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Question 1

What is an atom?

Answer 1

the smallest unit of matter and is the smallest part of an element that can exit (only one)

Question 2

What is an element?

Answer 2

a substance made from one type of atom
- all listed in periodic table - about 100

Question 3

What determines the element?

Answer 3

The number of protons/ atomic number

Question 4

What is the atomic or mass number?

Answer 4

• Small number = atomic number (number of protons and electrons)
• Bigger number = mass number (sum of neutrons and protons)

Question 5

What is inside the nucleus and what are their charges?

Answer 5

Protons - positive (relative mass of 1)
Neutrons - neutral (relative mass of 1)

Question 6

What orbits around the nucleus in shells?

Answer 6

Electrons - negative charge (has relative mass of 0- no mass)

Question 7

Why do atoms have no overall charge?

Answer 7

protons have positive, electrons have negative charge – these 2 are equal to each other so cancel each other

Question 8

What is an ion?

Answer 8

when atoms lose/gain electrons the charges of protons and electrons will no longer be equal and the atom overall charge will be changed. == a charged atom/molecule

Question 9

How can you work out ions charge?

Answer 9

• If an atom loses 1 electron, it becomes 1+ ion
• If an atom gains 1 electron, it becomes 1- ion
  -atoms lose/gain electrons to have full outer shells - to become stable

Question 10

What is an isotope?

Answer 10

(same atomic num but diff mass number)
- isotopes are different forms of the same element - that have same number of protons but different number of neutrons
ex: carbon - 12, carbon - 13

Question 11

What is the relative atomic mass?

Answer 11

-different isotopes have diff masses, so we need to work out average mass of all isotopes that make up an element

Question 12

How to work out relative atomic mass (Ar)?

Answer 12

sum of abundance of all isotopes

Question 13

Example of relative atomic mass:

Answer 13

• copper has 2 stable isotopes:
  1) copper - 63 (mass num) and abundance of 69.2%
  2) copper - 65 (mass num) and abundance of 30.8%
  so:
  (69.2 x 63) + (30.8 x 65) divided by (69.2+30.8)
  = Ar = 63.6169

Question 14

What is the abundance in the relative atomic mass?

Answer 14

How common the isotope is
– its in a percentage that you need to multiply by the mass number of isotope

Question 15

What is a molecule?

Answer 15

2 or more atoms held together by chemical bonds - can contain different elements

Question 16

What is a compound?

Answer 16

2 or more DIFFERENT elements held together by chemical bonds - always found in fixed proportions + difficult to separate them (have to do chemical reactions)
- the properties of compounds are diff from properties of elements they’re from

Question 17

Molecules and compounds?

Answer 17

• all compounds are molecules
• not all molecules are compounds
• molecules are just any 2 or more elements chemically combined
• compounds are two different elements chemically combined

Question 18

What is a mixture?

Answer 18

• consists of 2 or more elements that are not chemically combined together - they haven’t reacted they’ve just been physically put together – to separate, need to use physical methods (filtration/crystallisation/distillation)

Question 19

Metals form which ions?

Answer 19

• more on the periodic table (on left side)
• form positive ions (1+ ions)

Question 20

Non metals form which ions?

Answer 20

• on right side of periodic table
• form negative ions (1- ions)

Question 21

Physical properties of metals?

Answer 21

• very strong due to metallic bonds
• shiny
• malleable - can be bent without snapping
• good conductors of heat + electricity
• high melting and boiling point
• high density (weight)

Question 22

Physical properties of non-metals?

Answer 22

• dull in colour
• brittle - break easily
• low boiling and melting point
  low conductors of heat and electricity
• lower density (weight)

Question 23

Transition metals?

Answer 23

• in the middle of the periodic table
• have the same properties as metals
• can form more than 1 ion
• make good catalysts (speed up chemical reactions without being used up)

Question 24

What are the columns on the periodic table called?

Answer 24

Groups

Question 25

What are the rows on the periodic table called?

Answer 25

Periods

Question 26

Are elements in the same group similar or different?

Answer 26

• may have similar chemical properties
• because they have same number of electrons on outer shells – group 2 have 2 electrons on outer shell/ group 1 has 1 electron

Question 27

Who created the periodic table?

Answer 27

Mendeleev

Question 28

What is similar about elements in same periods/rows?

Answer 28

• have same number of shells

Question 29

The majority of elements in periodic table are?

Answer 29

Metals

Question 30

Elements that react to form positive ions are?

Answer 30

Metals

Question 31

Elements that react to form negative ions are?

Answer 31

Non-metals