Chemical Analysis And Chemistry Of Atmosphere

Question 1

What is a pure substance in chemistry ?

Answer 1

Something that only contains one compound or element, not mixed with anything

Question 2

How to figure out how pure a substance is ?

Answer 2

The boiling or melting point of the compound or element

Question 3

What are formulations ?

Answer 3

Are mixtures with exact amounts of components

Question 4

What are chromatography’s two main phases ?

Answer 4

The mobile phase and a stationary phase

Question 5

What to calculate the Rf value ?

Answer 5

Rf=distance travelled by substance (distance from baseline to center of the spot) /distance travelled by solvent (distance moved by solvent)

Question 6

What is the Rf value ?

Answer 6

It is the ratio between the distance travelled by the dissolved substance (the solute) and the distance traveled by the solvent.

Question 7

What are the 4 tests from the comman gasses

Answer 7

1-chlorine
2-oxygen
3-carbon dioxide
4-hydrogen

Question 8

What is the result and test for chlorine ?

Answer 8

The chlorine bleaches the litmus paper and it will turn it white

Question 9

What is the result and test for oxygen ?

Answer 9

Glowing splint inside the tea tube containing oxygen, the oxygen will relight the glowing splint if present

Question 10

What is the result and test for carbon dioxide?

Answer 10

Carbon dioxide with limewater causes the solution to turn cloudy

Question 11

What is the result and test for hydrogen?

Answer 11

A lot splint is held near the test tube containing hydrogen gas and it will pop if hydrogen is present

Question 12

How can you test for various metal ions ?

Answer 12

By heating your substances and seeing whether it burns with a distinctive colour flame

Question 13

Lithium ions burn with what flame ?

Answer 13

Crimson flame

Question 14

Sodium ions burn with what colour flame ?

Answer 14

Yellow

Question 15

Potassium onions burn with what colour flame ?

Answer 15

Lilac flame

Question 16

Calcium ions burn with what colour flame?

Answer 16

Red/orange

Question 17

Copper ions burn with what colour flame

Answer 17

Green flame

Question 18

What do you do the flame tests on metal ions ?

Answer 18

-Dip platinum wire loop in some dilute HCl
-then hold it in a blue flame until it burns without any colour
-then dip the loop into the sample you want to test and put it back in the flame and record the colour

Question 19

When did the world start?

Answer 19

Around 4.6 billion years ago

Question 20

The early atomospher was mostly what gas and why ?

Answer 20

Carbon dioxide due to all the volcanos erupting

Question 21

Evolution of atmospher ?

Answer 21

-Volcanos give out CO2
-oceans,algae and green plants absorb CO2 from the atmosphere
-green plants and algae produce oxygen through photosynthesis

Question 22

What do greenhouse gasses do ?

Answer 22

Act as an insulating layer in the earths atmosphere makes the earth warm but when there is to much is deflects of the atmosphere and keeps bouncing back of earth creating global warming

Question 23

What could climate change cause?

Answer 23

-higher global temperatures
-changes in rainfall patterns
-frequency and serverity of storms increases
-changes in temp and amount of water available will affect wild species

Question 24

What are carbon footprints ?

Answer 24

A measure of the amount of carbon dioxide and other greenhouse gasses released over life cycle

Question 25

Ways to reduce carbon footprint are ?

Answer 25

-renewable energy -more suffiecent processes could conserve energy -government could tax company’s due to greenhouse gasses emitted -government could cap amount of greenhouse gasses committed

Question 26

How does fossil fuels cause pollution?

Answer 26

When hydrocarbons in fossil fuels are combusted the compounds are oxidised so carbon dioxide and water vapour and realised in the atmosphere