2.2.3a Melting, boiling, condensation and solidification

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49

Question 25

Define specific latent heat of fusion.

[1]

A test-tube contains $g50\text{ g}$ of liquid naphthalene at its melting temperature of $80∘C80^\circ\text{C}$ . An identical test-tube contains $g50\text{ g}$ of a mixture of solid and liquid naphthalene at a temperature of $80∘C80^\circ\text{C}$ .

Both test-tubes are placed in a water bath maintained at a constant temperature of $95∘C95^\circ\text{C}$ .

State and explain which test-tube contains naphthalene with the lower temperature after 5 minutes.

statement $…\dots$

explanation $…\dots$

[3]

When hand sanitizer containing alcohol is applied to a person's skin, it evaporates rapidly.

Explain, in terms of molecules, how the evaporation of alcohol cools the skin.

[4]

Explain why this cooling process is more effective if the person waves their hand.

[2]

Define specific latent heat of fusion.

[1]

Both test-tubes are placed in a water bath maintained at a constant temperature of $95∘C95^\circ\text{C}$ .

State and explain which test-tube contains naphthalene with the lower temperature after 5 minutes.

statement $…\dots$

explanation $…\dots$

When hand sanitizer containing alcohol is applied to a person's skin, it evaporates rapidly.

Explain, in terms of molecules, how the evaporation of alcohol cools the skin.

[4]

Explain why this cooling process is more effective if the person waves their hand.

[2]

2.2.3a Melting, boiling, condensation and solidification

Question 25

Markscheme

2.2.3a Melting, boiling, condensation and solidification

Question 25

Markscheme

2.2.3a Melting, boiling, condensation and solidification

Question 25

2.2.3a Melting, boiling, condensation and solidification Questions

2.2.3a Melting, boiling, condensation and solidification

Question 25

2.2.3a Melting, boiling, condensation and solidification Questions