Balancing a Chemical Equation

Q.

How to balance the chemical equation $\mathrm{Na}+{\mathrm{O}}_2\to {\mathrm{Na}}_2\mathrm{O}.$

Q. Representation of a chemical reaction using the names of the reactants and products is called ____.

1. Skeletal equation
2. Balanced chemical reaction
3. Unbalanced chemical reaction
4. Word equation

Q.

Balance the following equations.
$\mathrm{HgO}\to \mathrm{Hg}+{\mathrm{O}}_2$

Q.

Oil and fat-containing food items are flushed with nitrogen. Why?

Q.

Name the phenomenon due to which the taste and smell of oil food change when kept for a long time in the open. Suggest one method to prevent it.

Q.

Rancidity of fats occurs due to the exposure of fat to ___________ and_________.

Q.

Write a balanced equation for ${\mathrm{BCl}}_3\left(\mathrm{g}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)\to {\mathrm{H}}_3{\mathrm{BO}}_3\left(\mathrm{s}\right)+\mathrm{HCl}\left(\mathrm{g}\right)$.

Q.

A chemical equation is the shorthand form of representing a chemical reaction using the _______________(names/symbols or formulae) of the reactants and products.

Q.

In a chemical equation, the symbol _____ indicates to produce.

Q.

Can the formulae of the reactants and products be altered in balancing a chemical equation?

Q.

Balance the following chemical equations and identify the type of chemical reaction.

$\mathrm{Mg}\left(\mathrm{s}\right)+{\mathrm{Cl}}_2\left(\mathrm{g}\right)\to {\mathrm{MgCl}}_2\left(\mathrm{s}\right)$

Q. Oil and fat containing food items are flushed with nitrogen. Why?

Q.

Fill in the blanks:
________ causes corrosion of the marble or brick surface.

Q.

Give a reason why nitrogen is filled in food packets and not oxygen.

Q.

Complete and balance the equation

$\mathrm{CO}+{\mathrm{H}}_2\to$

Q.

Balance the following equations.
$\mathrm{Fe}+{\mathrm{O}}_2\to {\mathrm{Fe}}_2{\mathrm{O}}_3$

Q.

Which among the following is written on the LHS of a chemical equation?

1. Product

2. Heat released

3. Reactant

4. Catalyst

Q. [TBQ.VI.4]
State two conditions necessary for rusting of iron.

Q.

Balance the following chemical equation and identify the type of chemical reaction.

$\underset{\mathrm{sodium}}{\mathrm{Na}\left(\mathrm{s}\right)}+\underset{\mathrm{sulphur}}{\mathrm{S}\left(\mathrm{s}\right)}\stackrel{\mathrm{Fuse}}{\to }\underset{\mathrm{sodium}\mathrm{sulphide}}{{\mathrm{Na}}_2\mathrm{S}\left(\mathrm{s}\right)}$

Q. $H_2\left(g\right)+V_2{O}_5\left(s\right)\to V_2{O}_3\left(s\right)+H_{2}O\left(l\right)$
Let the coefficients for the given reaction be as follows:
$w{H}_2\left(g\right)+x{V}_2{O}_5\left(s\right)\to y{V}_2{O}_3\left(s\right)+z{H}_{2}O\left(l\right)$
What will be the values of w, x, y and z so that the reaction is balanced?

1. w = z, x = y, 5x = 3y + z
2. 2w = 2z, 2x = 2z, 2y = z
3. w = z, x = 2y, 5x = 3y + z
4. w = 2z, x = y, 5x = 3y + z

Q. Balanced chemical equations are equations in which the number of each type of atoms on the reactant side may or may not be equal to the number of respective atoms on the product side.

1. True
2. False

Q.

Balance the chemical equation ${\mathrm{N}}_2+{\mathrm{H}}_2\to {\mathrm{NH}}_3$

Q. Analyse the reaction given below:

${\text{CaCO}}_3\text{(aq)}$ + ${\text{H}}_2\text{O}\text{(aq)}$ + ${\text{CO}}_2\text{(g)}$ $\to$ ${\text{Ca(HCO}}_3{)}_2\text{(aq)}$

If X is the total number of oxygen atoms and Y is the total number of carbon atoms present in the chemical reaction after balancing, then determine X + Y.

1. 9
2. 16
3. 12
4. 8

Q. Estimate the value $x$ to balance the given equation.

$M{g}_3{N}_2\left(aq\right)+x{H}_{2}O\left(l\right)\to 3Mg\left(OH{)}_2\right(aq)+2N{H}_3(g)$

1. 4
2. 8
3. 6
4. 2

Q. The valency of calcium in calcium hydroxide is ____.

1. 1
2. 2
3. -1
4. -2

Q. What will be the values of the coefficients x, y and z if the given reaction is balanced?

${\text{xFeCl}}_3+\text{yMgO}\to {\text{Fe}}_{\text{2}}{\text{O}}_3+{\text{zMgCl}}_2$

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

Q.

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

1. NaOH (aq) + HCl (l) → NaCl (aq) + $H_{2}O$ (l)

2. NaOH (aq) + HCl (l) → NaCl (aq) + $H_{2}O$ (aq)

3. NaOH (aq) + HCl (aq) → NaCl (aq) + $H_{2}O$ (aq)

4. NaOH (aq) + HCl (aq) → NaCl (aq) + $H_{2}O$ (l)

Q. The balanced chemical equation for potassium reacting with water is:

1. $\text{K}\text{(s)}+2{\text{H}}_2\text{O(l)}\to \text{KOH(aq)}+{\text{H}}_2\text{(g)}$
2. $2\text{K}\text{(s)}+{\text{H}}_2\text{O(l)}\to 2\text{KOH(aq)}+{\text{H}}_2\text{(g)}$
3. $\text{K}\text{(s)}+{\text{H}}_2\text{O}\text{(l)}\to \text{KOH(aq)}+{\text{H}}_2\text{(g)}$
4. $2\text{K}\text{(s)}+2{\text{H}}_2\text{O}\text{(l)}\to 2\text{KOH(aq)}+{\text{H}}_2\text{(g)}$