Asolution is prepared by adding .8 g of iron sulfate to 450ml of water
calculate the effective molality of the solution'

Molar mass FeSO₄ =151.908 g/mol

Volume = 450 mL / 1000 = 0.45 L

1 mol 151.908 g
n mol 0.8 g

n = 0.8 * 1 / 151.908

n = 0.00526 moles 

M = n / V

M = 0.00526 / 0.45

M = 0.01168 mol/L⁻¹

hope this helps!

Spontaneity tell us the direction of the reaction, but not how fast it goes. gibbs free energy brings together enthalpy, entropy and temperature in one easy formula. g = h - ts. and, finally the sign of delta g is always negative for a spontaneous reaction.