Periodic Table, Atomic Structure, Ions and Isotopes

When an atom loses a valence electron, it becomes a(n) _____________ ion.

• positive
• negative
• neutral
• polyatomic

Atoms of the same element must always have the same number of _________

• electrons
• neutrons
• isotopes
• protons

The __________ of an atom is the sum of the protons and neutrons in the nucleus of that atom.

• mass number
• atomic number 
• atomic weuight
• isotope weight

Tags

NGSS.HS-PS1-8

Two atoms of the same element but with different mass numbers are called________

• electrons
• isotopes
• variables
• electron cloud

How many protons are in an atom with an atomic number of 20, an atomic mass of 45, and a charge of +2?

• 20
• 10
• 2
• 18

Isotopes are elements with a different amount of

• protons
• neutrons
• electrons
• atoms

Tags

NGSS.HS-PS1-8

How many electrons are in an atom that has an atomic number of 34, an atomic mass of 74 and a charge of -2?

• 34
• 36
• 2
• 40

Tags

NGSS.HS-PS1-1

How many neutrons does the isotope of lithium have?

• 8
• 3
• 4
• 5

Tags

NGSS.HS-PS1-8

What particle provided the positive charge for an atom?

• proton 
• neutron
• electron
• nucleus

What do these isotopes of carbon all have in common?

• neutrons & mass number
• atomic number and neutrons
• atomic number and electrons
• protons, atomic number, and mass number