Question

Mention whether the following statements are true or false. Correct the false statements.

a) An aqueous solution of copper sulphate is homogeneous.

b) Milk is a pure substance.

c) A molecule of sulphur is monoatomic.

Answer 1

1. True
2. false because it is a colliod
3. false because it is diatomic

Answer 2

a) An aqueous solution of copper sulphate is termed as homogeneous: True

b) Milk is said to be a pure substance: False

c) A molecule of sulphur is known as  monatomic: False

Explanation:

• A homogenous mixture is a mixture that appears uniform and as a single phase to the eye. The composition remains uniform throughout the mixture and the solute is completely dissolved in the solvent. Water is a homogenous mixture of many dissolved gases and minerals. Generally, all solutions are homogeneous in nature like sugar or salt solutions, aqueous copper sulphate solution, etc.  
• A pure substance is the one that is made up of a single type of atom or molecule throughout with a definite composition and without impurities or contamination. Gold, diamonds, water are some of the examples of pure substances. Milk is a colloidal mixture containing different types of molecules like fatty acids, carbohydrates, proteins, etc.that are dissolved in the solvent water.
• A monatomic element is made up of a single atom. Noble gases like helium, neon, argon etc are monatomic elements. An element is considered polyatomic if it is composed of different elements in a definite composition and bonded chemically. Sulphur is a polyatomic element with eight atoms.