C1 - particles (from PMT)

Question 1

describe the arrangement and movement of particles in solids

Answer 1

-particles are packed closely together in a regular arrangement
-the particles vibrate in fixed positions

Question 2

describe the arrangement and movement of particles in liquids

Answer 2

-the particles are close together but able to move past each other
-the particles vibrate and move around each other

Question 3

describe the arrangement and movement of particles in gases

Answer 3

-the particles are well separated with no regular arrangement
-the particles vibrate and move freely at high speeds

Question 4

how does a physical change differ from a chemical change?

Answer 4

-a physical change involves changes in the forces between particles. the particles themselves remain the same and the chemical properties remain the same
-a chemical change is different as it affects the chemical properties of the substance

Question 5

describe what happens in terms of particles when a solid is heated and melts into a liquid

Answer 5

-when heated, particles absorb thermal energy and convert it into kinetic energy
-the particles in the solid vibrate more, causing the solid to expand until the structure breaks and the solid turns into a liquid

Question 6

describe what happens in terms of particles when a solid is heated and melts into a gas

Answer 6

when heated, the particles in a liquid expand. some particles on the surface gain sufficient energy to overcome the intermolecular forces and evaporate. at the boiling point, all of the liquid particles gain enough energy to evaporate.

Question 7

why do solids liquids and gases expand when heated?

Answer 7

when a substance is heated the molecules vibrate faster. this causes the space between the atoms to increase

Question 8

what are particles in the particle model represented by?

Answer 8

inelastic spheres

Question 9

what does the particle model not take into account?

Answer 9

-the forces of attraction between particles
-the size of particles and space between them

Question 10

how did jj thomson discover the electron?

Answer 10

thomson conducted an experiment using a cathode ray tube. the beam moved towards the positively charged plate so he knew the particles must have a negative charge.

Question 11

describe jj thomson’s atomic model

Answer 11

plum pudding model - negative electrons scattered through a positively charged material