[chem] experimental techniques

Question 1

instrument for measuring time?

Answer 1

digital stopwatch

Question 2

instrument for measuring temperature

Answer 2

laboratory thermometer

Question 3

instrument for measuring mass

Answer 3

electronic balance

Question 4

instrument for measuring approximate solution of liquid or solution

Answer 4

marked/graduated beaker

Question 5

instrument for measuring accurate volume

Answer 5

measuring cyclinder

Question 6

instrument for measuring very accurate volume

Answer 6

pipette and burette and volumetric flask

Question 7

instrument for measuring volume of gas

Answer 7

marked/graduated gas syringe

Question 8

accuracy of stopwatch

Answer 8

0.01s, but record to 1s in chem

Question 9

smallest division and accuracy of thermometer

Answer 9

1degC, measure to 0.5degC

Question 10

smallest division and accuracy of electronic balance

Answer 10

nil, 0.01g

Question 11

smallest division and accuracy of marked/graduated beaker

Answer 11

nil

Question 12

smallest division and accuracy of measuring cylinder

Answer 12

1cm3, measure to 0.5cm3

Question 13

smallest division and accuracy of pipette

Answer 13

nil

Question 14

smallest division and accuracy of burette

Answer 14

0.1cm3, measure to 0.05cm3

Question 15

smallest division and accuracy of volumetric flask

Answer 15

nil

Question 16

smallest division and accuracy of marked/graduated gas syringe

Answer 16

nil

Question 17

range of school alcohol thermometers

Answer 17

-10degC to 110degC

Question 18

what is marked/graduated beaker for

Answer 18

• use primary to hold or store liquids instead of measuring volume of liquids
• but can only hold approximate volume of liquids like approximately 100cm3

Question 19

what is pipette for

Answer 19

• measures very accurate fixed volume, e.g. 20cm3 and 25cm3
• cannot measure odd volumes like 21cm3 or 25.5cm3

Question 20

what is burette for

Answer 20

measures very accurate variable volumes between 0,00cm3 to 50.00cm3

Question 21

what is volumetric flask for

Answer 21

• measures accurate fixed volumes that are larger like 100cm3 or 250cm3
• commonly used for preparing a solution with known concentration

Question 22

what is measuring cylinder for

Answer 22

measures accurate variable volumes

Question 23

remarks for marked/graduated gas syringe

Answer 23

typical gas syringes in the laboratory measures volumes up to 100cm3

Question 24

common gases to collect and dry

Answer 24

• ammonia
• carbon dioxide
• chlorine
• hydrogen
• hydrogen chloride
• oxygen
• sulfur dioxide

Question 25

solubility of ammonia in water and density compared to air

Answer 25

extremely soluble less dense

Question 26

solubility of carbon dioxide in water and density compared to air

Answer 26

slightly soluble denser

Question 27

solubility of chlorine in water and density compared to air

Answer 27

soluble denser

Question 28

solubility of hydrogen in water and density compared to air

Answer 28

not soluble less dense

Question 29

solubility of hydrogen chloride in water and density compared to air

Answer 29

very soluble denser

Question 30

solubility of oxygen in water and density compared to air

Answer 30

very slightly soluble slightly denser

Question 31

solubility of sulfur dioxide in water and density compared to air

Answer 31

very soluble denser

Question 32

what is Mr of dry air

Answer 32

29.0

Question 33

what is relative molecular mass

Answer 33

sum of all the relative atomic mass (Ar) for all the atoms in a given formula

Question 34

methods to collect gas and suitability

Answer 34

- displacement of water (for insoluble or slightly soluble in water) - displacement of air (for very soluble in water) - downward displacement in air/upward delivery of gas (for less dense than air) - upward displacement of air/downward delivery of gas (denser than air) - using a graduated gas syringe