C1 - Atomic Structure & The Periodic Table

Question 1

What is an atom?

Answer 1

The smallest particle of an element that can exist.

Question 2

What is an element?

Answer 2

A substance that is made up of one type of atom only.

Question 3

What is a compound?

Answer 3

A substance made from atoms of different elements chemically bonded together, in fixed proportion.

Question 4

What is a mixture?

Answer 4

Two or more substances combined together but not held together by a chemical bond.

Question 5

What is an isotope?

Answer 5

Form of an element with atoms that have the same number of protons but a different number of neutrons

Question 6

What is relative atomic mass?

What is the equation for RAM?

Answer 6

The average mass of the atoms in an element.

(Mass 1 x % 1) + (mass 2 x % 2)
———————————————
100

Question 7

What is the radius of an atom?

Answer 7

About 1x10⁻¹⁰ metres

Question 8

How large is the nucleus compared to the atom?

Answer 8

Less than 1/10,000 of the atom’s radius

Question 9

What is the overall charge of an atom? Why?

Answer 9

0 because the number of protons and electrons is always equal.

Question 10

What is the relative charge and relative mass of a proton?

Answer 10

Charge: +1
Mass: 1

Question 11

What is the relative charge and relative mass of a neutron?

Answer 11

Charge: 0
Mass: 1

Question 12

What is the relative charge and relative mass of a electron?

Answer 12

Charge: -1
Mass: almost 0 (1/1836)

Question 13

What does filtration do?

What is an example of filtration?

Answer 13

Separates insoluble solid from liquid

Sand and water

Question 14

What does crystallisation do?

What is an example of crystallisation?

Answer 14

Separates soluble solid from liquid

Salt and water

Question 15

What does simple distillation do?

What is an example of simple distillation?

Answer 15

Separates 2 liquids OR soluble solid from liquid when collecting both

Ethanol and water

Question 16

What does fractional distillation do?

What is an example of fractional distillation?

Answer 16

Separates multiple liquids with different boiling points

Crude oil

Question 17

Paper chromatography

Question 18

Simple distillation practical

Question 19

Fractional distillation practical

Question 20

What is the timeline of the history of the atom?

Answer 20

1800’s - Hard spheres (John Dalton)

1897 - JJ Thompson created the plum pudding model

1909 - Ernest Rutherford conducted the alpha particle scattering experiment

1911 - Ernest Rutherford created the nuclear model of the atom

1913 - Niels Bohr

1932 - James Chadwick discovered neutrons

Question 21

What was the plum pudding model?

Who created the plum pudding model?

Answer 21

Atoms were spheres of positive charge with tiny negative electrons stuck in them

J. J. Thomson (in 1897)

Question 22

What was the plum pudding model replaced with?

Answer 22

1911 - The nuclear model

• Most of the atom is empty space
• There is a concentrated mass in the middle - nucleus
• Atoms contain positively charged particles (protons) in the middle

Question 23

What was the alpha scattering experiment?

Answer 23

• Positively charged alpha particles were fired at a thin sheet of gold foil
• Most went straight through but a few scattered

Question 24

What was the nuclear model replaced with?

Answer 24

1913 - The Bohr model

Electrons are in fixed shells around the nucleus.

Question 25

What was the Bohr model replaced with?

Answer 25

The current atomic model

1932 - James Chadwick discovered neutrons and created a model closest to the current atomic model

Question 26

What are the electron shell rules?

Answer 26

• electrons always occupy shells
• the lowest energy levels (closest to nucleus) are always filled first
• there is a limited number of elctrons allowed in each shell - 2,8,8
• most atoms don’t have full outer shells, which makes them likely to react to fill it

Question 27

What is the timeline of the development of the periodic table?

Answer 27

1800’s - Elemnts were arranged by atomic weight

1864 - Newland’s theory: “law of octaves”
Every eighth element has similar
properties and reacts in a similar way.

1869 - Dmitri Mendeleev left gaps for element he predicted would be discovered

Elements are arranged by increasing atomic number (mass)

Question 28

How did Mendeleev arrange the elements?

Why did Mendeleev leave gaps in his periodic table?

Answer 28

By increasing atomic number (mass) instead of increasing atomic weight.

Mendeleev leave gaps in his periodic table because he correctly predicted some elements had not been discovered.

Question 29

1) What does the group number of an element tell you?

2) What does the period an element is in tell you?

Answer 29

1) The number of electrons in the outer shell

2) The number of shells

Question 30

What is group 1 on the periodic table?

&

What happens as you move down the group?

Answer 30

Alkali metals: metals that produce alkaline solution when they react with water.
They are reactive and soft metals.

reactivity increases, lower melting & boiling points, and higher relative atomic masses

Question 31

What is group 7 on the periodic table called?

&

What happens as you move down the group?

Answer 31

Halogens: non-metals with coloured vapours

Become less reactive, higher melting & boiling points, and higher relative atomic masses

Question 32

What is group 0 on the periodic table called?

&

What happens as you move down the group?

Answer 32

Noble gases: inert and colourless gases

The boiling points increase as you move down because there are more electrons in each atom (so there are greater intermolecular forces between them)