Topic 1

Question 1

What is Doltons model of atam

Answer 1

1803 - Dalton believed that all substances were made from atoms
Atoms can’t be created divided or destroyed
Atoms of same element are exactly alike
Atoms join with other Atoms to make new substances

Question 2

What was Thompson model of atom

Answer 2

1897 Plum pudding model - Thompson believe that atoms had negative electrons scattered through soft blobs of positively charged material

Question 3

What was Rutherfords model of the atom

Answer 3

1909 - shot a beam of positively charged particles at gold foil
The atoms mostly went straight through
Same bounced back or rebounded
He then believed that electrond travelled in random paths around the nucleus

Question 4

How to calculate relative atomic mass

Answer 4

(Mass number of isotope one x percentage abundance of isotope one )
+
+ ( mass number of isotope 2 × percentage abundance of isotope 2)

÷ 100

Question 5

How did mendeleev order the elements in his atomic table

Answer 5

He ordered them in order of atomic mass
He then left gaps for elements he hadn’t discovered yet

Question 6

How was mendeleev able to predict the existence and properties of elements not yet discovered?

Answer 6

Mendeleev realised that elements with similar properties we in the same groups in the periodic table so was able to leave gaps and place the discovered elements where they fit best