Atomic Structure/Electrons Review

Which of the following isotopes has the largest number of neutrons?

• C-14

• N-15

• F-19

• O-16

If 98.93% of carbon atoms have a mass of 12 amu and 1.07% of carbon atoms have a mass of 13 amu, what is the average atomic mass of the element?

• 12.01

• 13.91

• 12.15

• 1201.07

What is the total number of valence electrons in a silicon atom?

• 14

• 8

• 4

• 6

Compared to carbon-14, nitrogen-15 has

• 1 more neutron

• 2 more valence electrons

• the same number of electrons

• the same number of neutrons

What is the mass of an atom with 35 protons and 44 neutrons?

• 35

• 44

• 79

• 9

What subatomic particles would you find in the nucleus of an atom?

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

Tags

NGSS.MS-PS1-1

If an atom has 12 positively charged subatomic particles, which of the following must it also have to be considered a neutral atom?

• 12 neutrons
• 12 electrons
• 12 protons
• 24 protons and neutrons

Tags

NGSS.MS-PS1-1

An element with a mass number of 11 and an atomic number of 5 has how many neutrons?

• 11
• 5
• 6
• 16

Tags

NGSS.MS-PS1-1

An atom has three isotopes. One has a percent abundance of 15% and a mass of 4 amu, one has a percent abundance of 10% and a mass of 5 amu and one has a percent abundance of 75% and a mass of 3 amu. The average atomic mass will be closest to

• 2 amu

• 3 amu

• 4 amu

• 5 amu

What are valence electrons?

• electrons on the first orbital always

• nucleus

• the outermost shell

• electrons on the outermost energy level