Laboratory techniques

Question 1

Personal safety

Answer 1

Consistent use of safety goggles, laboratory coat, close toed shoes, gloves, fume hood, facemask or rest or respirator

Question 2

Accuracy

Answer 2

A measurement giving the actual value for the sample with a limited deviation

Question 3

Precision

Answer 3

The repeatability of a set of measurements on the same sample

Question 4

Glassware

Answer 4

Used because of its strength, inertness, transparency and heat resistance

Question 5

Non-calibrated glassware

Answer 5

Test tubes, speakers, Erlenmeyer flask, round bottom flask, transfer/pasture pipettes, petri dishes, watch glasses, bottles, jars and vials. Volume markings are approximate and they should not be used for actual measurements

Question 6

Calibrated glassware

Answer 6

Graduated cylinder, buret, graduated pipette, volumetric pipette, volumetric flask. Used for any laboratory measurement that requires accuracy and precision. Manufactured to provide exact volume at a given temperature, 25°C

Question 7

pH meter

Answer 7

Determines the acidity or basic city of a solution by comparing the voltage (electrical potential) produced by the solution compared to the voltage of a known standard solution and uses the difference in voltage (the potential difference) between them to calculate the pH

Question 8

Standard laboratory balances/top loading balances

Answer 8

Used when weights are in the milligram range and require accuracy to within plus or minus 0.5 mg

Question 9

Analytical balances

Answer 9

Used for sensitive weighing applications with accuracy to plus or minus 0.01 mg