Assertion :When liquid water is cooled, it contracts until a temperature of approximately 4 degrees Celsius is reached. After that, it expands slightly until it reaches the freezing point. Reason: The distance between the H-O bond is more than the O-O attraction in the water. Hence, the water freezing over into ice is held together not by the O-O attraction but by the H-O attraction.

Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Assertion is correct but Reason is incorrect

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Both Assertion and Reason are incorrect

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
Assertion
When liquid water is cooled, it contracts until a temperature of approximately 4 $^{o} C$ is reached. After that, it expands slightly until it reaches the freezing point.

Reason
The distance between the $H - O$ bond is more than the $O - O$ bond in the water. Hence, the water freezing over into ice is held together not by the $O - O$ attraction but by the $H - O$ attraction.

Hence, both Assertion and Reason are correct and Reason is the correct explanation for Assertion.

The density of water is maximum at 4 $^{o} C$ .

The density of water decreases when you cool it from 4 $^{o} C$ to 0 $^{o} C$ .

Hence the correct option is A.

Suggest Corrections

Similar questions

Q. Assertion: The compressibility factor for

H_{2}

and

H e

(1 + \frac{P b}{R T})

Reason: The compressibility factor for

H_{2}

and

H e

can be derived from Van der Waal's equation.

Q. Assertion
If BOD level of water in reservoir is less than 5 ppm it is not polluted.

Reason
High biological oxygen demand means low activity of bacteria in water.

Assertion (A) Bond angle in ethers is slightly less than the tetrahedral angle.
Reason (R) There is a repulsion between the two bulky (- R) groups.
(a) Assertion and reason both are correct and reason is correct explanation of assertion.
(b) Assertion and reason both are wrong statements.
(c) Assertion is correct statement but reason is wrong statement.
(d) Assertion is wrong statement but reason is correct statement.
(e) Both assertion and reason are correct statements but reason is not correct explanation of assertion.

Q. For the following Assertion and Reason, the correct option is:
Assertion: The

p H

of water increases with increase in temperature.

Reason: The dissociation of water into

H^{+}

and

O H^{-}

an exothermic reaction.

Q. Assertion : In the bonding molecular orbital (MO) of

H_{2}

, the electron density is increased between the nuclei.
Reason : The bonding MO is

ψ_{A} + ψ_{B}

, which shows destructive interference of the combining electron waves.

Join BYJU'S Learning Program