| How are the particles in a solid arranged? | The particles in a solid are packed together in a fixed arrangement with minimal spaced between then and strong intermolecular forces masking them not easily compressible. And the particles in a solid vibrate on the spot at a low energy allowing then to maintain their shape and from easily |
| How are the particles in a liquid arranged? | The particles in a liquid are close together with minimal spaces and weak intermolecular forces making them not easily compressible. The particles in a liquid have more energy than a solid allowing liquids to flow and take the shape of their container. |
| How are the particles in a gas arranged? | The particles in a gas are widely spaced with no intermolecular forces or regular arrangement which makes them easily compressible. And particles in a gas move quickly and randomly with high amount of energy allowing gasses to spread out and fill the space of their container |
| What is the equation for density? | D = m / v
Density (km/m^3) = m (kg) / volume (m^3) |
| How high is the density of a solid, liquid and a gas? | Solids and liquids have a very high density, but gases have a low density. |
| How much mass do solids, liquids, and gases have for their volume? | Solids and liquids have a lot of mass for their volume because their particles are packed closely together
Whereas gases have a small mass for their volume because their particles are very far apart |
| What solid has a low density? | Polystyrene is a solid with a low density because it has a very open structure and is full of air spaces, therefore it also has a small mass for its volume |
| How easy are the dimensions of regular and irregular objects to measure? | Regular objects have dimensions that are easy to measure, for example a cube can be measured with a ruler, but irregular objects have dimensions that are not easy to measure such as a vase |
| How is the volume of an irregular object measured? | The volume of an irregular object is measured using displacement.
This is done by filling a Eureka can with water and the Eureka can has a spout so water can flow out of the can.
The irregular object is now placed in the water and the water will become displaced and flow out through the spout (Into a measuring column)
The volume of water displaced is measured using a ruler and the volume of the water is the same as the volume of the object |
| What is potential energy? | Particles have potential energy which are the intermolecular forces and chemical bonds |
| What is sublimation? | Sublimation is when a solid directly changes to a gas, such as in the case of carbon dioxide at room temperature |
| What happens to mass when changed of state take place? | When changes of state take place, mass is always conserved, which means that particles are not added or subtracted |
| Are changes of state physical or chemical changes, and what does this mean? | Changes of state are physical changes which means that if the changes are reversed the material recovers it original properties |
| What is evaporation? | Evaporation is when only the surface particles of a liquid turn into a gas |
| What eqaution is specific heat capacity used in? | Specific heat capacity is used in the change in thermal energy eqauation |
| what does the line on a heating graph look like? | The line on heating graph looks like a diagonal line, then a horizontal line, then a diagonal, a horizontal line and a final diagonal line all, with the whole line pointing right |
| What happens on a heating graph? | In a heating graph a solid’s particles are melted into a liquid, the liquids particles are then further heated to boil into a gas and the gasses particles are further heated, shown at the end of the graph |
| Where are the melting and boiling points on a heating graph located? | On a heating graph the melting and boiling points are located on the first and second horizontal line |
| What happens in a cooling graph? | In a cooling graph a gas is condensed to a liquid and this liquid is frozen to a solid |
| When is the temperature constant on a heating graph? | The temperature is constant on a heating graph when a substance changes state |
| Why does the temperature of a substance become constant when it melts? | When a substance melts the temperature becomes constant because the energy put in is breaking the forces of attraction between the particles |
| What is latent heat?
And what is the specific latent heat of fusion? | Latent heat is the energy required for a substance to change state
And the specific latent heat of fusion is the energy require to change 1kg of a substance from a solid to a liquid without changing the temperature |
| What is the equation of the energy for a change of state? | E = m x L
Energy for a change of state (J) = Mass (kg) x Specific latent heat (J/Kg) |
| What is the pressure created by? | The pressure of a gas is created by particles colliding at right angles with the walls of the container the gas is held in |
| How can the pressure of a gas be increased? | The pressure of a gas can be increased by increasing the number of collisions per second or by increasing the energy of each collision, one way to do this is by increasing the temperature of the gas |
| What is the temperature of a gas directly proportional to? | The temperature of a gas is directly proportional to the average kinetic energy of the particles |
| Why do gasses have a low pressure at low temperatures and why do they have a high pressure at high temperatures? | At low temperatures, gases have a low pressure because the particles have a lower kinetic energy so there are fewer collisions per second
Therefore, at high temperatures, gases have a high pressure because the particles have higher kinetic energy so there are more collisions per second |
| What happens when the volume of the container is increased but the temperature is constant? | When the volume of the container is increased but the temperature is constant the spacing between the particles is increased, so they travel much further before colliding with the walls of the container, reducing the number of collisions per second, and therefore reducing pressure |
| What is the pressure of a gas inversely proportional to? | The pressure of a gas is inversely proportional to the volume, if the volume increases the pressure decreases |
| The is the equation for the pressure of a gas, and what does it mean? | Pressure of a gas = pressure (Pa) x Volume (m^3) = constant
which means if the pressure is doubled, the volume is halved because
pressure x volume = constant |
| When is work carried out on a gas? | Work is carried out on a gas when an applied forced causes an energy transfer |
