Combustion

Question 1

a gas that can be used as a fuel:

Answer 1

Hydrogen

Question 2

what do most hydrogen powered vehicles use?

Answer 2

fuel cells

Question 3

hydrogen +____—— water

Answer 3

oxygen

Question 4

does hydrogen combust with oxygen?

Answer 4

yes but it needs energy from a spark or flame to start the reaction

Question 5

a combustion reaction continues until one or both reactants :

Answer 5

have been used up

Question 6

give examples of fossil fuels

Answer 6

petrol and diesel

Question 7

what are fossil fuels made of ?

Answer 7

oil from living organisms that have died millions of years ago

Question 8

examples of hydrocarbons :

Answer 8

petrol and diesel

Question 9

hydrocarbon as a word equation

Answer 9

hydrocarbon + oxygen ——- water +carbon dioxide

Question 10

is combustion an oxidation reaction?

Answer 10

yes

Question 11

what do hazard symbols explain ?

Answer 11

why a substance must be handled carefully

Question 12

complete combustion

Answer 12

the fuel reacts completely with oxygen

Question 13

incomplete combustion

Answer 13

the fuel only partly reacts with oxygen

Question 14

many products from burning fossil fuels are

Answer 14

pollutants they harm habitats and their organisms

Question 15

acid rain

Answer 15

rain water which has been made more acidic by dissolved sulfur dioxide and nitrogen oxides

Question 16

how are some of these acid rain making gases removed ?

Answer 16

neutralization and by using catalytic converters . catalytic converters also remove carbon monoxide

Question 17

what do green house gasses in the earth’s atmosphere do?

Answer 17

they keep the earth’s surface warm this is the greenhouse affect

Question 18

greenhouse gas example:

Answer 18

carbon dioxide

Question 19

what is the best way to reduce global warming

Answer 19

to reduce the amount of carbon dioxide released into the air

Question 20

what does it mean if a reaction is exothermic

Answer 20

it releases energy from the system in the form of heat

Question 21

endothermic

Answer 21

the system absorbs energy from its surrounding in the form of heat

Question 22

why should water never be used on an electric fire

Answer 22

because it conducts electricity

Question 23

a boiling tube of hydrogen burns with a ..

Answer 23

squeaky pop

Question 24

water turns coblat chloride _____ and anhydrous copper _____

Answer 24

water turns coblat chloride PINK and anhydrous copper BLUE

Question 25

when a hydrocarbon fuel combust it apears to ____ air because _____

Answer 25

when a hydrocarbon fuel combust it appears to lose air because products of the reaction ( carbon dioxide , water vapour ) are lost in air