Particle models (heating etc) (topic 14) Flashcards
What is the definition of specific heat capacity?
the energy required to raise the temperature of 1 kg of a substance by 1’C
What is the equation to work out energy required to heat an object by a certain degree
mass x specific heat capacity x temperature change
What is the equation of density and definition?
mass/volume
the mass of a certain volume of substance
What happens to density when an object increases in temperature?
Density decreases
What happens to the pressure when the volume of the same mass increases?
Decreases because the particles have more room
What is absolute 0?
-273 Celsius or 0 kalvin
How do you convert from Celsius to kalvin?
+273
What is the equation to work out pressure?
force/area
WHat is the equation for working out pressure of a fluid?
height x density x 9.81
What is upthrust ?
the difference between the pressure above and the pressure below
What is the atmospheric pressure?
100,000 pascals
What is the unit of pressure?
pascals
What is elastic deformation?
When an object will return to its original shape after being stretched
inelastic deformation?
when an object wont return to its original shape after being deformed
how do you work out force on a spring?
spring constant x extention
What does the gradient of a force extension graph show?
its the spring constant
How do you work out the energy transferred in stretching?
0.5 x spring constant x extension2
What is latent heat?
The heat energy that is taken in or given out by a substance when it changes state
What is the equation to work out specific latent heat?
mass x specific heat capacity
What did j.j Thomson do to progress the atomic model?
He discovered electrons with cathode rays. He was the first scientist to show that atoms are made of smaller sub atomic things. He came up with t.he plum pudding model
What did Ernest Rutherford do to progress the atomic model?
Published results from his gold leaf experiment which consisted of firing a beam of alpha particles at a thin piece of gold. He found many particle bounced back leading him to decide there has to be a very dense nucleus at the centre.
What did James Chadwick to do progress the atomic model?
He showed that gamma radiation could be explained by a neutral particle. He performed numerous experiments, bombarding elements with these particles. From this he was able to measure the mass of this neutral particle. He called it a neutron.
What is the relative atomic mass?
the number of protons + neutrons
What is the atomic number?
Number of protons
What is the emission spectrum?
It is a spectrum of light caused by electrons in excited (high energy) gases moving up an energy level and then moving back down to a more stable level by releasing light.
what is the absorption spectrum?
Some of the light emitted from emission spectra is absorb by gases in the atmosphere of the star, from this we can work out what gases are in that stars atmosphere.
