Chemistry

When iron is exposed to moist air; it gradually rusts. This is due to the formation of?

A. hydrate iron (III) oxide B. anhydrous iron (III) oxide C. anhydrous iron (II) oxide D. hydrate iron (II) oxide…

5 years ago

A constituent common to bronze and solder is?

A. lead B. silver C. copper D. tin Correct Answer: Option D - tin

5 years ago

Which of the following is used in rocket fuels?

A. HNO3 B. CH3COOH C. H2SO4 D. HCl Correct Answer: Option A - HNO3

5 years ago

The brown ring observed after the addition of a stream of concentrated tetraoxosulphate (VI) acid confirmed the presence of?

To a solution of an unknown compound, a little dilute tetraoxosulphate (VI) acid was added with some freshly prepared iron…

5 years ago

What happens to the equilibrium constant of the reaction below if the temperature is increased?

2H2(g) + O2(g) → 2H2O(g) ΔH = -ve A. it is unaffected B. it becomes zero C. it decreases D.…

5 years ago

In the preparation of oxygen by heating KClO3 in the presence of MnO2; only moderate heat is needed because the catalyst acts by?

A. lowering the pressure of the reaction B. increasing the surface area of the reactant C. increase the rate of…

5 years ago

If a reaction is exothermic and there is a great disorder, it means that?

A. the reaction is static B. the reaction is in a state of equilibrium C. there will be a large…

5 years ago

In which of the following is the entropy change positive?

A. Thermal dissociation of ammonium chloride B. Reaction between an acid and a base C. Addition of concentrated acid to…

5 years ago

Iron can be protected from corrosion by coating the surface with?

A. gold B. silver C. copper D. zinc Correct Answer: Option D - zinc

5 years ago