Steps for Balancing Chemical Equations

Q.

Hydrogen gas combines with nitrogen to form Ammonia. Translate the following statement into the chemical equation and then balance the equation?

Q.

In an experiment, Sodium hydroxide solution (in water) reacts with hydrochloric acid solution (in water) to produce Sodium Chloride solution and water. Which of the following correctly represents the balanced equation (with physical states) for this experiment?

1. 

2. 

3. 

4. 

Q.

Balance this equation ( I )Mgo+H2O=Mg(OH)2

Q.

Complete and balance the reaction: ${\mathrm{N}}_2+{\mathrm{O}}_2\to \mathrm{\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_}.$

Q.

How will you provide information regarding the reaction conditions in a chemical equation?

Q.

Which coloured entity can be changed to balance the chemical reaction?

1. Entities in green

2. Entities in red

3. Entities in both red and green

4. None of the colour

Q.

Find the value of a, b, c, and d in accordance with the law of conservation of mass for the reaction given below.
$aM{g}_3{N}_2\left(s\right)+b{H}_{2}O\left(l\right)\to cMg\left(OH{)}_2\right(s)+dN{H}_3(g)$

1. a, b, c and d are 1, 3, 4 and 2 respectively.
2. a, b, c and d are 1, 6, 2 and 3 respectively.
3. a, b, c and d are 2, 6, 3 and 2 respectively.
4. a, b, c and d are 1, 6, 3 and 2 respectively.

Q.

Complete the chemical equation and balance them.

${\mathrm{BaCl}}_2+\mathrm{\_\_\_\_\_\_\_\_}\to {\mathrm{BaSO}}_4+\mathrm{NaCl}$

Q.

The balancing of a compound is started with the element having the most number of atoms.

1. False

2. True

Q. Why does chemical equation need to be balanced?

Q.

Consider the steps for the balancing of a chemical reaction. Identify the correct sequence.

(a) Check the correctness of the balanced equation.

(b) Make the list of number of atoms of different elements present in the unbalanced equation.

(c) Draw the boxes around each chemical formula (for compound/ element).

(d) Choose and balance the second element and so on.

(e) Start balancing from the compound which has more number of atoms and balance the first element.

(f) Write the symbols of physical states for compounds/ elements.

1. e, d, a, f, b and c.

2. c, b, a, d, e and f

3. c, b, e, d, a, and f

4. e, d, b, a, f and c

Q.

Write the skeletal equation for the following word equation:

Lead nitrate $\to$Lead oxide + Nitrogen dioxide + Oxygen

Q. On balancing the given equation, a, b, c and d respectively would be $aF{e}_2{O}_3+b{H}_2\to cFe+d{H}_{2}O$

1. 1, 1, 2, 3
2. 1, 1, 1, 1
3. 1, 3, 2, 3
4. 1, 2, 2, 3

Q.

The physical state of salt that dissolves in water and forms solution is:

1. (aq)

2. (s)

3. (l)

4. (sol)

Q.

Find the value of y.

$3Fe+y{H}_{2}O\to F{e}_3{O}_4+4H_2$

1. 1

2. 3

3. 2

4. 4

Q. How to balance a chemical equation?

Q.

Identify the monoatomic and polyatomic ions from the following equation-
$Pb(N{O}_3{)}_2$ + $K_{2}S{O}_4$ $\to$ $2KN{O}_3$ + $PbS{O}_4$

1. Monoatomic ions- ${\mathrm{Pb}}^{+2}$, ${\mathrm{NO}}_3^{-}$
   Polyatomic ions- $K^{+}$, ${\mathrm{SO}}_4^{-2}$

2. Monoatomic ions- ${\mathrm{SO}}_4^{-2}$, ${\mathrm{NO}}_3^{-}$
   Polyatomic ions- $K^{+}$, ${\mathrm{Pb}}^{+2}$

3. Monoatomic ions- ${\mathrm{SO}}_4^{-2}$, $K^{+}$
   Polyatomic ions- ${\mathrm{NO}}_3^{-}$, ${\mathrm{Pb}}^{+2}$

4. Monoatomic ions- ${\mathrm{Pb}}^{+2}$, $K^{+}$
   Polyatomic ions- ${\mathrm{NO}}_3^{-}$, ${\mathrm{SO}}_4^{-2}$

Q.

$2Na+2H_{2}O\to xNaOH+H_2$

The value of x is:

1. 1

2. 2

3. 3

4. 4

Q.

