Isotopes and Atomic Mass

Multiple Choice

Oxygen has 8 protons. What is oxygen's atomic number?

• 16
• 8
• 15.999
• 0

Multiple Choice

If a hydrogen atom has 1 proton, 1 electron, and 1 neutron, its atomic number is:

• 1
• 2
• 3

Multiple Choice

What is the atomic number of Fe? (click to see image)

• 26

• 55.845

• 56

• 30

Multiple Choice

Which subatomic particles contribute the most to the mass of an atom?

• Protons, Neutrons, Electrons
• Protons only
• Protons and Electrons
• Protons and Neutrons

Multiple Choice

Isotopes of an element have a different number of...

• Protons

• Neutrons

• Electrons

• Mass

Hotspot

Look at the avaerage atomic mass from the periodic table. Use it to predict the most common isotope of the following elements: