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Lec : Balancing Chemical Equations. NaOH + HCl NaCl + H 2 O When balancing a chemical equation the quantity and types of elements in the reactants has to be equal to the quantity and types of elements in the products.
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NaOH + HClNaCl + H2OWhen balancing a chemical equation the quantity and types of elements in the reactants has to be equal to the quantity and types of elements in the products.
NaOH + HClNaCl + H2OStep 1. Break the reactants and products down into the type of elements.Na NaO OH HCl Cl
NaOH + HClNaCl + H2OStep 2. Place the quantity of each element in the reactants and products.Na:1 Na:1O:1 O:1H:2 H:2Cl:1 Cl:1
NaOH + HClNaCl + H2OStep 3. If the quantity of each element in the reactants and products is not equal, multiply each side of the equation by a number that makes them equal. Place the number in front of the compound that contains that element that you want to balance.This will cause the other elements in the compound to increase also. Na:1 Na:1O:1 O:1H:2 H:2Cl:1 Cl:1
Fe(s)+ 3O22Fe2O3Step 3:(reactants) (products)Fe: 1 Fe: 2O: 2 x 3 = 6 O: 3 x 2 = 6
Fe(s)+ 3O22Fe2O3Step 3:The increase in O on the product side causes the Fe to increase too and now needs to be increased.(reactants) (products)Fe: 1 Fe 2 x 2 = 4O: 2 x 3 = 6 O: 3 x 2 = 6
4 Fe(s)+ 3 O22 Fe2O3Step 3: Now you need to balance the Fe on the reactant side.(reactants) (products)Fe 1 x 4 = 4 Fe 2 x 2 = 4O 2 x 3 = 6 O 3 x 2 = 6
4 Fe(s)+ 3 O22 Fe2O3 What does this chemical reaction make?
4 Fe(s)+ 3 O22 Fe2O3 What does this chemical reaction make? Answer: Rust!
Balancing a chemical equation with a Chemical GroupPb(NO3)2 + KI PbI2+ KNO3
Balancing a chemical equation with a Chemical GroupPb(NO3)2 + KI PbI2+ KNO3NO3 is a chemical group on both sides of the chemical equations.
Balancing an chemical equation with a Chemical Group Pb(NO3)2 + KI PbI2+ KNO3Step 1Pb: Pb: NO3: NO3 :K: K :I: I:
Balancing an chemical equation with a Chemical Group Pb(NO3)2 + KI PbI2+ KNO3Step 2Pb: 1 Pb :1NO3: 2 NO3 :1K: 1 K :1 I: 1 I: 2
Balancing an chemical equation with a Chemical Group Pb(NO3)2 + KI PbI2+ 2KNO3Step 3: Balance the chemical group first.Pb: 1 Pb :1NO3: 2 NO3 :1 x 2 =2K: 1 K :1 I: 1 I: 2
Balancing an chemical equation with a Chemical Group Pb(NO3)2 + 2KI PbI2+ 2KNO3Step 3Pb: 1 Pb :1NO3: 2 NO3 :1 x 2 = 2K: 1 x 2 = 2 K :1 x 2= 2I: 1 I: 2
Balancing an chemical equation with a Chemical Group Pb(NO3)2 + 2KI PbI2+ 2KNO3Step 3Pb: 1 Pb :1NO3: 2 NO3 :1 x 2 =2K: 1 x 2 = 2 K :1 x 2= 2 I: 1 x 2 = 2 I: 2