Metals

Metals are on the LHS of The Periodic table Properties of Metals

Metal Use Property

Mercury Thermometers Liquid at room T

Aluminium Aircraft body Strong/ low density

Gold Jewellery Unreactive

Lead Weights Very dense

Titanium Aircraft engine Very high MP

Copper Cables Good electrical conductor

Properties Malleable – can be beaten into shape Ductile – can be drawn out into a wire Strong, hard. Shiny – metallic lustre. Good conductors of heat and electricity. Density – varies ( data book) Metals usually have High MP and BP They are solids at room temperature – Mercury is

the only liquid metal at room T.

Metal reactions

Metal + Oxygen —> Metal oxide The energy change in the reaction depends

on how reactive the metals are. Alkali metals stored in oil. They react with

O2 in air.

Other metals react

more slowly.

Metal + Water

Metal + Water —> Metal hydroxide + Hydrogen

Example Sodium + Water —> Sodium hydroxide +

Hydrogen 2Na + 2 H2O —> 2 NaOH + H2

Metal + Acid

Metal + Acid —> Salt + Hydrogen Example Magnesium + Hydrochloric Acid —>

Magnesium chloride + Hydrogen

Mg +2 HCl —> MgCl2 + H2

Metal ReactionsMetal React with O2 React with H2O React

with H+

Potassium YES YES YES!!!!

Lithium YES YES YES!!!

Magnesium YES YES YES

Aluminium YES YES

Iron Yes - surface YES

Lead Yes - surface YES

Copper Yes - surface

Silver

Mercury

The Reactivity Series This is a list of metals in the order they react, The most reactive metal is at the top. K Na Li Ca Mg Al Zn Fe Sn Pb Cu Hg Ag Au

Metal Ores

A metal ore is a naturally occurring compound of a metal.

We have to extract the metal from its ore to use it.

Metals are a finite resource – they will run out.

They can be recycled. Some metals are found un combined in the

earth – not in a compound e.g. Gold, Silver.

Extracting Metals from their Ores Some metals can be removed by heat alone – un

reactive metals e.g. Copper, Silver. Others need to be heated with C or CO or H – they

remove the O in the compound leaving the metal element. ( Zn ---> Pb)

Example Iron oxide + Carbon monoxide ----> Iron +

Carbon dioxide The more reactive metals have to removed by

electrolysis e.g. Al ---->K

The Blast Furnace Iron is separated from Iron Oxide in a structure called the Blast Furnace. 3 raw ingredients are added at the top. Coke, Iron Ore and limestone. A blast of hot air enters at the bottom, this provides heat for the reactions: Carbon monoxide + Iron Ore -----> Iron + carbon dioxide. Carbon dioxide + Coke -----> Carbon monoxide Coke + Oxygen ------> Carbon dioxide The molten iron runs out at the bottom. The limestone decomposes to impurities – SLAG. Slag can be used for insulation in building

industry.

Alloys

Alloys are metals melted together.

They are made to enhance the properties of the metals.

Alloy Elements in it Properties

Brass Zn, Cu Low MP, shapes easy

Solder Sn,Pb Low MP

Steel Fe, Cr, Ni Strong, no corrosion

Cupro Nickel Cu, Ni Cheap, hard

Calculations using Equations What mass of Cu will be produced when 6.5g of Zn are added to

CuSO4 ? 1. Balanced Equation Zn + Cu SO4 ------> ZnSO4 + Cu 2.Mole Ratio: Zn:Cu = 1:1 3. Actual number of moles – Mass given/mass of 1 mole Zn = 6.5/65 = 0.1 4. New ratio If 1 mole Zn gives you 1 mole of Cu then 0.1 moles will give you

0.1 moles of Cu. 5. Mass produced I mole Cu = 64g x 0.1 = 6.4g

Empirical Formula – basic formula Calculate the Empirical formula of a metal ore if it contains6.4g

of Cu and 1.6g of O 1. List elements Cu O 2. Mass present 6.4 1.6 3. Mass of 1 mole 64 16 4. Number of moles 6.4/64 1.6/16 ( mass given/mass 0.1 0.1

of 1 mole) 5. Convert to whole 0.1/0.1 0.1/0.1

number – 1 1divide both by smallest no. 6. Ratio 1 : 1Empirical Formula Cu O