Chemistry
Harsh performed the following experiments in the laboratory. State one significant observation made by Harsh when:
(a) he added concentrated sulphuric acid to blue vitriol.
(b) he passed ammonia gas over heated PbO.
(c) sodium hydroxide solution was added to CuSO4 solution by him.
Related Questions
Justify the following statements:
(a) As one moves down a group, the reducing property of elements increases.
(b) Aluminium oxide cannot be reduced by carbon monoxide.
Arrange the following as per the instructions given in the brackets:
(a) Mg, S, Si, P [decreasing order of atomic size]
(b) Cl, I, Br, F [increasing electronegativity]
(c) K, Na, Rb, Li [decreasing metallic character]
Choose the letters L, M, N, O & P to match the description (a) to (c) given below:
[L – Ammonia, M – Nitrogen, N – Hydrogen sulphide, O – Hydrogen chloride gas, P – Nitrogen dioxide]
(a) When this gas comes in contact with ammonia dense white fumes are seen.
(b) The gas that turns moist lead acetate paper silvery black.
(c) The gas produced on heating lead nitrate.
Smith wrote the following statements incorrectly. Insert a word to correct the statements.
(a) Lead bromide conducts electricity.
(b) Copper reacts with nitric acid to form nitrogen dioxide gas.
(c) Bromoethane reacts with sodium hydroxide to produce ethanol and sodium bromide.