Which of the following reaction produces hydrogen ?
Mg + H2O
H2S2O8 + H2O
BaO2 + HCl
Na2O2 + 2HCl
The length of C - C bond in benzene is :
1.22 Ao
1.54 Ao
1.39 Ao
1.56 Ao
C.
1.39 Ao
The bond length C = C (single bond as in ethane) is 1.54 A and C = C double bond as in ethene is 1.33 Ao . The carbon carbon bond length in benzene has been found to be 1.39Ao which lies between single and double bond length value.
Assertion: Stannous chloride gives a grey precipitate with mercuric chloride, but stannic chloride does not do so.
Reason: Stannous chloride is a powerful oxidising an agent which oxidises mercuric chloride to metallic mercury.
If both assertion and reason are true and the reason is a correct explanation of the assertion.
If both the assertion and reason are true but the reason is not a correct explanation of the assertion.
If the assertion is true but the reason is false.
If both the assertion and reason are false.
Assertion: Diamond is a bad conductor.
Reason: Graphite is a good conductor.
If both assertion and reason are true and reason is a correct explanation of the assertion.
If both the assertion and reason are true but the reason is not a correct explanation of the assertion.
If the assertion is true but the reason is false.
If both the assertion and reason are false.