wayground logo

Free Printable Worksheets

Font size

S
M
L
XL
Worksheets

Chemical Reactions And Equations_LS_15_2

Total questions: 50

Worksheet time: 25mins

Name
Class
Date
1.

Zinc oxide reacts with carbon, on heating, to form zinc metal and carbon monoxide. Write a balanced chemical equation for this reaction.

a)

ZnO + C +Heat

→ Zn + CO

b)

ZnO(s)​​+2NaOH(aq.)​​→Na2​ZnO2(aq.)​​+H2​O(l)​

c)

2HCl+ZnO→ZnCl2​+H2​O

d)

Zn + CuO → ZnO + Cu

2.

Zinc oxide reacts with carbon, on heating, to form zinc metal and carbon monoxide. Name (i) oxidising agent,

ZnO(s)+C(s)+Heat⟶Zn(g)+CO(g)

a)

Zinc oxide.

b)

Hydrogen peroxide

c)

Potassium dichromate

d)

Sodium or calcium hypochlorite

3.

Zinc oxide reacts with carbon, on heating, to form zinc metal and carbon monoxide. Name (ii) reducing agent, in this reaction.

ZnO(s)+C(s)+Heat⟶Zn(g)+CO(g)

a)

Carbon.

b)

Glucose.

c)

Sodium sulfite.

d)

Sodium thiosulfate

4.

A chemical change in which two substances react to form a new substance is a ____________________________.

a)

decomposition reaction

b)

Combination reaction

c)

precipitation reaction

d)

combustion reaction

5.

2 Cu (s) + O2 (g) ---> 2 CuO (s)

a)

Combustion

b)

single replacement

c)

double replacement

d)

decomposition

e)

Combination

6.

CuO+H2​⟶Cu+H2​O 

a)

Combustion

b)

single displacement

c)

double displacement

d)

decomposition

e)

Combination

7.

Those reactions in which one element takes the place of another element in a compound, are known as _______ .

Equation: CuSO4 (aq)+ Zn (s)—–>ZnSO4+ Cu

a)

Combustion

b)

single displacement

c)

double displacement

d)

decomposition

e)

Combination

8.

Those reactions in which two compounds react by an exchange of ions to form two new compounds are called ________ reactions.

Equation: AgNO3 (aq) + NaCl (aq)—–>AgCl (s)+ NaNO3 (aq)

a)

Combustion

b)

Single displacement

c)

Double displacement

d)

Decomposition

e)

Combination

9.

Any reaction in which an insoluble solid (called precipitate) is formed that separates from the solution is called a _______

a)

Combustion

b)

Displacement

c)

Decomposition

d)

Combination

e)

Precipitation

10.

BaCl2​(aq)+ Na2​SO4​(aq) → BaSO4​(s) + 2NaCl(​aq)

Barium sulphate is insoluble in water and will precipitate as a white solid.

This reaction is an example of a ________ reaction.

a)

Combustion

b)

Single displacement

c)

Double displacement

d)

Decomposition

e)

Combination

11.

Barium chloride on reacting with sodium sulphate forms barium sulphate and sodium chloride.

BaCl2​(aq)+ Na2​SO4​(aq) → BaSO4​(s) + 2NaCl(​aq)

Type of reaction:

a)

Combustion

b)

Single displacement

c)

Double displacement

d)

Decomposition

e)

Combination

12.

(a)   is the gain of oxygen atoms.

13.

(a)   is the loss of oxygen atoms.

14.

Is this an oxidation or reduction reaction?

carbon + oxygen carbon dioxide

a)

Oxidation

b)

Reduction

15.

Is this an oxidation or reduction reaction?

water hydrogen + oxygen

a)

Oxidation

b)

Reduction

16.

Which of these metals do not form an ore?

a)

Copper

b)

Gold

c)

Iron

d)

Magnesium

17.

Which element has been oxidised?

iron oxide + lithium iron + lithium oxide

a)

iron

b)

lithium

c)

oxide

d)

lithium oxide

18.

Which element has been reduced?

iron oxide + lithium iron + lithium oxide

a)

iron

b)

lithium

c)

oxide

d)

iron oxide

19.

Balance the following displacement reaction.


Li2O + (a)   K K2O + 2Li

20.

Define the following in terms of gain or loss of hydrogen with one example each :(i) oxidation. What is the first statement of the audio clip?

a)

Oxidation is the gain of oxygen.

b)

Oxidation is the loss of hydrogen.

c)

Oxidation is loss of electrons

d)

Remember the acronym OIL which means oxidation is loss.

21.

Define the following in terms of gain or loss of hydrogen with one example each :(i) oxidation. What is the second statement of the audio clip?

a)

Oxidation is the gain of oxygen.

b)

Oxidation is the loss of hydrogen.

c)

Oxidation is loss of electrons

d)

Remember the acronym OIL which means oxidation is loss.

22.

Define the following in terms of gain or loss of hydrogen with one example each :(i) oxidation. What is the third statement of the audio clip?

a)

Oxidation is the gain of oxygen.

b)

Oxidation is the loss of hydrogen.

c)

Oxidation is loss of electrons

d)

Remember the acronym OIL which means oxidation is loss.

23.

Define the following in terms of gain or loss of hydrogen with one example each :(i) oxidation. What is the fourth statement of the audio clip?

a)

Oxidation is the gain of oxygen.

b)

Oxidation is the loss of hydrogen.

c)

Oxidation is loss of electrons

d)

Remember the acronym OIL which means oxidation is loss.

