UNIT 1 : Atomic Structure

Question 1

what is an element?

Answer 1

An element is the simplest type of chemical substance made up of one type of atom

Question 2

How are the elements listed?

Answer 2

In a chart called the periodic table in order of increasing atomic number

Question 3

what are groups in the periodic table?

Answer 3

Groups are a column in the periodic table

Question 4

what are the different groups in the periodic table?

Answer 4

• Group 1 called Alkali Metals
• Group 7 called Halogens
• Group 8 called Noble gases
• Block between group 2 and 3 are called transition metals

Question 5

what similarities do elements in the same group have? why?

Answer 5

They show similar chemical properties because elements in the same group have the same number of outer electrons. ( which is same as the group number)

Question 6

what are all the different ways elements can be classified?

Answer 6

• naturally occurring/ man-made
• solid/ liquid/ gas
• metal/ non-metal

Question 7

where are all the different classification of elements placed on the periodic table?

Answer 7

_ metals are on left of zig-zag line

- non-metals on right side of zig-zag line

Question 8

what elements are liquid at room temperature?

Answer 8

mercury and bromine

Question 9

what are compounds?

Answer 9

different elements which chemically join together to form compounds

Question 10

what is a mixture?

Answer 10

when substances mix together without a chemical reaction taking place

Question 11

what do compounds ending in -ide contain?

Answer 11

Contain only two elements

Question 12

what do compounds ending in -ate -ite contain?

Answer 12

contain more than two elements, one which is oxygen

Question 13

what are the exceptions for the compound ending rule?

Answer 13

• hydroxide = ‘anything’+hydrogen+oxygen

- cyanide= ‘anything’+ carbon+nitrogen

Question 14

what is at the centre of an atom?

Answer 14

• core called nucleus

Question 15

where are protons found?
what charge do they have?
what is their mass?

Answer 15

• nucleus
• one positive charge
• 1 amu

Question 16

where are neutrons found?
what charge do they have?
what is their mass?

Answer 16

• nucleus
• no charge, neutral
• 1 amu

Question 17

where are electrons found?
what charge do they have?
what is their mass?

Answer 17

• move outside the nucleus
• one negative charge
• No mass

Question 18

why are atoms electrically uncharged?

Answer 18

An atom is neutral because the number of protons is equal to the number of electrons

Question 19

what does the atomic number mean?

Answer 19

number of protons ( also gives number of electrons since equal and opposite charge to protons)

Question 20

how do u work out mass number?

Answer 20

protons+neutrons

Question 21

how do u work out number of neutrons?

Answer 21

mass number-protons

Question 22

how do u work out number of protons?

Answer 22

equal to atomic number

Question 23

how do you work out the number of electrons?

Answer 23

equal to number of protons ( in a neutral atom)

Question 24

how do you work out atomic number?

Answer 24

see periodic table

Question 25

How are electrons arranged?

Answer 25

Arranged in shells ( energy levels)

Question 26

How many electrons can each shell hold?

Answer 26

• 1st shell = 2 electrons
• 2nd shell = 8 electrons
• 3rd shell = 8 electrons ( for first 20 elements)

Question 27

what is the nuclide notation?

Answer 27

The atomic number and mass number written with the symbol of the element

Question 28

35
Cl what do each parts represent?
17

Answer 28

35 = mass number
17 = atomic number
cl = symbol of element

Question 29

what are isotopes?

Answer 29

Atoms with the same atomic number but different mass numbers

Question 30

what are the similarities and differences of isotopes of one element?

Answer 30

• same atomic number
• same number of protons
• different mass number
• different number of neutrons

Question 31

what is relative atomic mass?

Answer 31

The average mass of all the atoms of an element