Homework #5 - Atomic Structure Day 1-5 Review

Which statement best explains why the nucleus is dense?

• It contains only electrons

• It contains nearly all of the atom’s mass

• It contains orbitals of electrons

• It is mostly empty space

Which particles are classified as nucleons?

• Protons only

• Neutrons only

• Protons and neutrons

• Protons and electrons

Tags

NGSS.HS-PS1-8

Which subatomic particle determines the identity of an element?

• Proton

• Neutron

• Electron

• Mass number

Which statement correctly describes electrons?

• They are found in orbitals

• They have a mass of about 1 u

• They have a positive charge

• They are found in the nucleus

Which part of an atom is always positively charged?

• Nucleus

• Electron cloud

• Neutrons

• Orbitals

A neutral atom has 15 protons, 16 neutrons, and 15 electrons. What is its overall charge?

• +15

• 0

• -1

• 31

Which isotope notation represents an atom of oxygen with 8 protons and 10 neutrons?

• O-8

• O-16

• O-18

• O-10

Tags

NGSS.HS-PS1-8

Which statement best compares the mass number and the atomic mass?

• Both are weighted averages

• Mass number is specific to one atom; atomic mass is an average across isotopes

• Mass number is always a decimal; atomic mass is a whole number

• They are always the same value

A chlorine atom has 17 protons, 18 neutrons, and 17 electrons. What is its mass number?

• 17

• 34.5

• 35

• 52

Which atom is an isotope of carbon-12?

• 6 protons, 6 neutrons

• 7 protons, 6 neutrons

• 6 protons, 8 neutrons

• 8 protons, 6 neutrons

Tags

NGSS.HS-PS1-8