Periodic Table

Question 1

What are the characteristics of Mendeleev’s table?

Answer 1

Elements arranged in order atomic weight.
No noble gas present - not discovered.
Gaps left undiscovered elements (fewer elements).
No block of transitional metals.
Actinides and lanthanides not present.

Question 2

What are the characteristics of the modern periodic table?

Answer 2

Elements arranged order atomic number.
Noble gases present.
No gaps (more elements).
Block of transitional metals present.
Actinides and lanthanides present (at bottom).

Question 3

What are the properties of metals?

Answer 3

High melting point.
Malleable - easily hammered into shape.
Ductile - easily drawn into wire.
Sonorous - make ringing sound when struck.
Good conductors of heat and electricity.

Question 4

Properties of non-metals.

Answer 4

Low melting point (except graphite and diamond).
Not malleable - brittle.
Not ductile.
Not sonorous.
Poor conductors of heat and electricity (except graphite and diamond).

Question 5

Properties of group 1 metals?

Answer 5

Stored under oil, stop reacting with oxygen.
Soft and cut with knife.
Shiny but tarnish rapidly in air.
Low density (float on surface of water).

Question 6

Equations of alkali metals.

Answer 6

Alkali metal + Oxygen > Alkali metal oxide
Alkali metal + Water > Alkali metal hydroxide + Hydrogen

Question 7

What are the risk assessments of alkali metals and water?

Answer 7

1. Use tweezers when lifting. Prevents handling directly - could react with water in skin, causing burn.
2. Use safety screen. Prevents corrosive hydroxide solution splashing out, or metal sparking out and causing damage to skin.
3. Wear safety glasses. Prevents corrosive hydroxide solution splashing into eye and causing damage.
4. Use small piece p to avoid excessive splashing out, use large volume water in trough.

Question 8

What are the preparations of alkali metals for reactions?

Answer 8

1. Cut small piece.
2. Remove oil layer using filter paper.
3. Use tweezers to drop into large trough water, behind safety screen and wearing safety glasses.

Question 9

What are the observations of lithium?

Answer 9

Moves on water surface.
Heat released.
Disappears at end.
Colourless solution produced.

Question 10

What are the observations of lithium?

Answer 10

Moves on water surface.
Heat released.
Disappears at end.
Colourless solution produced.

Question 11

What are the observations of sodium?

Answer 11

Melts into tiny ball.
Moves on water surface.
Bubbles.
Heat released.
Disappears at end.
Colourless solution produced.

Question 12

What are the observations of potassium?

Answer 12

Lilac flame.
Melts into tiny ball.
Moves on water surface.
Bubbles.
Heat released.
Disappears quickly.
Colourless solution produced.
Crackles at end.

Question 13

What is the order of reactivity for lithium, potassium and sodium?

Answer 13

Lithium, sodium, potassium

Increases to right.

Question 14

What are the half equations of group 1 ions?

Answer 14

X > X+ + e-
Na > Na+ + e-

Question 15

Why does reactivity decrease down group 1?

Answer 15

Electron further from nuclear charge.
Less strongly attracted to positive nucleus and easier to lose.

Question 16

What are the colours of the group 7 halogens?

Answer 16

Fluorine - pale yellow gas.
Chlorine - Green-yellow gas.
Bromine - red-brown liquid.
Iodine - grey-black solid.

Question 17

What are the characteristics of the halogens?

Answer 17

Non-metals.
Do not conduct electricity.
Brittle and crumbly when solid.
Poisonous and smelly.

Iodine sublimes and produces purple vapour when heated.

Question 18

What are the half equations for group 7 ions?

Answer 18

X2 + 2e- > 2X-
I2 + 2e- > 2I-

Question 19

Why does reactivity decrease going down group 7?

Answer 19

When react gain one electron.
Outermost shell gets further from nucleus, force of attraction decreases.
More difficult to attract electron, and reactivity decreases.

Question 20

What are the colours of halogens in solutions from displacement?

Answer 20

Chlorine - place green.
Bromine - orange.
Iodine - brown.

Question 21

Tests for displacement of halogens?

Answer 21

Chlorine displaces bromine.
Colourless solution to orange.

Chlorine displaces iodine.
Colourless solution to brown.

Bromine displaces iodine.
Colourless solution to brown.

Chlorine (most), bromine, iodine

Question 22

What are the characteristics of noble gases?

Answer 22

All colourless gases at room temp.
Unreactive/inert - have full outer shells, don’t need to gain or lose electrons.
Boiling points increase down group.

Question 23

What are the colours of different copper substances?

Answer 23

Copper(II) oxide - black.
Copper(II) carbonate - green.
Hydrated copper(II) sulfate - green.
Copper(II) salts are usually blue in solution.

Question 24

What are the characteristics of group 1 metals compared to transitional metals?

Answer 24

Melting point - low
Density - low (less than water).
Reactivity with water - very reactive.
Formation of ions - form 1+ ions.
Colour of compounds - form white compounds.

Question 25

What are the characteristics of transitional metals compare to group 1 metals?

Answer 25

Melting point - high (except mercury).
Density - high.
Reactivity with water - low reactivity, react with steam.
Formation of ions - form ions with different charges.
Colour of compounds - form coloured compounds.