topic 1- atomic structure and the periodic table

Question 1

what is the relative mass of a neutron?

Answer 1

1

Question 2

true or false: elements only contain atoms with the same number of protons

Answer 2

true

Question 3

define relative atomic mass

Answer 3

the average mass of an atom relative to the mass of one carbon-12 atom

Question 4

how similar are the properties of a compound to the elements it’s made from?

Answer 4

they are usually totally different

Question 5

give the formula for carbon dioxide

Answer 5

CO2

Question 6

give the formula for sodium carbonate

Answer 6

Na2CO3

Question 7

give the formula for hydrochloric acid

Answer 7

HCl

Question 8

balance the equation: Mg + O2 –> MgO

Answer 8

2Mg + O2 –> 2MgO

Question 9

balance the equation: H2SO4 + NaOH –> Na2SO4 + H2O

Answer 9

H2SO4 + 2NaOH –> Na2SO4 + 2H2)

Question 10

what is the difference between a compound and a mixture

Answer 10

compounds are atoms that are chemically joined, mixtures are not

Question 11

what is the name of the pattern of spots generated by paper chromatography

Answer 11

chromatograph

Question 12

give the name of a method used to separate an insoluble solid from a liquid

Answer 12

filtering

Question 13

describe how different substances are separated by fractional distillation

Answer 13

1) put your mixture in a flask and stick a fractionating column on top. then heat it
2) the different liquids will all have different boiling points so they will evaporate at different temperatures
3) the liquid with the lowest boiling point evaporates first. when the temperature on the thermometer matches the boiling point of this liquid, it will reach the top of the column
4) liquids with higher boiling points might also start to evaporate, but the column is cooler towards the top. so they will only get partway up before condensing and running back down towards the flask
5) when the first liquid has been collected, you raise the temperature until the next one reaches the top

Question 14

who demonstrated that the plum pudding model was wrong

Answer 14

ernest rutherford

Question 15

what did bohr’s nuclear model of the atom suggest

Answer 15

all of the electrons are contained in shells

Question 16

give the electronic configuration for helium

Answer 16

2

Question 17

give the electronic configuration for carbon

Answer 17

2, 4

Question 18

give the electronic configuration for sodium

Answer 18

2, 8, 1

Question 19

why did mendeleev leave his periodic table of elements

Answer 19

because he knew that there were elements we hadn’t found yet so he left space for them to be added in

Question 20

what name is given to the vertical columns in the periodic table

Answer 20

groups

Question 21

how are the group number and the number of the electrons in the outer shell of an element related

Answer 21

the number of the group is the same as the number of electrons in the outer shell of the element

Question 22

where are the nonmetals in the periodic table

Answer 22

on the right

Question 23

give three properties which are specific to transition metals

Answer 23

can have more than one ion, are colourful, they make good catalysts

Question 24

state three trends in group one elements as you go down the group

Answer 24

they get more reactive, lower melting/ boiling points, higher relative atomic mass

Question 25

state the products of the reaction between sodium and water

Answer 25

hydrogen gas and metal hydroxides

Question 26

state the differences between group one elements and transition metals in terms of hardness

Answer 26

group one metals are less hard

Question 27

state the differences between group one elements and transition metals in terms of reactivity

Answer 27

group one metals are more reactive

Question 28

state the differences between group one elements and transition metals in terms of melting points

Answer 28

group one metals have much lower melting points (except the transition metal mercury)

Question 29

how do the boiling points of halogens change as you go down the group

Answer 29

it increases

Question 30

how many atoms are in each molecule of a halogen

Answer 30

2

Question 31

what is the charge of the ions that halogens form when they react with metals

Answer 31

-1

Question 32

what is the trend in boiling point as you go down group 0

Answer 32

it increases