24.

In the reaction of formation of magnesium oxide magnesium undergoes ________

2Mg + O2 → 2MgO

a)

a) reduction

b)

b) oxidation

c)

c) hydrogenation

d)

d) decomposition

25.

(a) Define the following in terms of gain or loss of hydrogen with one example each : (ii) reduction

What is the first statement of the audio clip?

a)

Reduction reactions involve: 

Addition of hydrogen:

b)

Addition of electropositive element:

c)

Removal of oxygen

d)

Removal of electronegative element

e)

Reducing agent is a substance which brings about reduction.

26.

(a) Define the following in terms of gain or loss of hydrogen with one example each : (ii) reduction

What is the second statement of the audio clip?

a)

A very clever mnemonic to remember this concept is RIG (Reduction is gain)

b)

Addition of electropositive element:

c)

Removal of oxygen

d)

Removal of electronegative element

e)

Reducing agent is a substance which brings about reduction.

27.

(a) Define the following in terms of gain or loss of hydrogen with one example each : (ii) reduction

What is the third statement of the audio clip?

a)

A very clever mnemonic to remember this concept is RIG (Reduction is gain)

b)

Addition of electropositive element:

c)

Removal of oxygen

d)

Removal of electronegative element

e)

Reducing agent is a substance which brings about reduction.

28.

(a) Define the following in terms of gain or loss of hydrogen with one example each : (ii) reduction

What is the fourth statement of the audio clip?

a)

A very clever mnemonic to remember this concept is RIG (Reduction is gain)

b)

Addition of electropositive element:

c)

Removal of oxygen

d)

Removal of electronegative element

e)

Reducing agent is a substance which brings about reduction.

29.

(a) Define the following in terms of gain or loss of hydrogen with one example each : (ii) reduction

What is the fifth statement of the audio clip?

a)

A very clever mnemonic to remember this concept is RIG (Reduction is gain)

b)

Addition of electropositive element:

c)

Removal of oxygen

d)

Removal of electronegative element

e)

Reducing agent is a substance which brings about reduction.

30.

(a) Define the following in terms of gain or loss of hydrogen with one example each : (ii) reduction

What is the sixth statement of the audio clip?

a)

A very clever mnemonic to remember this concept is RIG (Reduction is gain)

b)

Addition of electropositive element:

c)

Removal of oxygen

d)

Removal of electronegative element

e)

Reducing agent is a substance which brings about reduction.

31.

Redox reactions are oxidation-reduction chemical reactions.

a)

A. TRUE

b)

B. FALSE

c)

C. Can be true or false

d)

D. Can not say

32.

All the redox reactions can be broken down into _________ different processes

a)

4

b)

3

c)

2

d)

1

33.

The substance getting reduced in a chemical reaction is known as the ?

a)

A. reducing agent

b)

B. oxidizing agent

c)

C. redox agent

d)

D. None of the above

34.

Fe2O3 + 3CO → 2Fe + 3 CO2

Is what kind of reaction?

a)

The iron oxide undergoes reduction (loses oxygen) to form iron. Therefore it is a reduction reaction

b)

while the carbon monoxide is oxidized (gains oxygen) to form carbon dioxide. Therefore it is an oxidation reaction.

35.

Which kind of reaction involves the breakdown of a compound into different compounds?

a)

A. Combination Reaction

b)

B. Displacement Reaction

c)

C. Disproportionation Reactions

d)

D. Decomposition Reaction

36.

2 Fe + O2 → Fe2O3

a)

Oxidation

b)

Reduction

37.

C + O2 → CO2      

a)

Oxidation

b)

Reduction

38.

Fe + S → FeS    

Addition of an electronegative element

a)

Oxidation

b)

Reduction

39.

Removal of an electropositive element

2 KI + H2O2 → I2 + 2 KOH      

a)

Oxidation

b)

Reduction

40.

Addition of hydrogen

N2 + 3 H2 → 2 NH3

a)

Oxidation

b)

Reduction

41.

Removal of oxygen

ZnO + C → Zn + CO  

a)

Oxidation

b)

Reduction

42.

H2S + Cl2 → 2HCl + S

Element Sulphur has undergone?

a)

Oxidation

b)

Reduction

c)

Redox

43.

H2S + Cl2 → 2HCl + S

Element Chlorine has undergone?

a)

Oxidation

b)

Reduction

c)

Redox

44.

H2S + Cl2 → 2HCl + S

This is a ______ reaction

a)

Oxidation

b)

Reduction

c)

Redox

45.

CuO + H2 → Cu +H2O

In CuO to Cu since Oxygen is getting removed; therefore Copper is undergoing ______

a)

Oxidation

b)

Reduction

c)

Redox

46.

CuO + H2 → Cu +H2O

H2 is undergoing _______; to become H2O.

a)

Oxidation

b)

Reduction

c)

Redox

47.

CuO + H2 → Cu +H2O

This is a _______ reaction

a)

Oxidation

b)

Reduction

c)

Redox

48.

MnO4-+ I- → MnO2 + I2

Here I- is undergoing _____ to I2

a)

Oxidation

b)

Reduction

c)

Redox

49.

MnO4-+ I- → MnO2 + I2

Here MnO4 - is undergoing _______ to MnO2.

a)

Oxidation

b)

Reduction

c)

Redox

50.

MnO4-+ I- → MnO2 + I2

This is ia ______ reaction

a)

Oxidation

b)

Reduction

c)

Redox