Experimental Techniques

Question 1

Measurement

Answer 1

Time : Digital stop watch
Measures up to 0.01s

Temperature: Mercury-in-glass thermometer
Measures up to nearest °C

Mass : Electric top-pan balance
Measures up to 0.01g

Volume : Beaker
Used to estimate liquid volume

Measuring cylinder: Measures up to 0.1 cm^3 (More accurate than beaker)

Pipette : Measures fixed volumes of liquids accurately (i.e. 20cm3)
Measures up to 0.1cm3

Burette : Used for measuring variable volumes of liquids accurately
Measures up to 0.1cm3

Question 2

Purity of a substance

Answer 2

The purity of a substance is defined as the degree to which a substance is undiluted or unmixed with other material. A pure substance therefore would be made of a single substance.

Question 3

Melting point

Answer 3

The melting point of a substance is the temperature in which the substance melts.

Question 4

Boiling points

Answer 4

the boiling point of a substance is the temperature at which it boils.