Download App

Metals and Non-Metals — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10ScienceMetals and Non-Metals1 Mark
MCQ
For two statements are given $-$ one labelled Assertion $(A)$ and the other labelled Reason $(R)$. Select the correct answer to these questions from the codes $\ce{(a), (b), (c)}$ and $(d)$ as given below :
Assertion : On reacting with water, calcium starts floating over water.
Reason : Calcium reacts with cold water at room temperature.
  • A
    Both $A$ and $R$ are true, and $R$ is correct explanation of the assertion.
  • ✓
    Both $A$ and $R$ are true, but $R$ is not the correct explanation of the assertion.
  • C
    $A$ is true, but $R$ is false.
  • D
    $A$ is false, but $R$ is true.
✓

Answer

Correct option: B.
Both $A$ and $R$ are true, but $R$ is not the correct explanation of the assertion.
Calcium floats over water because the bubbles of hydrogen gas formed get stick to the surface of the water.

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 - Reasoning (1 Marks)" from Metals and Non-Metals→Metals and Non-Metals — all question types→Science STD 10 question papers→CBSE Board STD 10 question papers→CBSE Board question paper generator→

Similar questions

For two statements are given $-$ one labelled Assertion $(A)$ and the other labelled Reason $(R)$. Select the correct answer to these questions from the codes $\ce{(a), (b), (c)}$ and $(d)$ as given below :
Assertion : Atomic size of potassium is greater than that of sodium.
Reason : As we go down the group, atomic radius increases.
→
For two statements are given $-$ one labelled Assertion $(A)$ and the other labelled Reason $(R).$ Select the correct answer to these questions from the codes $\ce{(a), (b), (c)}$ and $(d)$ as given below:
Assertion : If mother is homozygous for black hair and father has red hair then their child can inherit black hair.
Reason : Gene for black hair is recessive to gene for red hair in humans.
→
For two statements are given $-$ one labelled Assertion $(A)$ and the other labelled Reason $(R)$. Select the correct answer to these questions from the codes $\ce{(a), (b), (c)}$ and $(d)$ as given below :
Assertion : In the case of concave mirror, the minimum distance between real object and its real image is zero.
Reason : If concave mirror forms virtual image of real object, the image is magnified.
→
For two statements are given $-$ one labelled Assertion $(A)$ and the other labelled Reason $(R).$ Select the correct answer to these questions from the codes $\ce{(a), (b), (c)}$ and $(d)$ as given below :
Assertion : The rainbow is seen when the sun is behind the observer.
Reason : Rainbow is produced due to dispersion of white light by small rain drops hanging in the air after the rain.
→
For two statements are given $-$ one labelled Assertion $(A)$ and the other labelled Reason $(R).$ Select the correct answer to these questions from the codes $\ce{(a), (b), (c)}$ and $(d)$ as given below :
Assertion : The oxides of sulfur and phosphorus are acidic in nature.
Reason : Metal oxides are basic in nature.
→
Assertion (A): When pea plants (pureline) having round yellow seeds are crossed with pureline plants having wrinkled green seeds, then all pea plants obtained in $\mathrm{F}_{1}$ generation bear wrinkled green seeds.
Reason (R): Round and yellow seeds are dominant to wrinkled and green seeds.
→
Assertion (A): Biotic components of ecosystem continuously require energy to carry on life processes.
Reason (R): Abiotic components are the non-living factors of the ecosystem.
→
For two statements are given-one labelled Assertion $(A)$ and the other labelled Reason $(R)$. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below:
Assertion: $\ce{2H_2S(g) + O_{2(g)} → 2S_{(g)} + 2H_2O_{(l)} }$lt is a redox reaction.
Reason: ln redox reaction, oxidation and reduction take place simultaneously.
→
In the following questions, a statement of Assertion is given by the corresponding statement of Reason. Of the statements, mark the correct answer as :
Assertion : $\text{ENT}$ specialist use a concave mirror as a head mirror to concentrate light on the body parts like eye, ear, nose etc.
Reason : A concave mirror is more effective and easily available.
→
For two statements are given-one labelled Assertion $(A)$ and the other labelled Reason $(R)$. Select the correct answer to these questions from the codes $\ce{(a), (b), (c)}$ and $(d)$ as given below :
Assertion : The size of the mirror affect the nature of the image.
Reason : Small mirrors always form virtual images.
→