paper 1 knowlege gaps

Question 1

bond breaking is

Answer 1

endothermic

Question 2

bond forming is

Answer 2

exothermic

Question 3

how to calibrate a ph probe

Answer 3

wash probe
put in calibration buffer and adjust ph reading
repeat in different solution if needed
wash probe between solutions

PRECISE TO 2D.P

Question 4

acid + metal hydroxide —>

Answer 4

salt + water

Question 5

purification is electrolysis

Answer 5

metal at both electrodes
at cathode is pure
at anode is impure , the impurites can be collected underneath the anode

Question 6

relative atomic mass

Answer 6

mean mass compared to one mass of an atom of an element compared to 1/12 mass of carbon-12 atom

Question 7

relative formula mass

Answer 7

mean mass do à unit of substance compared to 1/12 mass of carbon-12

Question 8

relative molecular mass

Answer 8

mean mass of molecule compared to 1/12 mass of carbon 12 atom

Question 9

meaning of avogadros constant

Answer 9

number of entities in one mol

Question 10

metal oxides are

Answer 10

alkaline

Question 11

non metal oxides are

Answer 11

acidic

Question 12

bondifn in simple covalent molecules

Answer 12

covalent bond between atoms are strong
intermolecular forces between MOLECULES are weak