TOPIC C1- ATOMIC STRUCTURE AND THE PERIODIC TABLE

Question 1

atoms contain

Answer 1

-protons
-neutrons
-electrons

Question 2

the nucleus of an atom

Answer 2

-in the middle of an atom
-contains protons and neutrons
-positive charge because of protons
-whole mass is concentrated

Question 3

the electrons of an atom

Answer 3

-move around the nucleus in electron shells
-negatively charged and tiny
-volume determines the size
-virtually no mass

Question 4

how are atoms neutral

Answer 4

-they have no charge
-because they have the same number of protons and electrons

Question 5

what does the top number of a element tell you

Answer 5

-its mass number
(the number of protons and neutrons in the atom)

Question 6

atomic number

Answer 6

bottom number
the number of neutrons, subtract the atomic number from the mass number

Question 7

what is an element

Answer 7

a substance made up of atoms that all have the same number of protons in their nucleus

Question 8

definiton of isotope

Answer 8

different forms of the same element that have the same number of protons but different numbers of neutrons

Question 9

relative atomic mass formula

Answer 9

sum of (isotope abundace x isotope mass number)
DIVIDED BY——–
sum of abundance of all isotopes

Question 10

atoms join together to make

Answer 10

compounds

Question 11

symbol equations need to be

Answer 11

balanced
-same number of atoms on both sides
-can only put numbers infront of them

Question 11

whats a compound

Answer 11

-substances formed from 2 or more elements

Question 12

how can mixtures be seperated

Answer 12

by physical methods e.g filtration, crystallisation

Question 13

explain paper chromatography

Answer 13

1.draw a line near the bottom of a sheet of filter paper USE PENCIL as theyre insoluble
2. add a spot of ink to the line and place the sheet in a beaker of solvent
3. solvent depends on whats been tested and some compounds dissolve well in water, but sometimes ethanol is needed
4. make sure ink isnt touching the solvent, prevents dissolving
5. lid ontop of container to stop the solvent
6. solvent seeps up the paper, carrying ink
7. each dye moves up the paper at different rates and spread out
8.

Question 14

what does it mean in chromotography if any of the inks stay on the baseline

Answer 14

-they are insoluble

Question 15

what do you use fractional distillation for

Answer 15

to seperate mixtures of liquids

Question 16

in fractional distillation which liquid will evaporate first

Answer 16

-the one with the lowest boiling point

Question 17

who described atoms as solid spheres in the 19th century

Answer 17

John Dalton
-they were different spheres made up the different elements

Question 18

who created the theory of the plum pudding model

Answer 18

J J Thompson
-atom as a ball of positive charge with electrons stuck in it
-he concluded from experiments that atoms werent solid spheres

Question 19

who proved the plum pudding model wrong

Answer 19

-Ernest Rutherfood

Question 20

explain Rutherfords further ideas

Answer 20

-showed that the nucleus can be divided into smaller particles that have the same charge as hydrogen nucleus
-particles named protons

Question 21

state the rules of electron shells

Answer 21

1st shell- 2electrons
2nd shell- 8electrons
3rd shell- 8electrons
-in most atoms the outer shell is not fill and this makes the atom want to react to fill it

Question 22

whats the electronic structure of nitrogen
atomic number 7

whats the electronic structure of magnesium
atomic number 12

Answer 22

• 2,5

-2,8,2

Question 23

explain Dmitiri Mendeleevs development of the periodic table

Answer 23

-in 1869 he took** 50**known elements and arranged them into his table of elements, with various gaps
-he put elements mainly in order of **atomic weight **

Question 24

why did mendeleev leave gaps in his table

Answer 24

-to make sure elements with similar properties stayed in the same groups -some gaps indicated the existence of undiscovered elements and allowed him to predict their properties -when found they fit the pattern

Question 25

what made mendeleevs decision right to not place elements in a strict order of atomic weight

Answer 25

the discovery of isotopes

Question 26

how are elements laid out in the periodic table

Answer 26

-in order of increasing atomic (proton) number means theres repeating patterns in the properties of elements

Question 27

state where metals and non metals are found

Answer 27

-metals on the left -non metals on the right

Question 28

elements with similar properties form ... verticle columns are called

Answer 28

columns groups

Question 29

what does the group number tell you

Answer 29

how many electrons there are in the outer shell except group 0, heliumm has 2in outer shell -elements in the same group react in simalr ways -G1 elements react vigorously as you go down -G7 reacctivity decreases as you go down

Question 30

properties of metals

Answer 30

-strong -malleable -good conductors of heat and electricity -high boiling and melting points

Question 31

properties of non metals

Answer 31

-dont have metallic bonding -dull looking -brittle bad conductors of electricity -low density

Question 32

state what the following are known as -G1 ELEMENTS -G7 ELEMENTS G0 ELEMENTS

Answer 32

1- alkali metals 7-halogens 0-noble gases j

Question 33

# stat properties of group1 elements

Answer 33

-soft and have low density TRENDS as you go down -increasing reactivity -low melting and boiling points -high relative atomic mass

Question 34

state what happens when group1 elements are put in water +with chlroine

Answer 34

-react very vigorously -tend to float and fizz -produce hydrogen -form hydroxides that dissolve in water to give alkaline solutions -produces a salt, and metals react vigorously when heated in chlorine gas to form white salts -as you go down the group, reactions get more vigorous

Question 35

how do g1 metals react with oxygen

Answer 35

-react with oxygen to form a metal oxide -lithium reacts to form lithium oxide -potassium goes to potassium peroxide

Question 36

the halogens are all ----- with coloured vapours * fluorine * chlroine * bromine * iodine

Answer 36

-fluorine, very reactive, posinous yellow gas * chlroine, fairly reactive, posinous green gas * bromine, dense red-brown liquid * iodine, dark grey solid/ purple vapour

Question 37

state the trends in group 7 AS YOU GO DOWN -become more/less reactive -have higher/lower boiling and melting points -have high/low relative mases

Answer 37

-become less reactive as its harder to gain an extra electron -higher melting and boiling points -high relative atomic mass

Question 38

can halogens form molecular compounds, if so how

Answer 38

-they SHARE electrons via convalent bonding -with other metals -to achieve a full outer shell

Question 39

what type of ionic bond do halogens form

Answer 39

1-ions called halides

Question 40

group 0 characteristics

Answer 40

-8electrons in outershell -colourless gases at room temp -monatomic gases, not bonded -non flammable

Question 41

patterns in the properties

Answer 41

-boiling points increase as you move down -increasing relative atomic mass -increase in number of electrons in each atom leads to greater intermolecular forces