Periodic Table

Question 1

How many elements are there
How many occur naturally

Answer 1

118
94

Question 2

What is the trend of G1
Reactiviy
Softness
Density
Melting+boiling

Answer 2

Increases down the group
Increases
Increases
Decreases

Question 3

Why are they called alkali metals

Answer 3

When reacted with water they form an alkaline solution

Question 4

Physical properties of alkali metals(2)

Answer 4

Relatively soft
Relatively low density and melting points
Tarnish?

Question 5

What is the general formula for G1+water

Answer 5

Metal+water=metal hydroxide+hydrogen gas

Question 6

What is lithiums reaction with water

Answer 6

It floats as it is less dense, there is effervescence and it moves around due to the hydrogen gas being given off
Dissolves to form aqueous solution of LiOH

Question 7

How does sodium react with water

Answer 7

Melts, floats, moves around on surface vigorously, effervescence and hydrogen gas
Dissolves to form NaOH

Question 8

How does potassium react with water

Answer 8

Enough heat is produced to light the hydrogen gas and a lilac flame is produced, hops around

Question 9

Explain the trend in reactivity of G1

Answer 9

The more easily the valence electron is lost the more reactive it is, the further down the group, the bigger the atom, the further away the electron is to the nucleus, the smaller the electrostatic attraction

Question 10

What was the first halogen to be discovered and where was it used

Answer 10

Flourine, in mineral fluorospar in ceramics

Question 11

How was chlorine extracted/discovered

Answer 11

From hcl

Question 12

How was bromine extracted/discovered

Answer 12

Bubbling chlorine gas through water sample

Question 13

How was iodine extracted/discovered

Answer 13

Burning seaweed and treating the ashes with sulfuric acid to produce a purple vapour

Question 14

How was astatine extracted/discovered

Answer 14

Bombarded bismuth with radiation

Question 15

Use of chlorine

Answer 15

To disinfect

Question 16

Use of bromine

Answer 16

To disinfect

Question 17

Use of Florine

Answer 17

To help medical drug enter cells

Question 18

Use of iodine

Answer 18

Prevent infection

Question 19

Use of satiating+all halogens

Answer 19

Energy efficient lamps

Question 20

Why is GVII called halogens

Answer 20

It means salt producing, when reacted with metals salts are produced

Question 21

What is the trend for colour in GVII + state fl,cl,br,I

Answer 21

Darkness decreases down
Yellow-green gas
Green gas
Red liquid
Dark purple solid

Question 22

Trend of GVII
Density
Melting points
Reactivity

Answer 22

Increase
Increase
Decrease

Question 23

Explain the reason for the trend in reactivity in GVII

Answer 23

Hal go gens have 7 valence electrons and react by attracting other electrons to fill their outer shell. As you descend down the group, the number of shells increase and the ability to attract the electrons decreases

Question 24

What happens When a more reactive element comes into contact with a less reactive element in a compound

Answer 24

A displacement reaction

Question 25

What is the trend of metallic characteristics across and down the periodic table Explain why these characteristics occur

Answer 25

The metallic characteristics decrease as you move right across a period, and increase as you move down a group. This is because non-metal atoms are more readily accepting to electroms to fill their valence shells.

Question 26

What are the physical properties of alkali metals

Answer 26

Soft and can be cut with a knife

Question 27

What happens when alkali metals react with air

Answer 27

Metal oxides form

Question 28

What does it mean if an element is diatomic

Answer 28

It forms molecules consisting of 2 atoms

Question 29

What are the trends of the alkali metals

Answer 29

As you move down the group: The melting and boiling points decrease and the metals become more reactive

Question 30

What are the chemical properties of alkali metals

Answer 30

They all easily lose their one valence electron so they have similar chemical properties They react with oxygen to form metal oxides They react with water to form metal hydroxides

Question 31

What is the state of fluorine (and colour) at room temperature, then the colour in a solution

Answer 31

Yellow gas, pale yellow in solution

Question 32

What is the state of chlorine (and colour) at room temperature, then the colour in a solution

Answer 32

Pale yellow-green gas Green-blue in solution

Question 33

What is the state of bromine (and colour) at room temperature, then the colour in a solution

Answer 33

Red-brown liquid that readily evaporates to form a brown gas Orange in a solution

Question 34

What is the state of iodine (and colour) at room temperature, then the colour in a solution

Answer 34

Grey-black solid that readily sublimes to a purple gas Dark brown solution

Question 35

How do halogen replacement reactions work

Answer 35

When a more reactive halogen replaces a less reactive halogen, reactivity decreases down the group

Question 36

How do we test for halides

Answer 36

We take an unknown halide solution dissolved in nitric acid and then we add silver nitrate or Pb(NO3)2 and check the colour of the precipitate formed

Question 37

What color precipitate is AgCl

Answer 37

White

Question 38

What color precipitate is AgBr

Answer 38

Cream

Question 39

What color precipitate is AgI

Answer 39

Yellow

Question 40

What are the general properties and uses of transition metals

Answer 40

Hard,strong with high MP and density. Form coloured compounds as elements and in compounds Have ions with variable oxidation numbers (iron (II) and iron (III)) Titanium=limb replacement Dyes, stained glass jewelry

Question 41

Why are transition elements often used as catalysts

Answer 41

Because of their ability to easily interchange between oxidation states

Question 42

What are the general properties of noble gases (4)

Answer 42

Very low MP+BP Full outer shells Chemically inactive, inert and unreactive due to their stable electronic configuration Monatomic colour less gases

Question 43

What are the uses of noble gases

Answer 43

Helium->balloons, less dense than air and doesn’t burn Neon,argon and xenon->advert signs Argon->inert atmosphere for welding Argon->fill electrical bulbs

Question 44

What is group 6 of the periodic table called

Answer 44

The chalcogens

Question 45

How do we test the reactivity of alkali metals

Answer 45

By reacting them with water

Question 46

How do we further confirm the presence of halide ions Cl Br I

Answer 46

We add aqueous ammonia Soluble(clear) Partially soluble Insoluble(visible precipitate)

Question 47

Periodic table

Answer 47

Arrangement of elements in periods and groups and in order of increasing proton number

Question 48

Reactions of halogens

Answer 48

Displacement reactions with halides, the more reactive halogen atoms oxidise the less reactive halide ions causing them to lose electrons and form halogen atoms.