Question:
The low solubility of LiF and that of CsI in water are respectively due to which of the properties of the alkali metal ions?
The low solubility of LiF and that of CsI in water are respectively due to which of the properties of the alkali metal ions?
Show Hint
Small ions → high lattice enthalpy
Large ions → low hydration enthalpy
Both can reduce solubility
Updated On: May 2, 2026
- higher hydration enthalpy of Li$^+$, higher lattice enthalpy of Cs$^+$
- smaller hydration enthalpy of Li$^+$, higher lattice enthalpy of Cs$^+$
- smaller lattice enthalpy of Li$^+$, higher hydration enthalpy of Cs$^+$
- smaller hydration enthalpy of Li$^+$, smaller lattice enthalpy of Cs$^+$
- higher lattice enthalpy of Li$^+$, smaller hydration enthalpy of Cs$^+$
Show Solution
Verified By Collegedunia
The Correct Option is
Solution and Explanation
Concept: Solubility depends on two competing factors
• Lattice enthalpy (energy required to break ionic solid)
• Hydration enthalpy (energy released when ions dissolve)
Step 1: LiF case
• Li$^+$ is very small → strong electrostatic attraction
• Hence, LiF has very high lattice enthalpy
• Even though hydration enthalpy is high, lattice enthalpy dominates
• Therefore, LiF is poorly soluble
Step 2: CsI case
• Cs$^+$ is very large → weak interaction with water
• Hence, hydration enthalpy is small
• So dissolution is not favored
• Therefore, CsI is also poorly soluble Final Answer: \[ \boxed{\text{(E)}} \]
• Lattice enthalpy (energy required to break ionic solid)
• Hydration enthalpy (energy released when ions dissolve)
Step 1: LiF case
• Li$^+$ is very small → strong electrostatic attraction
• Hence, LiF has very high lattice enthalpy
• Even though hydration enthalpy is high, lattice enthalpy dominates
• Therefore, LiF is poorly soluble
Step 2: CsI case
• Cs$^+$ is very large → weak interaction with water
• Hence, hydration enthalpy is small
• So dissolution is not favored
• Therefore, CsI is also poorly soluble Final Answer: \[ \boxed{\text{(E)}} \]
Was this answer helpful?
0
0
Top KEAM Chemistry Questions
- The pH of a solution obtained by mixing 60 mL of 0.1 M BaOH solution at 40m of 0.15m HCI solution is
- $4\, g$ of copper was dissolved in concentrated nitric acid. The copper nitrate solution on strong heating gave $5\, g$ of its oxide. The equivalent weight of copper is :
- Green chemistry deals with
- Neopentyl bromide undergoes dehydrohalogenation to give alkenes even though it has no $\beta$- hydrogen. This is due to
- Plot of $ log\text{ }x/m $ against log $p$ is a straight line inclined at an angle of $ 45{}^\circ $ . When the pressure is $ 0.5 \,arm $ and Freundlich parameter. $ k $ is $ 10 $ , the amount of solute adsorbed per gram of adsorbent will be $ (log\text{ }5=0.6990) $
View More Questions
Top KEAM Ionic Equilibrium In Solution Questions
- The correct equation for the degree of association $'\alpha'$ of an associating solute, $'n'$ molecules of which undergoes association in solution, is
- Which of the following can act as Lewis acid?
- The concentration of hydrogen ions in a sample of soft drink is \( 2\times10^{-4}\,\text{mol L}^{-1} \). Its pH value is ( \( \log 2 = 0.3010 \) )
- The concentration of hydrogen ions in a hydrochloric acid solution is $3 \times 10^{-3}M$. Its pH value is about ($\log 3 = 0.4771$)
- A monobasic acid HA has pH of 3 in 0.1 M solution at 298 K. What is the pKa of the acid at 298 K?
View More Questions
Top KEAM Questions
- i.$\quad$ They help in respiration ii.$\quad$ They help in cell wall formation iii.$\quad$ They help in DNA replication iv. $\quad$They increase surface area of plasma membrane Which of the following prokaryotic structures has all the above roles?
- A body oscillates with SHM according to the equation (in SI units), $x = 5 cos \left(2\pi t +\frac{\pi}{4}\right) .$ Its instantaneous displacement at $t = 1$ second is
- The pH of a solution obtained by mixing 60 mL of 0.1 M BaOH solution at 40m of 0.15m HCI solution is
Kepler's second law (law of areas) of planetary motion leads to law of conservation of
- If $\int e^{2x}f' \left(x\right)dx =g \left(x\right)$, then $ \int\left(e^{2x}f\left(x\right) + e^{2x} f' \left(x\right)\right)dx =$
View More Questions