If 0.5 L of solution contains 4 mol
then let 1 L of solution contain x mol
⇒ (0.5 L) x = (4 mol) (1 L)
x = (4 mol · L) ÷ (0.5 L)
x = 8 mol
Thus the molarity of the Sodium Chloride solution is 8 mol / L OR 8 mol/dm³.
M P₂O₅ = 31g×2 + 16g×5 = 142g/mol
1 mole of P₂O₅ contains 5 moles of atoms
5 moles of atoms = 30,01×10²³ a.
142g ----------- 30,01×10²³ a.
0,69g ---------- X
X = (0,69×30,01×10²³)/142
X = 0,14626×10²³ = 1,4626×10²² atoms
:)
The CNS {central nervous system}
