Basics of Chemistry

Basics of Chemistry Worksheet-4

1. What is the center part of an atom called?

(a) element        (b) proton          (c) nucleus        (d) electron

2. What is the positively charged particle in the nucleus?

(a) electron       (b) proton          (c) neutrons      (d) orbit

Basics of Chemistry Worksheet-5

1. What is the negatively charged particle that orbits around the nucleus?

(a) electron       (b) proton          (c) neutron        (d) core

2. All atoms have an equal number of _______.

(a) electrons and nucleus            (b) electrons and neutrons

(c) neutrons and protons            (d) electrons and protons

3. Which of the following sentences describes difference between chemical and physical changes?

(a) A chemical change needs energy. A physical change needs heat.

(b) A chemical change is easy. A physical change is hard.