Reactivity

Página 1

What is reactivity?

The rate at which a chemical

substance tends to undergo a chemical reaction

Metals in water

experiment

To test the reactivity of

metals in water

Equipment

5 boiling tubes

Boiling tube rack

5 small metal samples, roughly equal in size

Method

Half fill five boiling tubes with water

Add a piece of one of the metals into one of the boiling tubes and observe

Repeat for the other four metals

Alkali Metals

A group of metals on the left

hand side of the periodic table in group 1. This includes:

Li

Na

K

Rb

Cs

Fr

Alkali metals properties

They have low densities so

float on water

Softer so they can be cut with

a knife

More reactive, they react

vigorously with water

ALKALI METAL + WATER --> ALKAI METAL HYDROXIDE + HYDROGEN

Metals and acid

Most metals except copper,

silver and gold react with acid to produce a metal salt and hydrogen

Zinc + nitric acid à zinc nitrate + hydrogen

Magnesium + hydrochloric acid à Magnesium chloride + hydrogen

We can test for hydrogen by using a lit splint which would give a

squeaky pop is hydrogen is present

Metals and oxygen

Most metals react with oxygen

to form metal oxides

METAL + OXYGEN --> METAL OXIDE

Displacement

reactions

Displacement reaction – when a

more reactive metal takes the place of a less reactive metal from it’s

compound, often we use metal salt solution e.g copper sulphate

Iron + Copper sulphate --> Copper + iron sulphate

We see this copper as coating on the iron nail