Download App

Hydrogen — Chemistry STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceChemistryHydrogen1 Mark
MCQ
Assertion $(A)$ : Permanent hardness of water is removed by treatment with washing soda.
Reason $(R)$ : Washing soda reacts with soluble magnesium and calcium sulphate to form insoluble carbonates.
  • ✓
    $A$ and $R$ both are correct, and $R$ is the correct explanation of $A.$
  • B
    $A$ and $R$ both are correct, but $R$ is not the correct explanation of $A$.
  • C
    $A$ is true but $R$ is false.
  • D
    $A$ and $R$ both are false.
✓

Answer

Correct option: A.
$A$ and $R$ both are correct, and $R$ is the correct explanation of $A.$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "Assertion (A) & Reason (B) MCQ" from Hydrogen→Hydrogen — all question types→Chemistry STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

Assertion (A): Overlapping in benzene is $sp ^2- sp ^2$ type.
Reason (R): C-C bond length in benzene is $1.3 \stackrel{\circ}{A}$.
→
Note : In the following questions a statement of Assertion $(A)$ followed by a statement of Reason $(R)$ is given. Choose the correct option out of the choices given below each question.
Assertion $(A)$ : Energy of resonance hybrid is equal to the average of energies of all canonical forms.
Reason $(R)$ : Resonance hybrid cannot be presented by a single structure.
→
Directions : In the following questions, the Assertions $(A) $ and Reason $(s) (R)$ have been put forward. Read both the statements carefully and choose the correct alternative from the following:
Assertion: Thallium compounds are stable in $+ 1$ oxidation state.
Reason: The $6s^2$ electrons in $\ce{Tl}$ show reluctance in participating in bond formation.
→
Note : In the following questions a statement of Assertion $(A)$ followed by a statement of Reason $(R)$ is given. Choose the correct option out of the choices given below each question.
Assertion $(A)$ : Though the central atom of both $\mathrm{NH}_3$ and $\mathrm{H}_2 \mathrm{O}$ molecules are $\mathrm{sp}^3$ hybridised, yet $\mathrm{H}-\mathrm{N}-\mathrm{H}$ bond angle is greater than that of $\mathrm{H}-\mathrm{O}-\mathrm{H}$.
Reason $(R)$ : This is because nitrogen atom has one lone pair and oxygen atom has two lone pairs.
→
Note : In the following questions a statement of Assertion $(A)$ followed by a statement of Reason $(R)$ is given. Choose the correct option out of the choices given below each question.
Assertion $(A)$ : Silicons are water repelling in nature.
Reason $(R)$ : Silicons are organosilicon polymers, which have $\left(\mathrm{R}_2 \mathrm{SiO}{-}\right)$ as repeating unit.
→
Assertion (A): The energy of quantum of radiation is given by $E = h \nu$.
Reason (R): Quantum in the energy equation signifies the principal quantum number.
→
Assertion (A): In case of isoelectronic ions the ionic size increases with the increase in atomic number.
Reason (R): The greater the attraction of nucleus, greater is the ionic radius.
→
Note : In the following question a statement of Assertion $(A)$ followed by a statement of Reason $(R)$ is given. Choose the correct option out of the choices given below:
Assertion $(A)$ : If $\text{BOD}$ level of water in a reservoir is less than $5$ ppm it is highly polluted.
Reason $(R)$ : High biological oxygen demand means low activity of bacteria in water.
→
In the following Questions, the Assertion and Reason hrve been put forfiird. Read the statements csrefully end choose the correct alternative from the following:
Assertion : A Mixture of $o-$ nitrophenol and $p-$ nitrophenol can be separated by steam distillation.
Reason : $p-$ nitrophenol is steam volatile while $o-$ nitrophenol is not steam volatile.
→
Assertion (A): Fluoride has the lowest and iodide has the highest boiling point.
Reason (R): Boiling points of haloalkanes increases with increasing atomic mass.
→