Physical and Chemical Changes Test

Result

Physical and Chemical Changes Test - 9

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
1 / -0

Adding salt to water makes it salty. Which of the following is true regarding this change?

A
It is a chemical change because a new substance is formed

B
It is a physical change because the original substances can be recovered

C
It is a chemical change because there is exchange of heat

D
It is a physical change because there is a slight change in colour

Solution

Adding salt to water makes it salty. This is a physical change because the original substances can be recovered by evaporation. In a chemical change, substances cannot be recovered.
Question 2
1 / -0

The change given below is an example of :
$$\text{Hydrogen + Oxygen}$$ $$\longrightarrow$$ $$\text {Water}$$

A
Physical change

B
Chemical change

C
Both A and B

D
Neutralization reaction

Solution

Hydrogen and oxygen combine together to form water is a chemical change. When a new substance is formed the change is called a chemical change.
Question 3
1 / -0

Which of the following is true for ash, which is obtained by burning wood in the presence of oxygen?

A
The properties of ash will be similar to wood

B
The properties of ash will be similar to oxygen

C
The properties of ash will be different from both wood and oxygen

D
None of the above

Solution

The burning of wood in the presence of oxygen produces ash. In this example, wood and oxygen undergo a chemical change to produce ash. The properties of ash are very different from wood or oxygen. So, options A, B, and D are incorrect and, option C is correct.
Question 4
1 / -0

Which of the following is NOT a chemical change?

A
Digestion of food

B
Precipitation of rain and snow

C
Rusting of iron

D
Burning of paper

Solution

Precipitation is any product of the condensation of atmospheric water vapour that falls under gravity. The main forms of precipitation include drizzle, rain, sleet, and snow.

Precipitation occurs when a portion of the atmosphere becomes saturated with water vapour so that the water condenses and "precipitates". Here the water vapour in the air is changing from one form to another.

So precipitation of snow and rain is not a chemical change. In all the other options, a new substance is formed and the main substances cannot be reversed. So, they are chemical changes.
Question 5
1 / -0

Chemical changes are _____ .

A
temporary, reversible and a new substance is produced

B
always accompanied by exchange of light

C
permanent, irreversible and a new substance is produced

D
never accompanied by exchange of light and heat energy

Solution

Chemical changes take place on the molecular level. A chemical change produces a new substance. It is a permanent and irreversible change.
Examples of chemical changes include combustion (burning), cooking an egg, rusting of an iron pan.
Question 6
1 / -0

For rusting of iron to take place _______ are required.

A
$${O_2}$$ and $${CO_2}$$

B
$${H_2O}$$ and $${N_2}$$

C
$${H_2O}$$ and $${O_2}$$

D
$${H_2O}$$ and $${H_2}$$

Solution

Rusting of iron consists of the formation of hydrated oxide, $$Fe_2O_3.xH_2O$$. It is an electrochemical process that requires the presence of water, oxygen, and an electrolyte.
Question 7
1 / -0

Some pieces of chalk were taken and mixed with water. In this change, how many new substances are formed?

A
1

B
2

C
3

D
No new substance is formed

Solution

No new substances are formed. The chalk when mixed with water, no chemical reaction occurs. The chalk disperses in water which can be separated by filtration.
Question 8
1 / -0

Two changes are stated below:
(i) A piece of magnesium gives of bright flames when burnt.
(ii) A piece of iron glows red when heated strongly.
Which of these is a chemical change?

A
i only

B
ii only

C
Both i and ii

D
None of the above

Solution

i) When magnesium is burnt, it reacts with the air and gives bright flames and this change cannot be reversed. It is a chemical change. The new product form is Magnesium oxide.

ii) When iron heated strongly it turns red. When heating is stopped it cools and gets back to its original form. So this is a physical change.
Question 9
1 / -0

Adding sodium chloride to water is a:

A
physical change

B
chemical change

C
irreversible change

D
None of these

Solution

Physical changes are changes in the physical properties of substances. No new substances are formed in these changes.

The addition of sodium chloride to water does not result in the formation of any new substance, hence it is a physical change. Also, sodium chloride can be reversed back to its original state by simple evaporation of water. Therefore, it is a reversible change.

So, the correct option is A.
Question 10
1 / -0

Two changes are stated below:
(i.) A piece of magnesium gives of bright flames when burned.
(ii). A piece of iron glows red when heated strongly.
Which of these is a physical change?

A
Only i

B
Only ii

C
Both i and ii

D
Neither i nor ii

Solution

When magnesium is burnt, it reacts with oxygen and gives bright flames. This is a chemical change and cannot be reversed.
When iron is heated strongly, it turns red. When heating is stopped, it cools and gets backs to its original form. So this is a physical change. Hence option B is correct.

User

Question Analysis

Correct -
Wrong -
Skipped -

My Perfomance

Score
-
out of -
Rank
-
out of -

Re-Attempt Weekly Quiz Competition

Physical and Chemical Changes Test - 9

Result

Physical and Chemical Changes Test - 9

Score

-

Rank

-

SHARING IS CARING

Question 1

It is a chemical change because a new substance is formed

It is a physical change because the original substances can be recovered

It is a chemical change because there is exchange of heat

It is a physical change because there is a slight change in colour

Solution

Question 2

Physical change

Chemical change

Both A and B

Neutralization reaction

Solution

Question 3

The properties of ash will be similar to wood

The properties of ash will be similar to oxygen

The properties of ash will be different from both wood and oxygen

None of the above

Solution

Question 4

Digestion of food

Precipitation of rain and snow

Rusting of iron

Burning of paper

Solution

Question 5

temporary, reversible and a new substance is produced

always accompanied by exchange of light

permanent, irreversible and a new substance is produced

never accompanied by exchange of light and heat energy

Solution

Question 6

$${O_2}$$ and $${CO_2}$$

$${H_2O}$$ and $${N_2}$$

$${H_2O}$$ and $${O_2}$$

$${H_2O}$$ and $${H_2}$$

Solution

Question 7

1

2

3

No new substance is formed

Solution

Question 8

i only

ii only

Both i and ii

None of the above

Solution

Question 9

physical change

chemical change

irreversible change

None of these

Solution

Question 10

Only i

Only ii

Both i and ii

Neither i nor ii

Solution

User

Question Analysis

My Perfomance

Score

-

Rank

-

Results Announcement on: coming Monday

Stay Tuned: We’ll update you on your result via email or SMS.