Combustion: using oxygen - SC20

Question 1

what does complete combustion of hydrocarbons produce? how is energy given?

Answer 1

carbon dioxide + water

energy given out

Question 2

what does incomplete combustion of hydrocarbons produce? how is energy given?

Answer 2

carbon dioxide + carbon monoxide + water
energy given out but less than complete combustion

Question 3

what is supplied plentifully in complete combustion?

Answer 3

oxygen gas

Question 4

what is in limited supply in incomplete combustion?

Answer 4

oxygen gas

Question 5

what are the problems of incomplete combustion?

Answer 5

• Carbon monoxide (product) is a toxic gas that combines with haemaglobin in red blood cells preventing oxygen combining
• CO is a colourless and odourless gas
• People feel sick or become unconcious when in contact

Question 6

What is the test for water in complete combustion?

Answer 6

using white anhydrous copper sulfate in a u-shaped tube, turns blue colour

Question 7

what is the test for carbon dioxide in complete combustion?

Answer 7

use limewater in a boiling tube, turns cloudy

Question 8

what is the balanced equation for the complete combustion of C8H18 (octane)?

Answer 8

2C8H18 + 25O2 -> 16C02 + 18H2O

Question 9

What is the general word equation for complete combustion of any hydrocarbon?

Answer 9

hydrocarbon + oxygen -> carbon dioxide + water