TEST 1

The nucleus of an atom is made up of which of the following combinations of particles?

• electrons and protons
• electrons and neutrons
• protons, electrons, and neutrons
• protons and neutrons

To which of the following is the atomic number of a given element equivalent?

• he number of protons in the nucleus
• the number of neutrons in the nucleus
• the sum of the protons and neutrons in the nucleus
• the number of electrons in the outer shells

Rutherford’s experiments involving the use of alpha particle beams directed onto thin metal foils demonstrated the existence of which of the following?

• neutron
• proton
• nucleus
• positron

What does the mass number of a nucleus indicate

• the number of neutrons present
• the number of protons present
• the average atomic mass of the element
• the number of neutrons and protons present

If there are 128 neutrons in Pb-210, how many neutrons are found in the nucleus of Pb-206?

• 122
• 124
• 126
• 130

What is the binding energy of a nucleus?

• the energy needed to remove one of the nucleons
• the average energy with which any nucleon is bound in the nucleus
• the energy released when nucleons bind together to form a stable nucleus
• the mass of the nucleus times c squared

As the number of protons in the nucleus increases, the repulsive force

• becomes stronger.
• weaker
• unchanged
• zero

Light nuclei are stable when the ratio of protons to neutrons is

• greater than 1.
• less than 1.
• equal to 1.
• equal to 2.

How does a radioactive isotope that emits an alpha particle change?

• Atomic number decreases by four
• Mass number decreases by four.
• Atomic number decreases by one.
• Mass number decreases by one.

Of the main types of radiation emitted from naturally radioactive isotopes, which is the most penetrating?

• alpha
• beta
• gamma
• positron