Chemistry
Assertion (A): Hydrogen and alkali metals react with a black copper oxide to give red/brown copper.
Reason (R): Hydrogen and alkali metals are good oxidising agents.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Related Questions
The table given below shows the reaction of a few elements with acids and bases to evolve hydrogen gas.
Element Acid Base (A) X X (B) ✓ ✓ (C) ✓ X (D) ✓ ✓ Which of these elements will form amphoteric oxides.
- A and D
- B and D
- A and C
- B and D
Assertion (A): Though hydrogen is lighter than air, it is not collected by the downward displacement of air but by the downward displacement of water.
Reason (R): Hydrogen is slightly soluble in water.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Assertion (A): Granulated zinc is preferred over pure zinc in the preparation of hydrogen using dilute acids.
Reason (R): Granulated zinc contains traces of impurities which have a slight catalysing effect on the reaction.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Assertion (A): In Bosch process, hydrogen and carbon dioxide are formed.
Reason (R): Hydrogen and carbon dioxide are separated by passing through ammoniacal cuprous chloride solution.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.