Atoms and Isotopes

What does the atomic number of an element represent?

• The number of neutrons in an atom

• The number of protons in an atom

• The number of electrons in an atom

• The total number of protons and neutrons in the nucleus

How can the number of neutrons in an atom be calculated?

• By dividing the mass number by the atomic number

• By adding the atomic number to the mass number

• By subtracting the atomic number from the mass number

• By multiplying the atomic number with the mass number

What is true about isotopes of the same element?

• They have different numbers of electrons

• They have different atomic numbers

• They have different numbers of neutrons

• They have different numbers of protons

Tags

NGSS.HS-PS1-8

What charge does a positive ion have?

• It has gained electrons

• It has lost protons

• It has lost neutrons

• It has lost electrons

Tags

NGSS.MS-PS1-1

How many protons does an atom of lithium have?

• 11

• 7

• 4

• 3

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NGSS.MS-PS1-1

What is the mass number of an atom of lithium?

• 3

• 4

• 11

• 7

How many electrons does a sodium ion with a single positive charge have?

• 11

• 12

• 10

• 13

Tags

NGSS.MS-PS1-1

What is the overall charge of an oxide ion that has gained two electrons?

• 1 positive

• 1 negative

• 2 positive

• 2 negative

Tags

NGSS.MS-PS1-1

How many neutrons does the first isotope of chlorine contain?

• 20

• 18

• 22

• 17

Tags

NGSS.MS-PS1-1

What defines isotopes of the same element?

• Different atomic numbers

• Different numbers of electrons

• Same number of neutrons but different numbers of protons

• Same number of protons but different numbers of neutrons