CGP EDEXCEL IGCSE
CHEMISTRY REVISION
QUESTIONS AND
CORRECT ANSWERS
GRADED A+ 2025-2026
A substance keeps the same volume, but changes its shape according to the container
it's in. Is it a solid, a liquid or a gas? - ANS-Liquid
Are the forces of attraction between the particles in a liquid stronger or weaker than
those in a gas? - ANS-Stronger
Describe what happens when a substance changes from a liquid to a gas. - ANS-When a
liquid is heated, again the particles get even more energy. This makes the particles
move faster, which weakens and breaks the bonds holding the liquid together. At a
certain temperature, the particles have enough energy to break their bonds. This is
called evaporating and the liquid turns into a gas.
What is diffusion? - ANS-The gradual movement of particles from places where there
are lots of them to places where there are fewer of them. (Its just the natural tende ncy
for stuff to spread out.)
Describe an experiment that you can do to demonstrate diffusion. - ANS-Potassium
manganate (VII) and Water:
1. Take a beaker full of water and place some potassium manganate (VII) at the
bottom, the purple colour slowly spre ads out to fill the beaker.
CHEMISTRY REVISION
QUESTIONS AND
CORRECT ANSWERS
GRADED A+ 2025-2026
A substance keeps the same volume, but changes its shape according to the container
it's in. Is it a solid, a liquid or a gas? - ANS-Liquid
Are the forces of attraction between the particles in a liquid stronger or weaker than
those in a gas? - ANS-Stronger
Describe what happens when a substance changes from a liquid to a gas. - ANS-When a
liquid is heated, again the particles get even more energy. This makes the particles
move faster, which weakens and breaks the bonds holding the liquid together. At a
certain temperature, the particles have enough energy to break their bonds. This is
called evaporating and the liquid turns into a gas.
What is diffusion? - ANS-The gradual movement of particles from places where there
are lots of them to places where there are fewer of them. (Its just the natural tende ncy
for stuff to spread out.)
Describe an experiment that you can do to demonstrate diffusion. - ANS-Potassium
manganate (VII) and Water:
1. Take a beaker full of water and place some potassium manganate (VII) at the
bottom, the purple colour slowly spre ads out to fill the beaker.
