Particle model matter

Question 1

Why do liquids and solids normally have a high density?

Answer 1

Because lots of particles are closely packed together, they normally have a higher mass for their volume.

Question 2

What is a density of a material?

Answer 2

the amount of mass packed into a certain volume, e.g a brick has a high density and something like a polystyrene block has a low density because it has a low mass packed into a certain volume

Question 3

What does the pressure of a gas depend on in a container?

Answer 3

The amount of times the particles collide with the walls of the container the gas is held in, when the particles collide with the walls it exerts pressure.

Question 4

How do you increase the pressure of a gas?

Answer 4

Increase the temperature

Question 5

How does the temperature increase lead to an increase of pressure?

Answer 5

The increase in temperature leads the a higher amount of kinetic energy in the particle collisions, the higher energy and more frequent collisions leads to a higher temperature because more pressure is being exerted.

Question 6

What is the radius of an atom?

Answer 6

1 x 10^-10

Question 7

What charge are protons

Answer 7

positive

Question 8

what charge are electrons

Answer 8

negative

Question 9

what charge are neutrons

Answer 9

neutral

Question 10

How does the distance of the energy level (shell) change the amount of energy it has?

Answer 10

An energy level which is further has more energy and one that is closer has less energy

Question 11

How can electrons change energy levels?

Answer 11

When they gain electromagnetic radiation it moves up an energy level, when it emits that electromagnetic radiation it can move back down an energy level

Question 12

What does the mass number tell you?

Answer 12

The number of protons and neutrons

Question 13

what does the atomic number tell you

Answer 13

the number of protons

Question 14

What are isotopes?

Answer 14

when an element has the same number of protons as another atom of the same element but a different amount of neutrons

Question 15

What charge does an ion have when it loses and gains an electron?

Answer 15

loss = +1 charge 
gain = -1 charge

Question 16

What was the plum pudding model?

Answer 16

The idea that atoms are a ball of positive charge with negative electrons imbedded in it

Question 17

What did the alpha scattering experiment show?

Answer 17

The fact that most the alpha particles passed through the thin gold foil showed that the alpha particle was mainly empty space. the fact that some were deflected showed that the alpha particle must therefore have a positive charge. the fact that some alpha particles bounced back showed that the atoms must have a concentrated centre.