In: Biology
Solution C is 300 mL of 0.2 M NaCl
Molecular weight of NaCl is 58.44 g/mol.
1 M NaCl has 58.44 g/1000 ml
0.2 M NaCl has 11.688 g/1000 ml (58.44 x 0.2)
0.2 M NaCl has 3.5064 g/300 ml (11.688 x 300/1000 = 3.5064)
So, solution C has 3.5064 g of NaCl.
Solution D is 500 mL of 0.6 M NaCl.
1 M NaCl has 58.44 g/1000 ml
0.6 M NaCl has 35.064 g/1000 ml (58.44 x 0.6)
0.2 M NaCl has 17.532 g/500 ml (35.064 x 500/1000 = 17.532).
So, solution D has 17.532 g of NaCl.
After 24 hours, both solution C and D will have equal volume of water and equal concentration of NaCl, as the membrane is permeable to water, Na+, and Cl- ions.
Total volume is 800 ml (300+500). So, each solution would have 400 ml.
Total quantity of NaCl is 21.0384 g (3.5064 + 17.532) in 800 ml. This means 0.45 M concentration.
800 ml has 21.0384 g NaCl (i.e. 26.298 g/L).
If 1 M NaCl has 58.44 g/1000 ml, then the concentration of the solution at 26.298 g/L is 0.45 M (26.298/58.44 = 0.45).