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Chemistry Questions

Question 361:

Naphthalene when heated melts at 354 K (81 <sup style='font-size: smaller;'>o</sup>C). At this temperature the molecules of naphthalene

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A Decompose into smaller molecules
B Change their shape
C Are oxidized by atmospheric oxygen
D Contract
E Become mobile as the inter molecular forces are broken

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Question 362:

The ratio of the number of molecules in 2g of hydrogen to that in 16g of oxygen is

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A 2:1
B 1:1
C 1:2
D 1:4
E 1:8

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Question 363:

The balanced equation for the reaction of tetraoxosulphate(VI)acid with aluminium hydroxide to give water and aluminium tetraoxosulphate(VI) is

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A H<sub style='font-size: smaller;'>2</sub>SO<sub style='font-size: smaller;'>4</sub> + Al(OH)<sub style='font-size: smaller;'>2</sub> \(\to\) 2H<sub style='font-size: smaller;'>2</sub>O + AlSO<sub style='font-size: smaller;'>4</sub>
B 3H<sub style='font-size: smaller;'>2</sub>SO<sub style='font-size: smaller;'>4</sub> + 2Al(OH)<sub style='font-size: smaller;'>3</sub> \(\to\) 6H<sub style='font-size: smaller;'>2</sub>O + Al<sub style='font-size: smaller;'>2</sub>(SO<sub style='font-size: smaller;'>4</sub>)<sub style='font-size: smaller;'>3</sub>
C 3H<sub style='font-size: smaller;'>2</sub>SO<sub style='font-size: smaller;'>4</sub> + 2AlH \(\to\) 6H<sub style='font-size: smaller;'>2</sub>O + Al(SO<sub style='font-size: smaller;'>4</sub>)<sub style='font-size: smaller;'>3</sub>
D 3H<sub style='font-size: smaller;'>2</sub> SO<sub style='font-size: smaller;'>4</sub> + 2Al(OH)<sub style='font-size: smaller;'>3</sub> \(\to\) Al(SO<sub style='font-size: smaller;'>4</sub>)<sub style='font-size: smaller;'>3</sub>
E H<sub style='font-size: smaller;'>2</sub>SO<sub style='font-size: smaller;'>4</sub> + Al(OH)<sub style='font-size: smaller;'>3</sub> \(\to\) H<sub style='font-size: smaller;'>2</sub>O + Al<sub style='font-size: smaller;'>2</sub>(SO<sub style='font-size: smaller;'>4</sub>)<sub style='font-size: smaller;'>3</sub>

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Question 364:

Which of the following mixtures would result in a solution of pH greater than 7?

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A 25.00 cm<sup style='font-size: smaller;'>3</sup> of 0.05 M H<sub style='font-size: smaller;'>2</sub>SO<sub style='font-size: smaller;'>4</sub> and 25.00cm<sup style='font-size: smaller;'>3</sup> of 0.50 M Na<sub style='font-size: smaller;'>2</sub>CO<sub style='font-size: smaller;'>3</sub>
B 25.00 cm<sup style='font-size: smaller;'>3</sup> of 0.05 M H<sub style='font-size: smaller;'>2</sub>SO<sub style='font-size: smaller;'>4</sub> and 25.00 cm<sup style='font-size: smaller;'>3</sup> of 0.10 M NaHCO<sub style='font-size: smaller;'>3</sub>
C 25.00 cm<sup style='font-size: smaller;'>3</sup> of 0.11 MH<sub style='font-size: smaller;'>2</sub>SO<sub style='font-size: smaller;'>4</sub> and 25.00cm<sup style='font-size: smaller;'>3</sup> 0. 10 M NaOH
D 25.00cm<sup style='font-size: smaller;'>3</sup> of 0.11 MH<sub style='font-size: smaller;'>2</sub> SO<sub style='font-size: smaller;'>4</sub> and 50.00 cm<sup style='font-size: smaller;'>3</sup> of 0.05 M NaOH
E 25.00cm<sup style='font-size: smaller;'>3</sup> of 0.25 M H<sub style='font-size: smaller;'>2</sub>SO<sub style='font-size: smaller;'>4</sub> and 50.00cm<sup style='font-size: smaller;'>3</sup> of 0.20 M NaOH

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Question 365:

In which of the following reactions does hydrogen peroxide act as a reducing agent?

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A H<sub style='font-size: smaller;'>2</sub>S + H<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>2</sub> \(\to\) S + 2H<sub style='font-size: smaller;'>2</sub>O
B PbSO<sub style='font-size: smaller;'>3</sub> + H<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>2</sub> \(\to\) PbSO<sub style='font-size: smaller;'>4</sub> + H<sub style='font-size: smaller;'>2</sub>O
C 2I+ 2H<sup style='font-size: smaller;'>+</sup> + H<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>2</sub> \(\to\) I<sub style='font-size: smaller;'>2</sub> + 2H<sub style='font-size: smaller;'>2</sub>O
D PbO<sub style='font-size: smaller;'>2</sub> + 2HNO<sub style='font-size: smaller;'>3</sub> + H<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>2</sub> \(\to\) Pb(NO<sub style='font-size: smaller;'>3</sub>)<sub style='font-size: smaller;'>2</sub> + 2H<sub style='font-size: smaller;'>2</sub>O + O<sub style='font-size: smaller;'>2</sub>
E SO<sub style='font-size: smaller;'>2</sub> + H<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>2</sub> \(\to\) H<sub style='font-size: smaller;'>2</sub>SO<sub style='font-size: smaller;'>4</sub>

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