Combination and Decomposition Reaction

A decomposition reaction can be recognized because it has...

• only one product

• only one reactant

• 2 or more reactants and 2 or more products

• the presence of a catalyst

A chemical change in which two substances react to form a new substance is a ____________________________.

• decomposition reaction

• Combination reaction

• precipitation reaction

• combustion reaction

Before burning in air, the magnesium ribbon is cleaned by rubbing with a sand paper to:

• Make the ribbon surface shinier

• Remove the layer of magnesium oxide from the ribbon surface

• Remove the layer of magnesium carbonate from the ribbon surface

• Remove the moisture from the ribbon surface

When ferrous sulphate is heated strongly it undergoes decomposition to form ferric oxide as a main product accompanied by a change in colour from:

• Blue to green

• Green to blue

• Green to brown

• Green to yellow

A decomposition reaction occurring with help of heat energy is (a)  

Initial colour of ferrous sulphate crystals is (a)  

Ferrous Sulphate is a ______ salt with formula____________

(a)  

On being heated the colour of Ferros sulphate changes to (a)   initially.

On sustained heating the colour of Ferrous sulphate crystals changes to (a)  

The gases liberated when ferrous sulphate is heated strongly have a (a)   odour.