Which of the following pairs will give displacement reactions?

An element reacts with oxygen to give a compound with a high melting point. This compound is also suitable in water. The element is likely to be

The ability of metals to be drawn into thin wire is known as

An element X forms an oxide which turns red litmus blue. Identify whether X is a metal or non-metal

Name a non-metal which is lustrous and a metal which is non-lustrous. 

Name the metal which reacts with a very dilute HNO₃ to evolve hydrogen gas.

Why is sodium kept immersed in kerosene oil?

What would you observe when zinc is added to a solution of Iron (II) sulphate? Write the chemical reaction that takes place.

Write equations for the reactions of :
(i) iron with steam
(ii) calcium and potassium with water

List three properties of sodium in which it differs from the general physical properties of most metals.

(i) A non-metal X exists in two different forms Y and Z. Y is the hardest natural substance whereas Z is a good conductor of electricity. Identity X, Y, Z.
(ii) A element, X, on reaction with oxygen forms an oxide XO₂. The oxide when dissolved in water turns blue litmus red. State whether element X is a metal or a non-metal.
(iii) Name the metal which is alloyed with copper to make bronze.

Give reasons for the following:
(i) Aluminium is a reactive metal but is still used for packing food articles.
(ii) Calcium starts floating when water is added to it.

Write the balanced chemical equation for the following reactions:
(i) When copper is heated in air.
(ii) When aluminum is heated in air.
(iii) Aluminium oxide reacts with sodium hydroxide.

Of the three metals X, Y and Z, X reacts with cold water, Y with hot water and Z with steam only. Identify X, Y and Z and also arrange them in order of increasing reactivity.