C1 - Atomic Structure and the Periodic Table

Question 1

Element

Answer 1

A substance made of only one kind of atom.

Question 2

Compound

Answer 2

A substance made of more than one kind of atom, chemically bonded.

Question 3

Mixture

Answer 3

A mixture of substances, not joined together.

Question 4

Empirical Formula

Answer 4

The simplest ratio of atoms in each element or compound.

Question 5

What particles are contained in the nucleus of an atom?

Answer 5

Protons and Neutrons

Question 6

What charge do electrons have?

Answer 6

Negative Charge

Question 7

Isotope

Answer 7

Different forms of an element, with different numbers of neutrons.

Question 8

Are the reactivities of isotopes different?

Answer 8

No, as the electron structure remains the same.

Question 9

What is atomic number?

Answer 9

The number of protons that an atom has. This is what defines the element of the atom.

Question 10

What particle in an atom defines its reactivity?

Answer 10

Electrons

Question 11

What is Atomic Mass?

Answer 11

The total mass of an atom. Each proton and neutron has a mass of 1, while an electron has a mass of 1/1836, but is usually ignored, as the value is very small.

Question 12

Different isotopes of an element will have different…

Answer 12

Atomic mass

Question 13

What is Relative Atomic Mass?

Answer 13

The average mass of atoms takes account of the abundances of the isotopes of the element. The mass is compared to 1/12th of the mass of a Carbon-12 atom.

Question 14

How is relative atomic mass calculated?

Answer 14

By multiplying the mass of every isotope by its percentage abundancy, adding them all together, and dividing by 100.

Question 15

What is electron configuration?

Answer 15

The way the electrons are placed throughout an atom.

Question 16

Where are electrons on an atom?

Answer 16

They are based in energy levels, or “shells” which orbit the nucleus.

Question 17

Which shell is filled first by electrons in an atom?

Answer 17

The innermost shell.

Question 18

What is the electron structure of magnesium?

Answer 18

2,8,2

Question 19

The ….. electrons an atom has in its outer shell, the more reactive it is.

Answer 19

Less

Question 20

Why do atoms in the same group have similar reactivities?

Answer 20

Because the number of electrons in their outer shell is the same.

Question 21

Why is caesium more reactive that lithium?

Answer 21

Because the more shells there are, the harder it is for the electrostatic forces of the nucleus to attract the electrons, so the easier it is for the electrons to be lost.

Question 22

The group number of an element is the number of ……………….

Answer 22

Electrons that it has in its outer shell.

Question 23

The period number of an element is the number of ………….. it has.

Answer 23

Electron shells

Question 24

What are ions?

Answer 24

Ions are atoms with a charge.

Question 25

What are positive ions called?

Answer 25

Cations.

Question 26

What are negative ions called?

Answer 26

Anions.

Question 27

What types of elements form cations?

Answer 27

Metals and hydrogen form cations by losing the electrons in their outermost shell.

Question 28

What types of elements form anions?

Answer 28

Non-metals and hydrogen form anions by gaining electrons to fill their outermost shell.

Question 29

Why do atoms form ions?

Answer 29

To fill their outer shell and become stable like the Noble gases.

Question 30

What happens when metals and non-metals react?

Answer 30

The metals lose the electrons in their outer shell, which are gained by the non-metals, filling their outer shell, making metal cations and non-metal anions. Because of their opposite charge, they are attracted together and form a large lattice.