Experimental Techniques and Processes (whole Course Stuff)

Question 1

Safe method of heating up a flammable mixture

Answer 1

Hot water bath

Question 2

Why wrap a wet paper towel or place a cold water test tube over the top of reaction mixture

Answer 2

Acts as a condenser to prevent escape of reactants

Question 3

How to make up a standard solution

Answer 3

• Accurately weigh the mass of the solute and add to a beaker.
• Add water to the beaker until the solute dissolves.
• This solution is then added to a volumetric flask.
• The beaker in then rinsed with more water and the rinsing added to the volumetric flask
• water is then added to the volumetric flask up to the mark.

Question 4

Define a standard solution

Answer 4

Solution of accurately known concentration

Question 5

What is Distillation

Answer 5

Distillation is a technique used to separate two liquids in a solution

Question 6

Instrument to achieve rough volume measurements

Answer 6

Beaker

Question 7

Instrument to achieve an accurate volume measurement

Answer 7

Measuring cylinder

Question 8

Instrument to measure 25cm^3 of liquid (normally titrations)

Answer 8

Pipette

Question 9

Test for hydrogen

Answer 9

Burns with a POP

Question 10

Test for carbon dioxide

Answer 10

Turns limewater cloudy

Question 11

Purpose of chromatography

Answer 11

Chromatography is used to separate substances in complex mixtures

Question 12

Volumetric analysis

Answer 12

Volumetric analysis uses a solution of accurately known concentration (standard solution) in a reaction to determine the concentration of another

Question 13

Use of Titration reactions

Answer 13

Titrations are used to accurately determine the volumes of solution required to reach the end point of a chemical reaction

Question 14

Use of Redox Titration

Answer 14

Redox titrations are titrations based on redox reactions and used to determine the unknown concentration of a solution

Question 15

Concordant values

Answer 15

Values that are within 0.2cm^3 of each other

Question 16

Acidified Permanganate follows what colour change when reduced

Answer 16

Purple to Colourless

Question 17

Colour change of Copper 2 Oxide when reduced

Answer 17

Black to brown solid

Question 18

Colour change acidified dichromate solution when reduced

Answer 18

Orange to green

Question 19

Colour change of Felings Solution when reduced

Answer 19

Blue to Brick Red

Question 20

Colour change of Tollens reagent when reduced

Answer 20

Forms a silver mirror