2025-2026 Revision for test 1

(a) i Particles together.

(ii) Particles in a solid are in positions

Particles in a solid

Particles in a liquid can (past each other) as forces between particles in a liquid are than in a solid 

Particles are quickly (in all directions) 

Particles are far 

Particles spread out

forces between the particles 

to remove the sand  (as) sand is in water / sodium chloride is

the filtered mixture  (Solid) sodium chloride stays in flask and pure water evaporates then

She is not correct

sample 4 has range higher than 110^oC and B cannot have melting point 110^oC

Pure samples do not melt over a (of temperatures)

Pure samples have a melting point

Impurities the melting point

Sample 1 is likely to be pure as it has the narrowest range of melting point

(i)

(ii) M1 the condenser the ethanol vapour

M2 so it condenses

OR forms (ethanol)

They will not diffuse into the (at the bottom of beaker)

so that the dyes can up the paper

(ii) Explain which two felt tip pens contain the same dye.

E and

as the both have a spot at the same

Or both have a dot with the same

(iii) The student thought that both F and G contained only one dye. Explain why the student can only be certain about one of these dyes. (2)

M1 The student can only be certain about G containing one dye as only spot

As F is so you cannot tell how many dyes it has