Topic 2

Question 1

What is an atom?

Answer 1

The smallest particle of a chemical element that can exist.

Question 2

What is the structure of an atom?

Answer 2

Atoms consist of a nucleus containing protons and neutrons, surrounded by electrons in shells. The numbers of subatomic particles in an atom can be calculated from its atomic number and mass number.

Question 3

What is a subatomic particle?

Answer 3

A Subatomic particle is nothing but a particle which is smaller than an atom in size. Typically, an atom can be broken down into three subatomic particles, namely: protons, electrons, and neutrons.

Question 4

Define an element?

Answer 4

each of more than one hundred substances that cannot be chemically interconverted or broken down into simpler substances and are primary constituents of matter. Each element is distinguished by its atomic number, for example the number of protons in the nuclei of its atoms.

Question 5

How does technology increase our understanding of the atom?

Answer 5

Although atoms are too small to be seen with our eyes, scientists have long had indirect evidence for the existence of atoms. We can now use the world’s most powerful scanning tunneling microscopes to “see” the magnified images of atoms and to study surface reaction sites on an atom-by-atom basis.