Answer:
magnesium= +2
aluminum= +3
phosphorous= -3
lithium= +1
fluorine= -1
Explanation:
As fluorine having seven valance electrons in its outer most shell with atomic number nine. And for completing its outer most shell it needs one more electron that is why it form ion of -1 value.
Now Aluminum has three electrons in its outer most shell with atomic number 13. So it need to lose these three electrons in order to be in stable state that is why it have ion in +3 state.
Same rule apply for other elements too.
we have
work done (W)= force(F) × displacemen(s)
or, 80= F× 8
or, F= 10 N
therefore, 10 N force is required to lift the rock.
Answer: 1 mole of the substance is equal to its molar mass or vice versa.
Explanation: Example: 18 g H2O x 1 mole H2O / 18g H2O = 1 mole H2O