Chemistry
Assertion (A): On adding ammoniacal silver nitrate to ethyne, it gives a white precipitate.
Reason (R): The above reaction forms silver acetylide.
- 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.
Answer
Both A and R are true and R is the correct explanation of A.
Explanation— Ethyne (HC≡CH) reacts with ammoniacal silver nitrate to give a white precipitate of silver acetylide (AgC≡CAg). Thus Assertion (A) is correct. The precipitate’s identity—silver acetylide—explains why the white solid appears, so Reason (R) is also true and provides the correct explanation for the assertion.
Related Questions
Assertion (A): The brown colour of bromine fades when it is added to ethylene.
Reason (R): Ethylene shows substitution reactions.
- 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): Acetylene burns with a sooty flame.
Reason (R): Acetylene contains a greater carbon content.
- 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): Carboxylic acids react with alcohol in presence of concentrated H2SO4 to produce a fruity smell.
Reason (R): It is due to the formation of an aldehyde.
- 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.
Choose the correct word/phrase from within the brackets to complete the following sentences:
(i) The catalyst used for conversion of ethene to ethane is commonly …………… (nickel/iron/cobalt)
(ii) When acetaldehyde is oxidized with acidified potassium dichromate, it forms …………… (ester / ethanol / acetic acid)
(iii) Ethanoic acid reacts with ethanol in the presence of concentrated H2SO4, so as to form a compound and water. The chemical reaction which takes place is called …………… (dehydration/hydrogenation/esterification)
(iv) Write the equation for the reaction taking place between 1,2-dibromoethane and alcoholic potassium hydroxide.
(v) The product formed when ethene gas reacts with water in the presence of sulphuric acid …………… (ethanol / ethanal / ethanoic acid)