C1 Atomic Structure

Question 1

What is an element?

Answer 1

A substance made of one type of atom.

Question 2

What is a compound?

Answer 2

A substance made of two or more elements chemically combined.

Question 3

What is a mixture?

Answer 3

A substance made of two or more elements or compounds NOT chemically combined.

Question 4

What technique do you use to separate water from salt water?

Answer 4

Distillation. The water will evaporate and then condense. The salt will remain.

Question 5

What technique do you use to separate sand from salt water?

Answer 5

Filtration. The sand will be left in the filter (residue).

Question 6

How many atoms are in a molecule of CO2

Answer 6

3

Question 7

How many elements are in a molecule of CO2

Answer 7

2 (carbon and oxygen)

Question 8

Write the word equation for the reaction between iron and oxygen to make iron oxide.

Answer 8

Iron + oxygen –> iron oxide

Question 9

Balance this symbol equation. Mg + O2 –> MgO

Answer 9

2Mg + O2 –> 2 MgO

Question 10

Describe the plum pudding model of the atom.

Answer 10

A cloud of positive charge with small negatively charged electrons scattered in it.

Question 11

What two conclusions were made from the alpha particle scattering experiments.

Answer 11

The mass of an atom is concentrated in the centre (nucleus). The nucleus is charged.

Question 12

How did Bohr and Chadwick improve the atomic model?

Answer 12

Electron shells

Question 13

What is the radius of the atom?

Answer 13

0.1nm

Question 14

How big is radius of the nucleus compared to the radius of the atom?

Answer 14

1/10,000 times smaller

Question 15

What is 1nm in metres in standard form?

Answer 15

1 x 10-9 m

Question 16

What is the relative mass of protons, neutrons and electrons?

Answer 16

1,1,0

Question 17

What is the relative charge of protons, neutrons and electrons?

Answer 17

+1, 0 , -1

Question 18

What does the atomic number tell you about an atom?

Answer 18

The number of protons (which is equal to the number of electrons)

Question 19

What does the mass number tell you about an atom?

Answer 19

The total number of protons and neutrons.

Question 20

How many protons, neutrons and electrons are in sodium?

Answer 20

11, 12, 11

Question 21

How do atoms become ions?

Answer 21

Lose or gain electrons

Question 22

What is an isotope?

Answer 22

Same element, different number of neutrons

Question 23

How many electrons fit into the first, second and third electron shells?

Answer 23

2,8,8

Question 24

Why do elements in the same column of periodic table have similar chemical properties?

Answer 24

Same number of electrons in outer shell.