PPM 1 Flashcards
what is the definition of density?
the amount of matter in a given volume
word equation for density
density= mass/volume
symbol equation for density
p= m/V
what are some common units for density?
kg/m3 or g/cm3
what is particle model used for?
the idea that solids, liquids and gases are made up of particles
draw a particle diagram for solids, liquids and gases
Solid- packed together in an order
Liquid- packed together randomly
Gas- free to move and spaced out
How do you find the volume of a regular solid?
measure the length, width and height of object and times together
(to find density do the above and then put the object on the balance- equation p=m/V)
How do you find the volume of an irregular solid?
Put object on balance- mass
Fill a displacement can with water
Put irregular object into displacement can with measuring cylinder under the spout and measure the amount of water goes into the cylinder to find the volume
find density = mass/volume
what equipment could be use to measure length to a more precise value?
a micrometer
when is mass conserved?
Always during changes of state
e.g: Melting freezing, subliming etc…
what makes a change of state different to a chemical change?
Change of state are physical changes, so the material will recover to its original properties if the change is reversed
what is internal energy?
the total kinetic energy and potential energy stored inside a system by the particles (atoms and molecules) that make up the system
how does heating an object change the internal energy?
it increases the energy of the particles
what does the increase in temperature of a system depend on?
the mass of the substance
the type of material
the energy input
equation that relates the change in thermal energy of a system to the factors that it depends on?
change of thermal energy= mass x specific heat energy x temperature change
