particle model of matter

Question 1

what does the particle model help show

Answer 1

explains how the particles at each stage behave

Question 2

what are the forces of attraction in liquids

Answer 2

weak

Question 3

why are solids fixed

Answer 3

they have strong forces of attraction

Question 4

what happens when a gas is heated

Answer 4

pressure increases/container expands

Question 5

what happens at each stage from gas to liquid to solid

Answer 5

strength of bonds / density increase

Question 6

what is density measured in

Answer 6

g per cm3

Question 7

density practical

Answer 7

find mass of object using mass balance
if it is regular find volume by finding lwh
if it is irregular use eureka can filled with water up to outlet with an empty measuring cylinder aligned underneath the outlet

the volume of the object will flow into the measuring cylinder
insert values into the equation

Question 8

what can we do to reduce the uncertainty of density experiments

Answer 8

take multiple measurements and calculate a mean
When measuring the density of liquids, use a larger volume of liquid

Question 9

on a graph of melting and boiling point over time why is there no temp increase at the certain melting and boiling points

Answer 9

the energy is being applied to the objects potential stores(forces holding particles together)

Question 10

why is the temp constant when cooling

Answer 10

when changing state new bonds are being formed which releases energy which is what counteracts cooling keeping temp constant

Question 11

what is the latent heat

Answer 11

the amount of energy needed to change state of substance while temp stays constant

Question 12

what is the spec latent heat

Answer 12

energy required to change 1 kg of a substance from 1 state to another without changing temp

Question 13

for cooling what is the spec latent heat

Answer 13

energy released by change in state

Question 14

what are the 2 types of slh

Answer 14

vapourisation-energy change when substance changes from liquid to gas(evaporates or condenses)

fusion-energy change when substance changes between solid and liquid(melts or freezes)

Question 15

slh of fusion and vapourisation when cooling would be

Answer 15

the amount of energy released instead of required

Question 16

what is the equation of spec latent heat

Answer 16

e=ml
energy released /required(j)=mass(kg)x spec latent heat(j/kg)

Question 17

how is pressure formed in a container

Answer 17

by the force gas particles exert on the walls of a container whenever they collide with it

Question 18

what is the total pressure

Answer 18

no of collisions
energy of collisions

Question 19

what factors affect gas pressure

Answer 19

temperature(inc
concentration(inc
volume(inc as it decreases

Question 20

How volume affects pressure in a gas

Answer 20

Decreasing the volume of the container, whilst keeping the number of gas particles the same, will increase the concentration.
In this smaller volume, collisions between particles of gas and the walls of the container will be more frequent.
A greater number of collisions per unit area of wall means the pressure increases.

Question 21

How temperature and concentration affect a flexible container

Answer 21

Some containers, such as balloons, are flexible.
An increase in force on the walls of the container would just cause the container to expand.
Therefore, changing temperature or concentration will change the volume of the container, rather than the pressure of the gases inside.

Question 22

pressure x volume in 2 containers=

Answer 22

constant volume at constant temp

Question 23

pressure and volume are

Answer 23

inversely related