Atoms: Mid Semester Review

Element Keys

100

This element has the symbol "S."

Sulfur

200

This is the atomic number of Carbon.

(You may use the periodic table!)

6

300

This is the atomic mass of Oxygen. 

(Use the periodic table!)

16

400

This is the atomic mass of Boron.

(Use the periodic table!)

10.81

500

This is the element symbol for sodium.

(Use the periodic table!)

Na

Sub-atomic Particles

100

This is the particle with a positive charge.

Proton

200

This is the formula for atomic mass.

Mass = protons + neutrons

300

This is the particle with a negative charge.

Electron

400

This is the particle with a neutral charge.

Neutron

500

This is the formula for finding the net charge of an atom.

Charge = protons - electrons

Isotopes

100

What is the correct formula to find the number of neutrons in an atom?

Neutrons = atomic mass - protons (atomic #)

200

An isotope has a different number of...

Neutrons

300

Hydrogen has the atomic number 1. How many neutrons would Hydrogen-2 have?

1

400

Titanium has the atomic number 22. How many neutrons would Titanium-47 have?

25

500

How many neutrons does Carbon-14 have?

8

Ions

100

This is the formula for the net charge of an atom.

charge = protons - electrons

200

An ion of Beryllium has 4 protons and 5 electrons. What is its net charge?

NEGATIVE 1

300

An ion of Lithium has 3 protons and 2 electrons. What is its net charge?

+1

400

An ion of Carbon has 8 electrons. What is its net charge?

NEGATIVE 2

500

Silicon is atomic number 14, and has a relative mass of 28. How many electrons are in Si²⁺?

12 electrons