# NCERT solutions for class 10 science chapter 1

NCERT solutions for class 10: We have taken the topic of balancing the chemical equation of class 10th science and tried to make it simpler and easier for you.

We have solved the question of balancing equation for you. You can easily get solution of Chapter 1 science of class 10th NCERT. We tried to solve the NCERT textbook question of exercise of Chapter 1 science.

Hope this video will help you to understand the method of balancing equations and solve questions in exam easily.

We have got the solution of Chapter – 1 of class 10th science. Mostly we have covered the questions of balancing the equation in these slides and videos

Chemical reaction is a process in which two or more reactants/ substances react with each other to form a new product or substance

Changes observed during chemical reaction are

• Change in color
• Change in state
• Evolution of gas
• Change in temperature

And of course since it is a chemical reaction there will be certain changes in the chemical properties of substances.

## Chemical Equation

The method of writing the chain of reaction with the help of symbols and chemical formulas is known as chemical equation.

The left-hand side of the equation contains the reactants (substances that are reacting) and on the right-hand side is the product (the result of reaction)

It is very important for a chemical equation to be balanced. Balancing means having the same number of Atoms of an element on both sides of the equation.

## Questions on equation balancing

Let us now try some questions of balancing the equations:

This is simple mathematics of multiplication, division, addition and subtraction.

Step1: Check the elements or reactants involved on left hand side. In rough make two columns LHS and RHS

Step 2: Write the number of atoms involved of each element against them. So this separately for both the sides.

Step3: Now do simple calculations to check if both the sides are having same or different numbers for each element

Step4: Add and multiply wherever required.

Step 5: At last recheck and recalculate both the sides to confirm whether the equation is balanced or not.

Now let’s see solutions to NCERT questions and problems

## Write a balanced chemical equation for the following:

a.) Hydrogen + Chloride ——>Hydrogen Chloride

H2 + Cl2 → 2HCl

On L.H.S we have 2 atoms of hydrogen and 2 atoms of chloride.

On R.H.S we have one each. Hence we multiply R.H.S by 2.

b.) Barium Chloride + Aluminium Sulphate—-> Barium Sulphate + Aluminium Chloride3BaCl2 + Al2(SO4)3 → 2AlCl3 + 3BaSO4

c.) Sodium + Water —-> Sodium Hydroxide + Hydrogen

2Na + 2H2O → 2NaOH + H2

On LHS we have one  atom of Na, 2 atom of Hydrogen and 1 of oxygen

On RHS we have 1 atom of Na and O. 3 atoms of hydrogen.

To balance we multiplied Na and H2O by 2 and NaOH by 2 on RHS

## NCERT Solutions

5.  Translate the following statements into chemical equations and balance them. (NCERT solutions for class 10)

(a) Hydrogen gas combines with nitrogen to form ammonia.

H2 + N2 → NH3

Balanced: 3H2 + N2 → 2NH3

(b) Hydrogen sulphide gas burns in air to give water and sulphur dioxide.

H2S + O2 → H2O + SO2Balanced: 2H2S + 3O2 → 2H2O + 2SO2

(c) Barium chloride reacts with aluminium sulphate to give Aluminium chloride and a precipitate of barium sulphate.

BaCl2 + Al2(SO4)3 → AlCl3 + BaSO4

Balanced: 3BaCl2 + Al2(SO4)3 → 2AlCl3 + 3BaSO4

(d) Potassium metal reacts with water to give potassium hydroxide and Hydrogen gas.

Unbalanced: K + H2O → KOH + H2Balanced:  2K + 2H2O → 2KOH + H2

## Balance the following chemical equations.

(a) HNO3 + Ca(OH)2 → Ca(NO3)2 + H2O

2HNO3 + 2Ca(OH)2 → 2Ca(NO3)2 + 2H2O

(b) NaOH + H2SO4 → Na2SO4 + H2O

6NaOH + 3H2SO4 → H2SO4 + 6H2O

(c) NaCl + AgNO3 → AgCl + NaNO3

NaCl + AgNO3 → AgCl + NaNO3

(d) BaCl2 + H2SO4 → BaSO4 + HCl BaCl2 + H2SO4 → BaSO4 + 2HCl

#### Write the balanced chemical equation for the following reactions.

a) Calcium hydroxide + Carbon dioxide —-> Calcium carbonate + Water

2Ca(OH)2 + 2CO2 → 2CaCO3 + 2H2O

b) Zinc + Silver nitrate —-> Zinc nitrate + Silver

Zn + 2AgNO3 → Zn(NO3)2 + 2Ag

c) Aluminium + Copper chloride —-> Aluminium chloride + Copper

2Al + 3CuCl3 → 2AlCl3 + 3Cu

d) Barium chloride + Potassium sulphate —-> Barium sulphate + Potassium chlorideBaCl2 + K2SO4 → BaSO4 + 2KCl

### Write a balanced chemical equation for the following and identify the type of reaction of each case

i) KBr + BaI2 → KI + BaBr2

2KBr + BaI2 → 2KI + BaBr2 . This is Double Displacement Reaction.

ii) ZnCO3 → ZnO + CO2

ZnCO3 → ZnO + CO2. This is Decomposition Reaction.

iii) H2 + Cl → HCl

H2 + Cl → 2HCl. This is Combination Reaction.

iv) Mg + HCl → MgCl2 + H2Mg + 2HCl → MgCl2 + H2. This is Displacement Reaction.