Answer:
D
Explanation:
a city would first need to know the cost and benefits
The first one is 2
The second is 1
The third is 6
And the fourth is 3
Answer:
15.5 gm
Explanation:
What is the mass of phosphorus that contains twice the number of atoms found in 14 g of iron?
[Relative atomic mass : P = 31; Fe = 56]
14 gm Fe = 14gm/ 56 gm/mole = 14 mole gm/56gm = 14/56 mole
0.25 moles
2 X 0.25 = 0.5 moles
1 mole P = 31 gm
so
0.5 moles P =31/2 =15.5 gm
Neither of them are used in magnets they don’t attract metal
