Chem Chapter 1 - Experimental Chemistry

Question 1

what is the si unit and symbol for time

Answer 1

second s

Question 2

what is the si unit and symbol for temperature

Answer 2

kelvin K

Question 3

what is the si unit and symbol for length

Answer 3

metre m

Question 4

what is the si unit and symbol for mass

Answer 4

kilogram kg

Question 5

what is the si unit and symbol for volume

Answer 5

cubic metre m3

Question 6

what apparatus is used to measure time

Answer 6

digital stopwatch analogue stopwatch

Question 7

what apparatus is used to measure temperature

Answer 7

thermometer

Question 8

what apparatus is used to measure length

Answer 8

metre ruler measuring tape

Question 9

what apparatus is used to measure mass

Answer 9

beam balance electronic balance

Question 10

what apparatus is used to measure volume

Answer 10

pipette volumetric flask burette gas syringe

Question 11

how accurate is the digital and analogue stopwatch

Answer 11

nearest 0.01s and 0.1s

Question 12

how accurate is the electronic balance

Answer 12

nearest 0.1g

Question 13

what are beakers and conical flasks for

Answer 13

collecting liquid

Question 14

what does a pipette measure

Answer 14

accurate fixed volumes less than 100cm3

Question 15

how accurate is a measuring cylinder and burette

Answer 15

0.5 and 0.05cm3

Question 16

what solubility of gas in water does water displacement method depend on

Answer 16

insoluble to slightly insoluble

Question 17

what solubility of gas in water does downward delivery method depend on

Answer 17

can be soluble or insoluble

Question 18

what are the three gas collection methods

Answer 18

water displacement method
downward delivery
upward delivery

Question 19

what solubility of gas in water does downward delivery method depend on

Answer 19

can be soluble or insoluble

Question 20

how does the density of gas collected in water displacement method affect the collection

Answer 20

density doesnt effect

Question 21

how does the density of gas collected in downward delivery method affect the collection

Answer 21

denser than air

Question 22

how does the density of gas collected in upward delivery method affect the collection

Answer 22

less dense than air

Question 23

name three examples of gases commonly collected in water displacement method

Answer 23

hydrogren oxygen carbon dioxide

Question 24

name three examples of gases commonly collected in downward delivery

Answer 24

chlorine, hydrogren chloride, sulfer dioxide

Question 25

name three examples of gases commonly collected in upward delivery

Answer 25

ammonia

Question 26

name three methods of separating solid-solid mixtures

Answer 26

magnetic attraction sieving using suitable solvents

Question 27

what is the use of sieving

Answer 27

separates bigger particles from smaller particles

Question 28

name 2 methods of separating liquid-liquid mixtures

Answer 28

chromatography fractional distillation

Question 29

explain the 5 steps of fractional distillation

Answer 29

when heating the solution, both higher boiling point liquid vapour and lower boiling point liquid vapour will rise since the higher boiling point liquid has a higher boiling point than the lower boiling point liquid, the vapour condenses onto the cool fractioning collumn. then the higher boiling point liquid returns to the flask lower boiling point liquid vapour continues to rise until boiling point then exits through the sidearms hot lower bp liquid cools and condenses into liquid liquid lower bp liquid flows into receiver

Question 30

name the four separation methods of solid-liquid mixtures

Answer 30

filtration evaporation to dryness crystallisation simple distillation

Question 31

what is the use of evaporation to dryness

Answer 31

separates dissolved solids from its solvent by heating the mixture until solvent has vaporised

Question 32

what is the use of crystallisation

Answer 32

obtains pure solid from saturated solutions

Question 33

explain the steps of crystallisation

Answer 33

heat solution in evaporating dish until solution is saturated cool solution until desired residue appears within the solution filter the mixture and collect residue

Question 34

explain the three steps to simple distillation

Answer 34

heat solution then add boiling chips. at the liquids boiling point it will boil and enter the condenser the liquid vapour cools in condenser and condenses into pure liquid form and collected in the flask as distillate the remaining solution gets more concentration and leaves residue in distillation flask

Question 35

what is the relationship between amt of impurities in a substance and the change in melting or boiling points + range

Answer 35

the higher the amt of impurities the larger the change in boiling or melting points and the wider the range

Question 36

what are the three gas drying agents

Answer 36

concentrated sulfuric acid calcium oxide quicklime fused calcium chloride

Question 37

what is the use of concentrated sulfuric acid

Answer 37

non alkaline drying

Question 38

what is the use of calcium oxide quicklime

Answer 38

non acidic drying

Question 39

what is the use of fused calcium chloride

Answer 39

drying most gases