Atoms Ions Isotopes

The majority of an atom's mass comes from which particle(s)?

• Protons

• Protons + electrons

• Electrons

• Protons + neutrons

Which is true of the following beryllium atom?

• 4 protons and 9 neutrons

• 5 neutrons and 4 electrons

• 9 protons and 4 neutrons

• 4 protons and 2 electrons

Tags

NGSS.MS-PS1-1

The number of protons + neutrons in the nucleus is referred to as what?

• Atomic number

• Atomic mass

• Mass number

• Isotope number

Which subatomic particle is used to identify the atom, as it never changes?

• Protons

• Neutrons

• Electrons

An ion with a positive charge has __________.

• the same number of protons and electrons.

• lost a proton.

• lost an electron.

• gained an electron.

Which of the following describes a positive ion?

• 10 protons, 12 electrons

• 12 protons, 10 electrons

• 12 protons, 12 electrons

Which of the following describes a negative ion?

• 8 protons, 8 neutrons, 8 electrons

• 8 protons, 8 neutrons, 10 electrons

• 8 protons, 10 neutrons, 8 electrons

• 8 protons, 8 neutrons, 6 electrons

Tags

NGSS.MS-PS1-1

What is the purpose of the neutrons?

• Identifies the element.

• Holds the nucleus together.

• Determines reactivity.

Which subatomic particles would repel away from each other?

• protons and neutrons

• protons and electrons

• electrons and electrons

• electrons and neutrons

Atomic mass is __________.

• a whole number

• protons + neutrons

• the mass found on the periodic table

• equal to the mass number of the most common isotope