=Cu

• a=1, b=1, c=1, C=FeSO₄, d=1, D=Cu

• a=1, b=1, c=2, C=FeSO₄, d=1, D=Cu

Answer explanation

This is known as Displacement Reactions.

Iron Nail becomes brownish in colour and blue colour of the copper sulphate solution fade.

In this reaction, iron has displaced or removed another element, copper, from copper sulphate solution.

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-7

Which equation is balanced?

• PbO₂ + 2H₂

• SO₂ + H₂0 --> H₂SO₄

• 2Na + 2H₂O --> 2NaOH + H₂

Tags

NGSS.HS-PS1-7

What law governs the balancing of chemical equations?

• Law of Energy

• Law of Conservation of Matter/Mass

• Law of Gravity

• Law of Matter Movement

Tags

NGSS.HS-PS1-7

What are the coefficients that would properly balance this equation? Ca + H2O --> Ca(OH)2 + H2

• 2,1 --> 2,1

• 1,2 --> 1,1

• 1,2 --> 2,4

• 1,2 --> 2,1

Tags

NGSS.HS-PS1-7