Atoms and Molecules short 1

Question 1

Who came up with the name of atoms ?

Answer 1

Democritus

Question 2

Who laid the foundation for chemical sciences ?

Answer 2

Antoine L. Lavoisier

Question 3

What are the laws established by Lavoisier and Joseph L. Proust

Answer 3

1] Law of conservation of mass
2] Law of constant proportions

Question 4

What is the ratio of the mass of hydrogen to the mass of oxygen in water ?

Answer 4

1:8

Question 5

What is the ratio of the mass of nitrogen to the mass of hydrogen in ammonia ?

Answer 5

14:3

Question 6

The law of constant proportions is also known as

Answer 6

Law of definite proportions

Question 7

What is the law of constant proportions ?

Answer 7

In a chemical substance the elements are always present in definite proportions by mass.

Question 8

What are Atoms ?

Answer 8

The building blocks of all matter are atoms.

Question 9

Who suggested that the symbols of elements be
made from one or two letters of the name of the element ?

Answer 9

Berzilius

Question 10

Full form of IUPAC ?

Answer 10

International Union of Pure and Applied Chemistry

Question 11

Name some of the elements whose name has been taken from other languages ?

Answer 11

1] Iron-fe [ferrum]
2] Sodium-Na [Natrium]
3] Potassium-K [Kalium]

Question 12

What is Molecular mass of a substance ?

Answer 12

It is the sum of the atomic masses of all the atoms in a molecule of the substance.