Physics

Question 1

1Rutherford's gold-foil experiment showed that the atom

Easy

A. is solid throughout B. is made of electrons only C. has no charge D. has a small, dense, positive nucleus

Question 2

2A radioactive sample of 80 g has a half-life of 5 days. How much is left after 15 days?

Easy

A. 5 g B. 40 g C. 20 g D. 10 g

Question 3

3The charge on a neutron is

Easy

A. +2 B. +1 C. −1 D. zero

Question 4

4The mass number of an atom is the number of

Easy

A. neutrons only B. electrons only C. protons only D. protons plus neutrons

Question 5

5Isotopes of an element have the same number of

Easy

A. protons but different numbers of neutrons B. nucleons C. neutrons but different numbers of protons D. electrons and neutrons

Question 6

6An alpha particle is the same as

Easy

A. a photon B. a helium nucleus C. a neutron D. an electron

Question 7

7Which pair are isobars?

Hard

A. ¹⁴C and ¹⁴N B. ¹²C and ¹⁴C C. ¹⁶O and ¹⁸O D. ¹H and ²H

Question 8

8An atom of ²³Na₁₁ has how many neutrons?

Easy

A. 23 B. 12 C. 34 D. 11

Question 9

9The nucleus of an atom contains

Easy

A. electrons only B. protons and neutrons C. protons and electrons D. neutrons and electrons

Question 10

10The binding energy of a nucleus is the energy

Hard

A. stored in bonds between atoms B. of its electrons C. needed to separate it into its nucleons D. released by burning