IGCSE: Atomic Structure: protons, neutrons, electrons and electronic structure

How do you calculate the number of electrons in a neutral atom?

The number of protons = the number of electrons for a neutral atom

How do you calculate the number of neutrons for a lithium?(⁷₃Li)

The top number - the bottom number=7-3=4 or The mass number - the proton number=7-3=4

What do the two numbers associated with lithium mean? ⁷₃Li

The top number is equal to the protons + neutrons=mass number=7 The bottom number is the number of protons=3

What are the two parts an atom can be divided into?

Nucleus and electron shells

Which particle is more important given that a hydrogen nucleus doesn't even need neutrons?

Protons

What particles which make up an atom are charged?

Protons and electrons

What particles give an atom most of their mass?

Protons and neutrons

What are the two particles which contribute most to the mass of an atom?

Protons and neutrons.

What sub-atomic particle which has a positive charge is fixed for each specific atom of an element?

Protons.

What needs to be present for an atom to be neutral?

Same number of positive protons and negative electrons.

Calcium has 20 electrons, what will its electron configuration be?

2.8.8.2

What is the mass of a protons and a neutron?

1

An element has the configuration 2,8,1. What group of the periodic table is it in?

1 (The group is equal to the number of electrons in the outer shell).

A neutral atom of an element has the configuration 2,8,1. How many protons does it have?

11 (For a neutral atom the number of positive protons will be equal to the number of negative electrons).

A neutral atom of an element has the configuration 2,8,1. How many electrons does it have?

11 (The sum of the electrons in each shell)

Which is the atomic mass number of an atom equal to? (¹²₆C)

12 (It is equal to the number of protons+ the number of neutrons).

What is the total number of protons and neutrons for the following? (¹²₆C)

12 (The number at the top is equal to the number of protons + the number of neutrons).

Which of the two numbers is the atomic mass number of carbon (¹²₆C)?

12 (The number at the top left is the atomic mass number).

How many neutrons does the following carbon atom have? (¹²₆C)

12 is the mass number (equal to the number of protons+ the number of neutrons), 6=the number of protons. The difference is the number of neutrons-->12-6=6

How many electrons will a potassium atom have given it has 19 protons and 20 neutrons?

19(The number of protons = the number of electrons for a neutral atom)

What is the maximum number of electrons found in the first electron shell for an atom?(Also the same as the number of elements in the first row of the periodic table)

2

How many protons does a helium atom have? (⁴₂He)

2 (The number at the bottom left is the number of protons which is called the atomic number).

Which of the two numbers is helium's atomic number? (⁴₂He)

2 (The number at the bottom left is where the atomic number is written).

How many electrons will a helium atom have given it has 2 protons?

2 (The number of protons = the number of electrons for a neutral atom).

Lithium has 3 electrons, what will its electron configuration be?

2.1

Carbon has 6 electrons, what will its electron configuration be?

2.4

Oxygen has 8 electrons, what will its electron configuration be?

2.6

Sodium has 11 electrons, what will its electron configuration be?

2.8.1

How many protons does lithium (⁷₃Li) have?

3 (The number at the bottom left is equal to the number of protons in an atom, also called the atomic number).

An element has the configuration 2,8,1. What period of the periodic table is it in?

3 (The period is equal to the number of electron shells (First shell with electrons is the one with 2, second shell with 8....).

How many electrons will a lithium atom have given it has 3 protons and 4 neutrons?

3(The number of protons = the number of electrons for a neutral atom).

An element has the configuration 2,8,4. What group of the periodic table is it in?

4 (The group is equal to the number of electrons in the outer shell).

An element has the configuration 2,8,8,2. What period of the periodic table is it in?

4 (The period is equal to the number of electron shells (First shell with electrons is the one with 2, second shell with 8....).

How many protons does carbon (¹²₆C) have?

6 (The number at the bottom left is equal to the number of protons in an atom, also called the atomic number).

Which of the two numbers is the atomic mass number of lithium (⁷₃Li)?

7 (The number at the top left is the atomic mass number).

What is the common maximum number of electrons found in the third electron shell for an atom?(Also the same as the number of elements in the third row of the periodic table)

8

What is the maximum number of electrons found in the second electron shell for an atom?(Also the same as the number of elements in the second row of the periodic table)

8

What particle has the opposite charge to that of a proton?

An electron

If you look at a periodic table there are two numbers associated with each element. What is the smallest number called? What is another term for this number?

Atomic number or proton number.

What sub-atomic particle which has very little mass can atoms gain or lose?

Electrons

What does the number 4 on following helium atom mean? ⁴He

Helium has a mass number of 4, which is equal to the number of particles in the nucleus (protons and neutrons).

What is the charge and mass of an electron?

It has a mass of 1 /2000 and a charge of -1

What is the charge and mass of a proton?

It has a mass of 1 and a charge of +1

What is the charge and mass of a neutron?

It has a mass of 1 and a charge of 0

What does the number 9 on the following mean ₉F?

It means there are 9 protons present.

An atom of the fluorine has no charge (it is neutral) how many electrons will it have? ₉F

It will have 9 negative electrons present to balance the 9 positive protons.

What number do you get if you sum the number of protons and neutrons for an atom?

Mass number

What term is used for the sum of protons and neutrons for an atom?

Mass number

What is the shorthand for an electron?

e⁻ or e

What is the shorthand for a neutron?

n⁰ or n

What are the two particles found in the nucleus?

protons and neutrons.

What is the shorthand for an proton?

p⁺ or p

How many protons, neutrons and electrons does the following atom have (⁴₂He)?

p⁺=2, e⁻=2,n=2

How many protons, neutrons and electrons does the following atom have (⁷₃Li)?

p⁺=3, e⁻=3, n=4

How many protons, neutrons and electrons does the following atom have (¹⁴₆C)?

p⁺=6, e⁻=6,n=8