Atoms and molecules questions

Very Short Answer Questions

1. What is an atom?
2. What is a molecule?
3. Define atomic mass.
4. Define molecular mass.
5. What is a chemical formula?
6. What is an ion?
7. What is valency?
8. What is the formula of water?
9. What is the atomicity of oxygen?
10. Name the smallest particle of an element.

Short Answer Questions

1. Differentiate between atom and molecule.
2. What are polyatomic ions? Give two examples.
3. Explain the law of conservation of mass.
4. State the law of constant proportions.
5. What is meant by atomicity? Give examples.
6. Write the chemical formula of:
   • Sodium chloride
   • Calcium oxide
   • Ammonia
   • Carbon dioxide
7. How do you calculate molecular mass? Explain with an example.
8. What are isotopes?

Long Answer Questions

1. Explain Daltons atomic theory.
2. Describe the laws of chemical combination.
3. How are chemical formulae written? Explain with examples.
4. Calculate the molecular mass of:
   • HSO
   • CaCO
   • NaOH
5. Explain the concept of mole.