Atomic Structure (APCh2)

Which part of the atom contains most of the mass?

• Electrons

• Nucleus

• Protons

• Neutrons

Tags

NGSS.HS-PS1-8

Determine the atomic number, mass number, number of protons, neutrons, and electrons for a neutral atom of potassium-39.

• Atomic # 19

  Mass # 39

  Protons 19

  Neutrons 20

  Electrons 19

• Atomic # 19

  Mass # 39.098

  Protons 19

  Neutrons 19

  Electrons 19

• Atomic # 39

  Mass # 19

  Protons 39

  Neutrons 19

  Electrons 39

• Atomic # 19

  Mass # 39.098

  Protons 19

  Neutrons 20

  Electrons 19

Tags

NGSS.MS-PS1-1

In a neutral atom what two subatomic particles are equal?

• Neutrons + Protons

• Electrons + Neutrons

• Protons + Electrons

How many neutrons are in carbon-14?

• 6

• 8

• 7

• 14

There are two naturally occuring isotopes of lithium, lithium-7 and lithium-6. If the average atomic mass is 6.941 which isotope is more abundant?

• Neither, same abundance

• Lithium-6

• Lithium-7

The table below gives the atomic mass and the abundance of the two naturally occurring isotopes of bromine.

Which numerical setup can be used to calculate the atomic mass of the element bromine?

• (78.92 u)(50.69) + (80.92 u)(49.31)

• (78.92 u)(49.31) + (80.92 u)(50.69)

• (78.92 u)(0.5069) + (80.92 u)(0.4931)

• (78.92 u)(0.4931) + (80.92 u)(0.5069)

Tags

NGSS.MS-PS1-1

If 75.0% of the isotopes of an element have a mass of 35.0 amu and 25.0% of the isotopes have a mass of 37.0 amu, what is the atomic mass of the element?

• 35.0 amu

• 36.0 amu

• 35.5 amu

• 37.0 amu

Tags

NGSS.MS-PS1-2

What does the number 84 in krypton-84 represent?

• the atomic number

• the mass number

• the sum of the protons and electrons

• twice the number of protons

Tags

NGSS.HS-PS1-8

Consider an element Z that has two naturally occurring isotopes with the following percent abundances: the isotope with a mass number of 22.0 is 65.0% abundant; the isotope with a mass number of 24.0 is 35.0% abundant. What is the average atomic mass for element Z?

• 19.9 amu

• 22.7 amu

• 23 amu

• 23.3 amu

Calculate the atomic mass of silicon. The three silicon isotopes have atomic mass and relative abundances of 27.9769 amu (92.2297%), 28.9765 amu (4.6832%) and 29.9738 amu (3.0872%).

• 28.0853 amu

• 25166.4483 amu

• 2808.5389 amu

• 28.0546 amu