Types of Chemical Reaction

Q. Question 2

Give an example of a double displacement reaction other than the one given in Activity 1.10.

Q.

In a double displacement reaction, are exchanged between the reactants.

1. atoms
2. ions
3. compounds

Q.

Passing ${\mathrm{H}}_2\mathrm{S}$ gas into a mixture of ${\mathrm{Mn}}^{2+},{\mathrm{Ni}}^{2+},{\mathrm{Cu}}^{2+}\mathrm{and}{\mathrm{Hg}}^{2+}$ ions in an acidified aqueous solution precipitates?

Q.

What do you understand by hydrolysis? Explain giving examples.

Q. A substance is said to be oxidised if it loses and gains .

1. oxygen
2. water
3. hydrogen
4. stability

Q.

What is a precipitation reaction?

Q. In a displacement reaction, which of the following metals will displace Nickel from its salt?

1. Magnesium
2. Tin
3. Lead
4. Copper

Q.

An oxidizing agent is a substance which:

A = Loses oxygen

B = Gains hydrogen

C = Gains oxygen

1. Only A

2. Only B

3. Only C

4. A and B

5. B and C

6. A and C

Q. Question 18
Which of the following are combination reactions?

(i) $2{\text{KClO}}_3\stackrel{\text{Heat}}{\to }2\text{KCl}+3{\text{O}}_2$
(ii) $\text{MgO}+{\text{H}}_2\text{O}\to {\text{Mg(OH)}}_2$
(iii) $4\text{Al}+3{\text{O}}_2\to 2{\text{Al}}_2{\text{O}}_3$
(iv) $\text{Zn}+{\text{FeSO}}_4\to {\text{ZnSO}}_4+\text{Fe}$

(a) (i) and (iii)
(b) (iii) and (iv)
(c) (ii) and (iv)
(d) (ii) and (iii)

Q.

The products obtained due to the reaction between K₂SO₄ and Cu(NO₃) are ________ and __________.

Q.

Which of the following is a combination reaction ?

1. $C\left(s\right)+O_2\left(g\right)⟶C{O}_2\left(g\right)$

2. $H_2{O}_2⟶H_2+O_2$

3. None of these

4. $Zn\left(s\right)+HgO\left(s\right)⟶ZnO\left(s\right)+Hg\left(l\right)$

Q.

In the reaction, H₂S + Cl₂ → 2HCl + S; hydrogen sulphide is:

1. Substance oxidized and oxidizing agent

2. Substance reduced and oxidizing agent

3. Substance oxidized and reducing agent

4. Substance reduced and reducing agent

Q. $F{e}_2{O}_3\left(s\right)+3C\left(s\right)\to 4\mathrm{Fe}\left(s\right)+3{\mathrm{CO}}_2\left(s\right)$
The oxidising agent in the given reaction is.

1. $F{e}_2{O}_3$
2. ${\mathrm{CO}}_2$
3. Fe

Q.

A carbonate which does not decomposes on heating

Q.

Give me any 10 Examples for the following reactions

1Chemical combination

2 Chemical composition

3 Chemical displacement

4 Chemical double displacement or exchange

Q.

Match the following reactions:-

$\begin{array}{cccc}& \text{Reaction Names}& & \text{Reactions}\\ \text{i}& \text{Displacement reaction}& & {\text{A. CaO + O}}_2\to {\text{2Ca(OH)}}_2\\ \text{ii}& \text{Decomposition Reaction}& & {\text{B. Fe + Pb(NO}}_3{)}_2\to {\text{Fe(NO\_3)}}_2\text{+ Pb}\\ \text{iii}& \text{Redox Reaction}& & {\text{C. MgCl}}_2{\text{+ Ca(OH)}}_2\to {\text{Mg(OH)}}_2{\text{+ CaCl}}_2\\ \text{iv}& \text{Combination Reaction}& & {\text{D. KClO}}_3\to {\text{2KCl + 3O}}_2\\ \text{v}& \text{Double Displacement Reaction}& & {\text{E. CO}}_2{\text{+ H}}_2\to {\text{2CO + H}}_2\text{O}\end{array}$

1. i - B, ii - D, iii - E, iv - A and v - C

2. i - B, ii - E, iii - D, iv - A and v - C

3. i - A, ii - E, iii - F, iv - B and v - C

4. i - A, ii - F, iii - E, iv - B and v - C

Q. Why are decomposition reactions called the opposite of combination reactions? Write equations for decomposition reactions.