Write the skeletal equation for the following word equation:

Nitrogen + Hydrogen $\to$Ammonia

Q. Balance the following equation, and hence choose the values of the coefficients w, x, y, z:
$F{e}_2{O}_3\left(s\right)+C\left(s\right)\to Fe\left(s\right)+C{O}_2\left(g\right)wF{e}_2{O}_3\left(s\right)+xC\left(s\right)\to yFe\left(s\right)+zC{O}_2\left(g\right)$

1. w = 3, x = 2, y = 4, z = 3
2. w = 3, x = 2, y = 4, z = 2
3. w = 3, x = 2, y = 3, z = 4
4. w = 2, x = 3, y = 4, z = 3

Q.

10. Arrange the following equations in the correct sequence to obtain a normal salt.

(1) Al(OH)Cl₂ + HCl → AlCl₃ + H₂O

(2) Al(OH)₃ + HCl → Al(OH)₂Cl + H₂O

(3) Al(OH)₂Cl + HCl → Al(OH)Cl₂ + H₂O

1. 321

2. 231

3. 123

4. 312

Q.

The variable coefficients d, e, f and g are considered for balancing the chemical equation. Relationships between these variable are constructed by balancing the atoms of each element on either side of the reaction. Which of the following are correct?

(Note: Coefficients should be natural numbers.)

(i) 2d= f, d = 3g and e= f + 2g

(ii) 2d = f, 3d = g and 2e = 2f + g

(iii) d = f2, 2d = g and e = 2f + 2g

(iv)d = 1, e = 3.5, f = 4 and g = 6

(v) d = 2, e = 7, f = 4 and g = 6

(vi) d = 2, e = 7, f = 3 and g = 4

1. (ii), (v)

2. (v), (iii)

3. (ii), (iv)

4. (vi), (i)

Q. (a) Potassium chlorate (KClO₃) on heating forms potassium chloride and oxygen. Write a balanced equation for this reaction and indicate the evolution of gas.
(b) Rewrite the following information in the form of a balanced chemical equation:
Magnesium burns in carbon dioxide to form magnesium oxide and carbon.

Q.

Balance the following equation, and hence choose the values of the coefficients v, w, x, y, z:

$yHCl\left(aq\right)+wMn{O}_2\left(s\right)\to xMnC{l}_2\left(aq\right)+yC{l}_2\left(g\right)+z{H}_{2}O\left(l\right)$

1. v = 4, w = 2, x = 1, y = 1, z = 2

2. v = 4, w = 2, x = 2, y = 1, z = 2

3. v = 4, w = 2, x = 2, y = 2, z = 2

4. v = 4, w = 0, x = 1, y = 1, z = 2

Q.

Who stated the Law of conservation of mass?

Q.

What will be A, B and C if the following reaction is balanced?

$AFeC{l}_3+BMgO\to F{e}_2{O}_3+CMgC{l}_2$

1. A = 2, B = 3, C = 3

2. A = 2, B = 4, C = 3

3. A = 3, B = 2, C = 2

4. A = 3, B = 2, C = 3

Q.

Fill in the blank with a number which balances the following reaction.

$3Fe+4H_{2}O\to F{e}_3{O}_4+y{H}_2$

Then, y = ___

Q.

Consider the following reaction.
$CaC{O}_3$ + $H_{2}O$ + $C{O}_2$ $\to$ $Ca(HC{O}_3{)}_2$

$\begin{array}{cc}\text{Element}& \text{Number of atoms present}\end{array}$
$\begin{array}{ccc}& \text{Reactant side}& \text{Product side}\\ \text{Calcium}& 1& 1\\ \text{Carbon}& 2& Y\\ \text{Oxygen}& X& 6\\ \text{Hydrogen}& 2& 2\end{array}$
Recognise $X$ and $Y$. The value of $X+Y$ is___.

Q.

Balance the following equation, and hence choose the values of the coefficients w, x, y, z:
$wF{e}_2{O}_3\left(s\right)+xC\left(s\right)\to yFe\left(s\right)+zC{O}_2\left(g\right)$

1. w = 3, x = 2, y = 4, z = 2

2. w = 3, x = 2, y = 3, z = 4

3. w = 2, x = 3, y = 4, z = 3

4. w = 3, x = 2, y = 4, z = 3

Q.

Which of the following law is obeyed during the balancing of a chemical equation?

1. Conservation of energy

2. Conservation of inertia

3. Periodic Law

4. Conservation of mass