atomic structure and the periodic table

Question 1

number of protons determine what

Answer 1

it determines what the element is

Question 2

isotopes definition

Answer 2

isotopes are different forms of the same element that have the same number of protons but have a different number of neutrons

Question 3

equation for relative atomic mass

Answer 3

sum of isotope abundance x isotope mass/sum of abundance of all isotopes

Question 4

molecules meaning

Answer 4

2 or more atoms held together by chemical bonds

Question 5

compound meaning

Answer 5

2 or more different elements that are held together by chemical bonds

Question 6

mixture meaning

Answer 6

two or more substances not chemically bonded together

Question 7

what can mixtures be separated by

Answer 7

by physical processes such as filtration crystallisation simple distillation fractional distillation and chromatography these are physical processes and do not involve chemical reactions and no nee substances are made

Question 8

what is filtration

Answer 8

separating insoluble solids from liquids

Question 9

process of filtration

Answer 9

using filter paper and a funnel to filter the insoluble solid from the liquid

Question 10

process of evaporation

Answer 10

place solution in evaporating dish and heat with a bunsen burner while a tripod is separating it this will cause solvent to evaporate, crystals will start to form.
solvent will disappear leaving dry crystals as our solid

Question 11

what is thermal decomposition

Answer 11

some solids decomposing when heated

Question 12

process of crystallisation

Answer 12

solution placed in evaporation dish dish placed in a water bath. bunsen burner is heating the solvent. once crystals start to form we turn off bunsen burner and leave it to cool. as solution cools more crystals will form as solids are less soluble at cooler temps. next filter out the crystals from the solution using filter paper and funnel. then dry crystals.

Question 13

what is simple distillation

Answer 13

separating out a liquid from a solution

Question 14

process for simple distillation

Answer 14

have solution in a flask and have a bung seal the flask so no gas can escape. place thermometer through bung to measure temp. next condenser is connected to flask which has a continuous stream of cold water. with water being fed into water jacket at the bottom and coming out at the top. end of condenser have a beaker to capture pure liquid. finally heat flask with bunsen burner.

Question 15

what does the water jacket do on a condenser for simple distillation

Answer 15

it cools the vapour to a liquid

Question 16

what is fractional distillation

Answer 16

main technique for separating mixtures of liquids

Question 17

process for fractional distillation

Answer 17

flask with a bung. attached to a fractionating column which is attached to a condenser and at the end of the condenser is the beaker for the pure substance

Question 18

what is a fractionating column

Answer 18

it is full of little glass rods and is cooler at the top than at bottom.
the glass rods are used to condense the liquids which are not intended to be removed yet back into the flask.

Question 19

the plum pudding model and the differences between plum pudding model and nuclear model

Answer 19

the plum pudding model was discovered by jj thompson
it suggested that the atom is a ball of positive charge either negative electrons embedded in it.
nuclear model proposes the idea that there is a nucleus containing protons with electrons orbiting the nucleus in a cloud

Question 20

scattering experiment with sheet of gold

Answer 20

they shot alpha particles at the sheet of gold and some of the alpha particles either went through or they deflected away to the side . this proved jj theory wrong. rutherford proposed the idea of a nucleus and it contained the positive charge and the negative charge surrounding the nucleus.

Question 21

how to find number of protons and electrons on the periodic table

Answer 21

look at atomic number

Question 22

which group has a full outer shell on periodic table

Answer 22

group 0 the noble gases

Question 23

what did mendeleev do

Answer 23

he devised the periodic table and predicted new elements we hadn’t discovered yet.

Question 24

what is the group 7 elements called and how does there reacivity work

Answer 24

they get less reactive down the group and are called the halogens

Question 25

group 1 elements are called what and how does there reactivity work

Answer 25

they are called alkali metals and they get more reactive as you go down the group

Question 26

are metals positive or negative when they are ions

Answer 26

they form positive ions

Question 27

do metals lose or gain electrons

Answer 27

metals always lose electrons non metals gain electrons

Question 28

properties of metals and non metals

Answer 28

metals
mettalic bonding
malleable
conducters
high mp and bp
non metals
lower densities
low mp and bp
bad conducters
brittle
dull in colour

Question 29

properties of transition metals

Answer 29

can form more than one ion
they make very good catalysts

Question 30

properties of alkali metals (group 1 metas)

Answer 30

soft
low density
low mp
they are much more reactive and react vigorously with water
down the group they are more reactive
mp and bp decrease down the group

Question 31

properties of halogens

Answer 31

they exist as diatomic molecules (2 atoms)
which is a covalent bond
mp and bp decrease down the group
reactivity decreases down the group
when halogens react with metals they always end in identical e.g. fluoride

Question 32

displacement reactions

Answer 32

more reactive halogen will always displace less reactive ones

Question 33

group 0 properties

Answer 33

they are inert (dont react with other elements)
they are a colourless gas
they exist as single atoms
they are non flammable
there bp increases as you go down the group