P3

• How to find the density of a solid object:

  1. use a balance to measure its mass
  2. if its a regular solid, start by measuring its length, width and hight with an appropriate peice of equipment, then calculate its volume using a formula
  3. For an irregular solid, Submerge it in a eureka can filled with water. the water displaced by the object will be transferred to the measuring Cylinder
  4. record the volume of water in the measuring cylinder, this is the objects volume. you then use the formula:

  Density= mass ÷ volume
• To find the density of a liquid

  1. place a measuring Cylinder on a balance
  2. pour 10 ml Of the liquid into the Cylinder and record the mass. Continue this untill the cylinder is full.
  3. for each measurement, use the formula to find the density
  4. finally take an average of the densities, this will be your value
• Internal energy is the total energy stored by particles in a system

  • The particles in a system vibrate or more around so they have energy in their kinetic energy stores
  • They also have energy in their potential energy stores due to their positions
  • the energy stored in a system is stored by its atoms and molecules. The internal energy of a system is the total energy that its particles have in their Kinetic and potential energy stores
  • Heating the system transfers energy to the particles increasing the internal energy
• A change of state is a physical change, not a chemical change because you don't get a new substance

  It is reversable

  Number of particles doesn't change