On the basis of composition of matter, milk is considered to be:

When a mixture of iron powder and sulphur powder is heated strongly to form iron sulphide, then heat energy is:

The property/properties which enable copper metal to be used for making electric wires is/are:

Which of the following statements are true for pure substances?

(i) pure substances contain only one kind of particles

(ii) pure substances may be compounds or mixtures

(iii) pure substances have the same composition throughout

(iv) pure substances can be exemplified by all elements other than nickel

Which of the following are homogeneous in nature?

(i) ice (ii) wood

(iii) soil (iv) air