Writing Chemical Equations

Q.

What is chemical equation

Q.

Represent the following reaction in the form of a chemical equation.
Iron reacts with copper sulphate solution to produce copper and ferrous sulphate. Copper separates out of the solution while ferrous sulphate remains in solution.

1. $Fe\left(s\right)+CoS{O}_4\left(aq\right)\to Co\left(aq\right)+FeS{O}_4\left(aq\right)$

2. $Fe\left(s\right)+CuS{O}_4\left(aq\right)\to Cu\left(s\right)+FeS{O}_4\left(aq\right)$

3. $Fe\left(s\right)+CoS{O}_4\to Co\left(s\right)+FeS{O}_4\left(aq\right)$

4. $Fe\left(s\right)+CuS{O}_4\left(l\right)\to Cu\left(s\right)+FeS{O}_4\left(l\right)$

Q.

Which has maximum no. of molecules among the following and why?

1. $44\mathrm{g}$ of ${\mathrm{CO}}_2$

2. $48\mathrm{g}$of ${\mathrm{O}}_2$

3. $8\mathrm{g}\mathrm{of}{\mathrm{H}}_2$

4. $64\mathrm{g}\mathrm{of}{\mathrm{SO}}_2$

Q.

How to write chemical reaction

Q.

Differentiate between combination and decomposition reaction.

Q.

What is the correct chemical equation for combustion of Zn?

1. $3Zn+N_2\to Z{n}_3{N}_2$
2. $2Zn+O_2\to 2ZnO$
3. $Zn+CuS{O}_4\to ZnS{O}_4+Cu$
4. $2Zn+4H_{2}O\to 2Zn(OH{)}_2+4H_2$

Q. Match the given physical states to the correct symbols as used in chemical equations.

Physical state	Symbol
1. Aqueous	(A) (l)
2. Concentrated	(B) (dil.)
3. Dilute	(C) (aq)
4. Liquid	(D) (aqu)
	(E) (conc.)
	(F) (con)

1. 1 - D
   2 - F
   3 - B
   4 - A
2. 1 - D
   2 - E
   3 - B
   4 - A
3. 1 - C
   2 - F
   3 - B
   4 - A
4. 1 - C
   2 - E
   3 - B
   4 - A

Q.

$2H_2+O_2\to 2H_{2}O$

What can be infered from the above equation?

1. All of these.

2. 2 molecules of hydrogen combines with 1 molecule of oxygen to form 2 molecules of water.

3. 4 u of hydrogen molecules combine with 32 u of oxygen molecule to form 36 u of water molecules.

4. 2 moles of hydrogen combines with 1 mole of oxygen to form 2 moles of water.

Q.

An unbalanced equation is known as a ___ equation.

Q.

The substances that undergo chemical changes and are represented on the left side of the arrow in a chemical reaction are called ___ .

Q. Q1. What is chemical equation

Q.

Which of these is not a type of chemical reaction?

1. Conduction reaction

2. Combination reaction

3. Decomposition reaction

4. Displacement reaction

Q.

Write skeletal equations for the following word equations.

$\mathrm{Hydrogen}+\mathrm{Chlorine}\to \mathrm{Hydrogen}\mathrm{chloride}$

Q. Carbon in wood reacts with oxygen in the air to give carbon dioxide gas.
Which among the following is the correct representation of this chemical reaction?

1. $\text{C(g)}+{\text{O}}_2\text{(g)}\to {\text{CO}}_2\text{(g)}$
2. $\text{C(s)}+{\text{O}}_2\text{(g)}\to {\text{CO}}_2\text{(g)}$
3. $\text{C(s)}+2\text{O(g)}\to {\text{CO}}_2\text{(g)}$
4. $\text{C(g)}+2\text{O(g)}\to {\text{CO}}_2\text{(g)}$

Q.

Match the following.

Relate physical states used in chemical reactions to their symbols.

$\begin{array}{cc}\text{Physical State}& \text{Symbol}\\ \text{1. Gas}& \left(A\right)\left(dw\right)\\ \text{2. Solid}& \left(B\right)\left(g\right)\\ \text{3. Liquid}& \left(C\right)\left(aq\right)\\ \text{4. Dissolved in water (solution with water)}& \left(D\right)\left(l\right)\\ & \left(E\right)\left(s\right)\\ & \left(F\right)\left(v\right)\end{array}$

1. E, B, C, D

2. B, D, E, C

3. C, D, E, B

4. B, E, D, C

Q.

Which of the following is/are correct regarding a chemical reaction?

1. New substances are formed.

2. Chemical properties change.

3. One substance reacts with another and undergoes a change in chemical composition.

4. Physical properties may change.

Q.

The sign $\downarrow$ indicates:

1. release of gas

2. dissolution of gas

3. formation of a precipitate

4. lowering of temperature

Q.

To make the chemical reaction more informative, ___________ of reactant & product are mentioned.

1. Chemical name
2. Chemical formulae
3. Physical state
4. Chemical equation

Q.

Ravi conducted an experiment, he added dil.hydrochloric acid to zinc granules in a conical flask. Zinc chloride was formed and hydrogen was liberated. He represented the reaction in the following manner.

$ZnC{l}_2\left(l\right)+H_2\left(g\right)\to Zn\left(s\right)+2HCl\left(dil\right)$

Can we say the reaction above is in the correct representation?

1. False

2. True

Q. A first order reaction takes 20 minutes for 25% decomposition.calculate the time when 75% of the reaction will be completed.

Q.

Write the word equations for the following chemical equation.

$\mathrm{C}\left(\mathrm{s}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)\to {\mathrm{CO}}_2\left(\mathrm{g}\right)$

Q.

Write chemical equation in symbols and formulae for the following word equation.

$\mathrm{Magnesium}+\mathrm{Oxygen}\to \mathrm{Magnesium}\mathrm{oxide}$

Q.

$CaO\left(s\right)+H_{2}O\left(l\right)\to Ca\left(OH{)}_2\right(aq)+heat$

What can be inferred from the above reaction?

(i) $CaO$ is solid.

(ii) $CaO$ can react easily with water.

(iii) $H_{2}O$ is liquid.

(iv) $H_{2}O$ is in vapour state.

(v) $Ca(OH{)}_2$ forms a solution with water

1. (i), (iii), (iv), (vi)

2. (i), (ii), (iii), (v), (vi)

3. (ii), (iii), (v), (iv)

4. (v), (iv)

Q. Change of state is a characteristic of a chemical change only.

1. False
2. True

Q. How can a chemical equation be read?
Example,
How will I read👇
Zn+H2SO4 ➡ZnSO4+H2⬆

Q.

Which of the following is not a decomposition reaction?

1. CaCO₃ → CaO + CO₂

2. 2KClO₃ →2KCl + 3O₂

3. Digestion of food in the body.

4. H₂ + Cl₂ → 2HCl

Q. What is meant by chemical combination? Give an example.

Q.

alluminium + ferrous sulphate - alluminium sluplate and iron

Q. Where can I find the Brownian motion in the videos in the guided section of chemistry???

Q. Change of state is a characteristic of a chemical change only.

1. False
2. True