Advertisements
Advertisements
Question
When heated, potassium permanganate decomposes according to the following equation:
\[\ce{2KMnO4 -> \underset{solid residue}{K2MnO4 + MnO2} + O2}\]
Given that the molecular mass of potassium permanganate is 158 g, what volume of oxygen (measured at room temperature) would be obtained by the complete decomposition of 15.8 g of potassium permanganate? (Molar volume at room temperature is 24 litres). [K = 39, Mn = 55, O = 16]
Advertisements
Solution
| 2KMnO4 | → | K2MnO4 | + | MnO2 | + | O2 |
| 2[39 + 55 + 64] | 24 lit | |||||
| 2 × 158 = 316 g |
Vol. of O2 produced by 316 g of KMnO4 = 24 lit.
∴ Vol. of O2 produced by 15.8 of KMnO4 = `(24 xx 15.8)/316`
= 1.2 lit.
APPEARS IN
RELATED QUESTIONS
Prove the Following :
2 X V.D. = Molecular mass.
Calculate the relative molecular mass of Ammonium sulphate.
(use K = 39, Cl = 35.5, O = 16, C = 12, H = 1, Na = 23, N = 14, S= 32)
Concentrated nitric acid oxidises phosphorus to phosphoric acid according to the following equation:
\[\ce{P + 5HNO3 -> H3PO4 + H2O + 5NO2}\]
- What mass of phosphoric acid can be prepared from 6.2 g of phosphorus?
- What mass of nitric acid will be consumed at the same time?
- What will be the volume of steam at the same time measured at 760 mm Hg pressure and 373°C?
(H = 1; N = 14; O = 16; P = 31∴ )
Calculate the percentage of phosphorous in the fertilizer superphosphate, Ca(H2PO4)2. [Ca = 40, H =1, P =31, O = 16] (Correct to 1 decimal place)
A certain gas 'X' occupies a volume of 100 cm3 at S.T.P. and weighs 0.5 g. Find its relative molecular mass.
Calculate the relative molecular mass of:
CuSO4. 5H2O
Calculate the number of hydrogen atoms in 0.1 mole of H2SO4.
If a crop of wheat removes 20 kg of nitrogen per hectare of soil, what mass of the fertilizer, calcium nitrate Ca(NO3)2 would be required to replace the nitrogen in a 10 hectare field?
Ammonia burns in oxygen and the combustion, in the presence of a catalyst, may be represented by;
\[\ce{2NH3 + 2 1/2O2 -> 2NO + 3H2O}\] [H = 1, N = 14, O = 16]
What mass of steam is produced when 1.5 g of nitrogen monoxide is formed?
67.2 litres of hydrogen combines with 44.8 litres of nitrogen to form ammonia under specific conditions as:
\[\ce{N2_{(g)} + 3H2_{(g)} -> 2NH3_{(g)}}\]
Calculate the volume of ammonia produced. What is the other substance, if any, that remains in the resultant mixture?
