Atomic Mass, Atomic Number and Isotope

What is the mass number of this atom?

• 4

• 5

• 9

• none of the above

Tags

NGSS.MS-PS1-1

Most of the mass of an atom is contained here.

• electron orbitals 

• nucleus

• shells

• atomic #

A phosphorus atom has 15 protons and 16 neutrons. What is the mass number?

• 15

• 16

• 31

• 1

An atom of argon has 18 protons and 22 neutrons. How many electrons does it have?

• 18

• 22

• 40

• 4

one of several forms of a single element, which contains the same number of protons, but different numbers of neutrons

• isotope

• ion

• orbital

• nucleus

an arrangement of the elements according to their atomic numbers so that elements with similar properties are in the same column and properties repeat from row to row

• Periodic Table of Elements

• Atomic Theory

• Isotopes

• Subatomic Particles

a unique number for each element that equals the number of protons in an atom of that element

• element name

• element symbol

• atomic number

• atomic mass

the mass of an atom, calculated by adding the number of protons and neutrons in the nucleus of the atom

• element name

• element symbol

• atomic number

• atomic mass

How many protons does this isotope of titanium have?

• 48

• 22

• 26

• 70

Tags

NGSS.MS-PS1-1

In a correctly written symbol what would be located in the "A" position?

• number of neutrons

• atomic number

• number of electrons 

• mass number