For calculating which pair of solution is isotonic...we have to equal their osmotic pressure...means (pie1 = pie2) and (pie = iCRT) where... (i = vant hoff factor , C= concentration, R= solutions constant , T= temperature)...and u should also given question at same temperatures...then we can calculate it...because if in question temperature given is same then...RT is constant...so we can equally pie1 and pie2 calculate isotonic pair.


$$Hope it's help... $$

Isotonic Solutions

Isotonic solutions are solutions that have the same osmotic pressure. Osmotic pressure is the pressure required to prevent the flow of water across a semipermeable membrane due to a difference in solute concentration. In other words, isotonic solutions have the same concentration of solutes.

Determining Isotonic Solutions

To determine whether a pair of solutions is isotonic, we need to compare their concentrations. The solution with a higher concentration of solutes will have a higher osmotic pressure and will be hypertonic, while the solution with a lower concentration of solutes will have a lower osmotic pressure and will be hypotonic.

If two solutions have the same concentration of solutes, they will have the same osmotic pressure and will be isotonic.

Comparing the Given Solutions

Let's compare the given pairs of solutions to determine which ones are isotonic:

a) 0.01 M CaCl2 and 0.001 M NaCl
- The concentration of CaCl2 is 0.01 M, while the concentration of NaCl is 0.001 M.
- The solution with CaCl2 has a higher concentration of solutes, so it is hypertonic.
- The solution with NaCl has a lower concentration of solutes, so it is hypotonic.
- Therefore, this pair of solutions is not isotonic.

b) 0.001 M Al2(SO4)3 and 0.01 M BaCl2
- The concentration of Al2(SO4)3 is 0.001 M, while the concentration of BaCl2 is 0.01 M.
- The solution with BaCl2 has a higher concentration of solutes, so it is hypertonic.
- The solution with Al2(SO4)3 has a lower concentration of solutes, so it is hypotonic.
- Therefore, this pair of solutions is not isotonic.

c) 0.001 M CaCl2 and 0.001 M Al2(SO4)3
- Both solutions have the same concentration of solutes (0.001 M).
- Since they have the same concentration, they will have the same osmotic pressure and are isotonic.
- Therefore, this pair of solutions is isotonic.

d) 0.01 M BaCl2 and 0.001 M CaCl2
- The concentration of BaCl2 is 0.01 M, while the concentration of CaCl2 is 0.001 M.
- The solution with BaCl2 has a higher concentration of solutes, so it is hypertonic.
- The solution with CaCl2 has a lower concentration of solutes, so it is hypotonic.
- Therefore, this pair of solutions is not isotonic.

Conclusion

The pair of solutions that is isotonic is c) 0.001 M CaCl2 and 0.001 M Al2(SO4)3. This is because they have the same concentration of solutes and therefore the same osmotic pressure.