Question

1. complete the table

particle	location of particle	charge on particle	mass of particle
	nucleus
		positive

1. which particle in question 9 above is used to differentiate atoms? and what is the number of this particle called

10.a group of atoms having the same number of protons in its nucleus is called
11.mass number is calculated by adding number of and

1. complete this table by filling - in. the atom is neutral. (for name of element, use the periodic table)

	proton	electrons	neutrons	atomic number	atomic mass	name of element
2		9	11
3				15	32
4			8			nitrogen

Explanation:

Step1: Recall atomic - particle properties

For question 8:

• Electron: Location is outside the nucleus, charge is negative, mass is approximately 0 amu.
• Neutron: Location is in the nucleus, charge is neutral, mass is approximately 1 amu.
• Proton: Location is in the nucleus, charge is positive, mass is approximately 1 amu.

The completed table for question 8:

Particle	Location of particle	Charge on particle	Mass of particle
Neutron	Nucleus	Neutral	1 amu
Proton	Nucleus	Positive	1 amu

Step2: Answer question 9

Protons are used to differentiate atoms. The number of protons is called the atomic number.

Step3: Answer question 10

A group of atoms having the same number of protons in its nucleus is called an element.

Step4: Answer question 11

Mass number is calculated by adding the number of protons and neutrons.

Step5: Complete table for question 12

• For row 1: In a neutral atom, number of electrons = number of protons = 4. Atomic number = number of protons = 4. Atomic mass = number of protons+number of neutrons = 4 + 5=9. The element with atomic number 4 is Beryllium.
• For row 2: In a neutral atom, number of protons = number of electrons = 9. Atomic number = 9. Atomic mass = number of protons+number of neutrons = 9+11 = 20. The element with atomic number 9 is Fluorine.
• For row 3: Atomic number = 15, so number of protons = 15. In a neutral atom, number of electrons = number of protons = 15. Number of neutrons = Atomic mass - number of protons=32 - 15 = 17. The element with atomic number 15 is Phosphorus.
• For row 4: For nitrogen, atomic number = 7, so number of protons = 7. In a neutral atom, number of electrons = number of protons = 7. Atomic mass is approximately 14 (common isotope), number of neutrons = Atomic mass - number of protons=14 - 7 = 7.

The completed table for question 12:

	proton	electrons	neutrons	Atomic number	Atomic mass	Name of element
2	9	9	11	9	20	Fluorine
3	15	15	17	15	32	Phosphorus
4	7	7	7	7	14	Nitrogen

Answer:

1. See completed table above.
2. Protons; Atomic number
3. Element
4. Protons; Neutrons
5. See completed table above.