When Fireworks Burn in Air, They Are Reacting with the Gas

HELP

1Copy and complete these sentences.

When fireworks burn in air, they are reacting with the gas

. When magnesium burns in oxygen, it forms a

white powder called magnesium . Black

copper oxide forms when copper metal is in air.

2A grey metal powder was sprinkled into a Bunsen burner flame. It glowed very brightly. A white powder formed.

Use the information above to help you answer these questions.

aWhat tells you that the metal probably burned in the Bunsen flame?

bWhy is the white powder probably a metal oxide?

CORE

3Here is a word equation for thecombustion reaction of magnesium:

Write a word equation for these reactions:

acopper reacting with oxygen to form copper oxide

bcarbon reacting with oxygen to form carbon dioxide

csodium burning in air.

4In an experiment, equal-sized pieces of phosphorus were placed into each of two gas jars A and B. The phosphorus burst into flames and burned in both jars. It burned brighter and for a longer time in jar A than in jar B.

aWhat can you deduce that was similar about the gas in both jars?

bExplain how you reached your answer to part a.

cIn what way do you think the gas in the jars might have been different?

dExplain why you think it was different.

5Copy and complete these word equations for combustion reactions.

a + oxygen iron oxide

bhydrogen + oxygen  (Hint: not hydrogen oxide.)

This worksheet may have been altered from the original on the CD-ROM.

EXTENSION

6Here is the reaction between sulphur and oxygen, shown as a ‘particle picture’.

/ + / /  /

aiExplain why the particles shown in the picture can bedescribed as ‘balanced’.

iiExplain how you can tell, from the particle picture only, thata chemical reaction has taken place.

iiiIf represents sulphur and represents oxygen, suggesta suitable name for the product.

bHere is the word equation for the formation of water fromhydrogen and oxygen:

hydrogen + oxygen water

Draw a particle picture version of the equation, starting withhydrogen. This is a hard question, so take your time to thinkabout it.

The particle picture for hydrogen is /
The particle picture for oxygen is /
The particle picture for water is /

This worksheet may have been altered from the original on the CD-ROM.