atoms/ions basics- Chemistry

Question 1

when atoms gain or lose electrons they become what ?

Answer 1

ions

Question 2

what are isotopes ?

Answer 2

different versions of an element

Question 3

who came up with the plum pudding model and what did they theorise ?

Answer 3

J.J. Thompson - positively charged sphere, negatively charged electrons dotted throughout

Question 4

electrons orbit the nucleus through set distances - who came up with this theory ?

Answer 4

Niels Bohr

Question 5

what is the formula for working out the average mass of an element which has isotopes ?

Answer 5

(% of isotope 1 ) (% of isotope 2 relative atomic mass of)
(——————— x relative atomic mass of isotope 2) + (——————— x isotope 2 )
( 100 ) ( 100 )

Question 6

what is the Center of an atom called

Answer 6

the nucleus

Question 7

give the definition of a molecule

Answer 7

more than one atom chemically bonded together

Question 8

true or false: everything is made of atoms

Answer 8

true

Question 9

what are the subatomic particles

Answer 9

protons, neutrons, electrons

Question 10

true or false: atoms cannot be created nor destroyed

Answer 10

true

Question 11

what is relative atomic mass ?

Answer 11

the mass of 1 atom compared to a hydrogen atom - it doesn’t have any units

Question 12

give the definition of a compound

Answer 12

more than 1 type of atom chemically bonded together

Question 13

who discovered isotopes ?

Answer 13

James Chadwick

Question 14

why do atoms want to lose electrons ?

Answer 14

so that all of their shell that have electrons in them are full and therefore they would be stable

Question 15

what are the rules of electron arrangement shells ?

Answer 15

up to 2 go into the first shell
once that is full, up to 8 go into the second
once that one is full, up to 8 go into the third

Question 16

what is the deference between a compound and an element

Answer 16

a compound cannot be the same type of element

Question 17

true or false:
in an isotope there is the same number of protons and neutrons

Answer 17

false: different number

Question 18

what does the law of conversation of mass state ?

Answer 18

in a chemical reaction, the mass of the products are the same as the mass of the reactants

Question 19

who did the alpha particle gold leaf scattering experiment and what did they theorise ?

Answer 19

Ernest Rutherford - the nucleus of atoms were extremely dense, atoms were mostly empty space

Question 20

finish the sentence:
in an atom, the number of protons is the same as the number of ____________

Answer 20

electrons

Question 21

how do atoms differentiate from other atoms

Answer 21

the number of protons determines what element it is