PROBLEM SOLVING USING CHEMICAL EQUATIONSMohamad Shahir Bin Ismail

AT THE END OF THIS LESSON, STUDENTS SHOULD BE ABLE TO:-

Solve numerical problems using chemical equations.

A chemical reaction can be represented by a chemical equation, which may be in word form or symbol form.Example:-

CHEMICAL EQUATION TELL US SUBSTANCES REACT TOGETHER IN A REACTION AND WHAT IS PRODUCED

THE COEFFICIENTS OF A BALANCED EQUATION TELL US THE MOLE RATIO OF THE REACTANTS AND PRODUCTS . WE CAN USE THE MOLE RATIO TO CALCULATE THE AMOUNT OF PRODUCT IN A REACTION. WE CAN ALSO USE IT TOO CALCULATE THE AMOUNT OF REACTANTS TO PRODUCE A CERTAIN AMOUNT OF PRODUCTS.

Example 1.

STEP 1: WRITE THE BALANCE EQUATION OF THE REACTION:-

Word Equation

Symbol Equation

Unbalanced Equation

Balanced Equation

STEP 2: COMPARE THE MOLE RATIO:-

From the balanced equation above we know that: 1 mole of Copper metal 2 mole of silver.

STEP 3: IDENTIFY THE INFORMATION GIVEN AND WHAT YOU WANT TO FIND?.

We want to know how many moles of silver would produced if 0.25 mole of copper is consumed…

From the balanced equation above we know that: 1 mole of Copper metal 2 mole of silver.

0.25 mole of Copper metal how many mole of silver

STEP 4: CALCULATE THE NUMBER OF MOLE