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Assertion: The concentration of pollutan...

Assertion: The concentration of pollutants in water or atmosphere is often expressed in terms of ppm.
Reason: Concentration in parts per million can be expressed as mass to mass, volume to volume and mass to volume

A

If both assertion and reason are true and reason is the correct explanation of assertion.

B

If both assertion and reason are true, but reason is not the correct explanation of assertion.

C

If assertion is true, but reason is false.

D

If both assertion and reason are false

Text Solution

Verified by Experts

The correct Answer is:
B
The concentration of pollutants in water or atmosphere is often expressed in volumetric terms i.e., parts per million (ppm). Parts per million is the mass of chemical contaminant per unit volume of water or air. Concentration in parts per million can be expressed as mass to mass, volume to volume and mass to volume. Thus, both assertion and reason are true, but reason is not the correct explanation of assertion.
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Knowledge Check

  • If the pressure is doubled for a fixed mass of gas, its volume will become

    A
    4 times
    B
    1/2 times
    C
    2 times
    D
    No change

  • Assertion : Soluable fluoride is often added to drinking water to bring its concentration up to 1 ppm. Reason : F^(-) ion concentration above 2 ppm causes brown mottling of teeth.

    A
    If both assertion and reason are true and reason is the correct explanation of assertion.
    B
    If both assertion and reason are true but reason is not the c orrect explanation of assertion.
    C
    If assertion is true but reason is false.
    D
    If both assertion and reason are false.