C1-key Concepts In Chemistry

Question 1

Neutrons relative mass,relative charge,location

Answer 1

Relative mass 1
Relatice charge 0
In the nucleus

Question 2

Electron relative mass ,relative charge

Answer 2

0.0005=relative mass

Relative charge=-1

Question 3

Proton relative mass ,relative charge

Answer 3

Relative mass 1

Relative charge +1

Question 4

What is plum pudding model

Answer 4

Electrons are randomly distributed in a sphere of positive charge

Question 5

The gold foil experiment

Answer 5

They fire an alpha partice which has a large postive charge +2 at a thin sheet of gold

Question 6

RUTHERFORDS EXPERIMENTAL CONCLUSIONS

Answer 6

Path A suggests-most of atom is empty
Path B suggests-atoms have a nucleus which is postivd (so repels alpha particles)
Path c suggests -this nucleus is very small and in the centre of the atom

Question 7

Bohrs nuclear model

Answer 7

There is a tiny central positively charged nucleus that contains most of the atoms mass

Most of an atom is empty space

Electrons aren’t in a “cloud” the are in fixed orbits called energy level or electron shell

Question 8

We now know that an atom approximately…

Answer 8

10 to the power of -10 in radius

Question 9

What does the atomic number tell us

Answer 9

The number of proton in nucleus

Question 10

Are elements neutral or not neutral and what does this

Answer 10

Elements are neutral -this means they have equal number of protons and electrons

Question 11

The number of neutrons in an element is equal to

Answer 11

Mass number -atomic number

/big number -little number