Reactivity Series

What is the reactivity series, in order of decreasing reactivity, ?

Potassium

Sodium

Lithium

Calcium

Magnesium

Aluminium

Carbon

Since

Iron

Hydrogen

Copper

Silver

Gold

metal + water --->

metal hydroxide + hydrogen

metal + steam --->

metal oxide + hydrogen

What happens when we react metals in the reactivity series with water ?

( which metals do what )

metals above hydrogen :

react with water or steam to produce, metal hydroxide + hydrogen or metal oxide + hydrogen

and effervescence is produced


Metals below hydrogen don't react with water/steam

What happens when we react metals in the reactivity series with dilute acid ?

potassium, sodium, lithium and calcium aren't reacted with dilute acids, because it is too reactive

( apart from very diluted calcium)

metals below this but above hydrogen , react and produce effervescence:
magnesium- vigorously

aluminium- vigorous but slow to react

zinc and iron- slow to react not very vigorous


metals below hydrogen don't react with dilute acid

metal + dilute sulfuric acid -->

metal sulfate + hydrogen

metal + dilute hydrochloric acid --->

metal chloride + hydrogen

metal + acid -->

salt + hydrogen

What conditions are required for iron to rust ?

iron rusts in the presence of oxygen and water

Fe2O3 . XH2O

What are the methods of preventing rusting ?

Barriers

Galvanising

Sacrificial Protection

How does the barrier method prevent rusting ?

it coats the iron in a paint, oil, grease or plastic or a metal below it in the reactivity series

How does galvanising prevent rusting ?

it coats iron in a layer of zinc, as zinc is more reactive than iron and reacts more with oxygen and water

and prevents water and oxygen reaching the iron

It is both barrier and sacrificial protection

How does sacrificial protection prevent rusting ?

Sacrificial protection is adding metal blocks which are more reactive than iron, to prevent the iron from reacting with oxygen and water in the atmosphere

What does oxidation mean ?

oxidation is the gain of electrons and the ( gain of oxygen )

What does reduction mean ?

reduction is the loss of oxygen and loss of electroncs

What does the term redox reaction mean ?

a reactions where oxidation and reduction take place simultaneously

What does the term reducing agent mean ?

a substances that reduces something else

(a reducing agent gets gets oxidised in a chemical reaction )

What does the term oxidising agent mean ?

a substance that oxidises something else

( a oxidising agent gets reduced in a chemical reaction )

What is a displacement reaction ?

A reaction in which a more reactive element takes the place of a less reactive element in a compound

How to write a half equation ?

1. Write down the reactant and the product.

2. Balance the atoms.

3. Write the total charge underneath each species in the equation.

4.Balance the charge by adding electrons.

Practical : Investigate reactions between dilute hydrochloric acid and sulfuric acid and metals