Atomic Number and Atomic Mass

What element is this?

• Helium

• Oxygen

• Carbon

• Nitrogen

Answer explanation

Carbon has 6 PROTONS. The number of protons CAN NEVER CHANGE. IF IT BECOMES 5 PROTONS IT IS NOT CARBON. IF IT IS 6 PROTONS IT IS NOT CARBON. CARBON IS 6 PROTONS.

Carbon has 6 Protons. What is its TOTAL WEIGHT? In science, weight is called MASS. Look at the square from the periodic table on the picture to find the MASS.

• 6 Atomic Mass Units (AMU)

• 12.68

• 12.01

• 18.01

Answer explanation

THE TOTAL WEIGHT (MASS) IS 12.01. THERE ARE 6 PROTONS. EACH PROTON WEIGHS 1.

What is missing in the Nucleus shown? Inside the nucleus are two types of particles: Protons and _________.

• Mecatrons.

• Cartrons.

• Scantrons.

• Neutrons.

Answer explanation

THE CARBON NUCLEUS HAS 6 PROTONS AND ALSO HAS NEUTRONS. THE TOTAL WEIGHT OF THE CARBON ATOM IS 12.01 AMU.

The Neutrons are missing in the green Circle. How many Neutrons are there in the Carbon Atom?

• 12.01

• 6

• 6.99

• 6.89

Answer explanation

6 PROTONS + 6 NEUTRONS = TOTAL WEIGHT OF THE CARBON ATOM (12.01)

(WE WIIL LEARN ABOUT THE .01 LATER)

HOW MANY PROTONS DOES OXYGEN HAVE?

• 15.99

• 16

• 8

• 6

Answer explanation

OXYGEN HAS 8 PROTONS (YOU CAN COUNT SQUARES TO OXYGEN IN THE 2ND ROW (PERIOD).

What does the Oxygen atom weight (MASS)?

• 8 protons

• 8 Scantrons

• 15.99 Atomic Mass Units (AMU)

• 8 AMU

Answer explanation

The Oxygen atom has a weight of 15.99 Atomic Mass Units.

How many Neutrons does oxygen have? Complete the following: 8 protons + ? Neutrons = Total Atomic Weight (15.99)

• 8 Protons

• 8 Scantrons

• 8 Neutrons

• 16 Atomic Mass Units.

Answer explanation

There are 8 Protons and 8 Neutrons . The Atomic Weight (Mass) = 15.99 (or 16)

What is wrong with this picture?

• The Atomic Number (the number of Neutrons) should be 5

• The Atomic Mass (the number of Protons and Neutrons ) should be 25

• The Atomic Number (the number of Protons) should be 3.

• The symbol for Lithium is LI

Answer explanation

The Atomic Number (the number of Protons) is 3.

What is wrong with this picture?

• 1. 12.01 is the Atomic Number for Carbon

• 7 is the Atomic Mass (weight) of Carbon

• Carbon's Atomic Number is 6. If it were 7, this element would be Nitrogen. An Atomic Number does not change.

• The Atomic Mass of Carbon is 12.01 +7 =19..01. The Atomic Mass is the sum of the Atomic Number and the Atomic Mass.

A Neutral Oxygen atom has 8 Protons, 8 Electrons and 8 Neutrons. What is its Atomic Mass?

• 8

• 16

• 24

• 32