In which of one the following all the concentration terms are independent of temperature?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → mole fraction, mass fraction, molality
Let’s analyze each concentration term:
- Molarity (M) – moles of solute per liter of solution → depends on volume, which changes with temperature → temperature dependent
- Molality (m) – moles of solute per kg of solvent → depends on mass, independent of temperature
- Mole fraction (x) – ratio of moles → depends on number of moles, independent of temperature
- Mass fraction (w) – ratio of masses → independent of temperature
- ppm – parts per million by mass or volume → mass-based ppm is independent, volume-based is temperature dependent
Terms independent of temperature:
- Molality
- Mole fraction
- Mass fraction
Hence, OPTION 4 IS CORRECT