G9-SCI-L3 Atoms and Molecules

Who laid the foundation of chemical sciences by establishing the law of conservation of mass?

• Antoine Lavoisier
• John Dalton
• Joseph Proust
• Maharishi Kanad

What is the law of constant proportions also known as?

• Law of Conservation of Mass
• Law of Definite Proportions
• Dalton's Atomic Theory
• Law of Chemical Combination

According to Dalton's atomic theory, what are atoms?

• Indivisible particles
• Tiny particles made up of protons and neutrons
• Particles that can be created or destroyed
• Particles that combine in random ratios

What is the smallest particle of an element or a compound that is capable of an independent existence and shows all the properties of that substance called?

• Atom
• Molecule
• Ion
• Compound

What is the formula of sodium carbonate?

• NaCO3
• Na2CO3
• NaCO2
• Na2CO2

What is the molecular mass of water (H2O)?

• 16 u
• 18 u
• 20 u
• 22 u

What is the formula of ammonium sulphate?

• (NH4)2SO4
• NH4SO4
• NH4SO3
• NH4)2SO3

What is the valency of chlorine?

• 1
• 2
• 3
• 4

What is the valency of oxygen?

• 1
• 2
• 3
• 4

What is the valency of aluminium?

• 1
• 2
• 3
• 4