[3 Marks]

Q.

Which of the following elements is not present in the reactivity series of metals?

1. Copper
2. Zinc
3. Hydrogen
4. Sulphur

Q. Indicate which of the substance/ion in the following reactions is an oxidising agent and which is a reducing agent?
$S{O}_2+2H_{2}S\to 3S+2H_{2}O$.

Q.

Classify each of the following reactions as combination, decomposition, displacement or double displacement reaction. [5 MARKS]

1. ${\text{H}}_2+{\text{Cl}}_2\to 2\text{HCl}$
2. $2{\text{KClO}}_3\to 2\text{KCl}+3{\text{O}}_2$
3. $\text{Zn}+{\text{CuSO}}_4\to {\text{ZnSO}}_4+\text{Cu}$
4. $2{\text{Pb(NO}}_3{)}_2\to 2\text{PbO(s)}+4{\text{NO}}_2+{\text{O}}_2$
5. $\text{NaOH}+\text{HCl}\to \text{NaCl}+{\text{H}}_2\text{O}$

Q.

What does Oxidizing agent mean?

Q.

Name the type of reactions represented below:

$\mathrm{XY}+\mathrm{WZ}\to \mathrm{XZ}+\mathrm{WY}$

Q.

Refer the given passage and answer the following questions.
Strength of an acid solution or a basic solution can be determined by knowing the hydrogen ion concentrations in them, using a pH scale.
(i) Neutral solution has pH 7.
(ii) Acidic solution has pH less than 7.
(iii) Basic solution has pH more than 7.
The pH of a solution is inversely proportional to the hydrogen(H+) ion concentration in it.

Teacher told three students Renuka, Bhawna, and Seema to test their saliva with pH paper before and after having their lunch. Seema observed that pH paper turned yellow and recorded pH value of 5.6 -5.8 after having lunch.

If this is true enter 1 else enter 0.

1. 1
2. 0

Q. Which of the following is an example of double displacement reaction?
(i) $C{O}_2\left(g\right)+H_2\left(g\right)\to CO\left(g\right)+H_{2}O\left(g\right)$
(ii) $P_4{O}_{10}\left(s\right)+6H_{2}O\left(l\right)\to 4H_{3}P{O}_4\left(aq\right)$​​​​​​​
(iii) $H_2+O_2\to H_{2}O$​​​​​​​
(iv) $CoC{l}_2\left(aq\right)+N{a}_{2}C{O}_3\left(aq\right)\to CoC{O}_3\left(aq\right)+2NaCl\left(aq\right)$​​​​​​​

1. (i)
2. (ii)
3. (iii)
4. (iv)

Q.

During An Exothermic Reaction

Q.

Q. Strength of an acid solution or a basic solution can be determined by knowing the hydrogen ion concentrations in them, using a pH scale.
(i) Neutral solution has pH 7.
(ii) Acidic solution has pH less than 7.
(iii) Basic solution has pH more than 7.
The pH of a solution is inversely proportional to hydrogen(H+) ion concentration in it.

1. Bhawna observed that pH paper turned red and recorded pH value of 2.3-2.5 after having lunch
2. Seema observed that pH paper turned yellow and recorded pH value of 5.6 - 5.8 before having lunch
3. Renuka observed that pH paper turned green and recorded pH value of 7.4- 7.9 before having lunch
4. Observations made by both Renuka and Seema were correct

Q.

Why is double displacement reaction so named?

Q. $AgN{O}_{3\left(aq\right)}+NaC{l}_{\left(aq\right)}\to AgC{l}_{\left(s\right)}+NaN{O}_{3\left(aq\right)}$.
Above reaction is a:

1. Precipitation reaction
2. Double displacement reaction
3. (a) and (b) both
4. Combination reaction

Q. Melting of ice is a physical change.

1. False
2. True