Chemistry

If the heat of combustion of hydrogen is -285.8kJ; What is the heat of formation of water?

A. +571.6 kJ B. -571.6 kJ C. -285.8 kJ D. +285.8 kJ Correct Answer: Option C = -285.8 kJ

4 years ago

How many moles of sodium trioxocarbonate (IV) are there in a 25 cm³ solution which required 10cm³ of 0.05 mol dm-³ hydrochloric acid solution to neutralize it?

Na2CO3(g) + 2HCl(aq) → 2NaCl(aq) + H2O(l) + CO2(g) A. 1.000 mole B. 0.100 mole C. 0.010 mole` D. 0.111…

4 years ago

In the electrolysis of CuSO4(g) using platinum electrodes; the reaction at the anode is?

A. 4H+ + 4e− → 2H2 B. 4OH− + 4e− → 2H2O + O2 C. 2OH− + 2e− → 2OH…

4 years ago

In which of the following is the oxidation number of sulphur equal to -2?

A. SO3 B. S8 C. H2S D. SO2 Correct Answer: Option C = H2S

4 years ago

The solution that will conduct the highest amount of electricity is?

A. 0.5 mol dm−³ of hydrochloric acid B. 2.0 mol dm−³ of hydrochloric acid C. 0.5 mol dm−³ ethanoic acid…

4 years ago

Zinc and carbon rods are used as anode and cathode respectively in a?

A. Leclanche cell B. lead accumulator C. Daniel cell D. voltaic cell Correct Answer: Option A - Leclanche cell Explanation…

4 years ago

The ion that can be used as an oxidizing agent is?

  A. Au³+ B. Fe³+ C. ClO− D. Ca²+ Correct Answer: Option C = ClO− Explanation All the other options…

4 years ago

The mass of carbon(IV)oxide produced on burning 78 g of ethyne is? [C =12, O = 16, H = 1]

2C2H2(g) + 5O2(g) → 4CO2(g) + 2H2O(g) A. 264 g B. 39 g C. 352 g D. 156 g Correct…

4 years ago

If 30cm³ of gas at 50°C is warmed to 80°C at a fixed pressure; the fractional increase in volume is?

A. 0.009 B. 0.093 C. 0.910 D. 1.090 Correct Answer: Option D = 1.090

4 years ago

The idea of planetary electron was that of?

A. Rutherford B. Thompson C. Bohr D. Dalton Correct Answer: Option A - Rutherford

4 years ago