Question

$ CaC{{l}_{2}} $ is preferred to $ NaCl $ for clearing ice on roads particularly in very cold countries. This is because

• A. $ CaC{{l}_{2}} $ is less soluble in $ {{H}_{2}}O $ than $ NaCl $
• B. $ CaC{{l}_{2}} $ is hygroscopic but $ NaCl $ is not
• C. eutectic mixture of $ CaC{{l}_{2}}\text{/}{{H}_{2}}O $ freezes at $ -\ 55{}^\circ C $ while that of $ NaCl\text{/}{{H}_{2}}O $ freezes at $ -18{}^\circ C $
• D. $ NaCl $ makes the road slippery but $ CaC{{l}_{2}} $ does not

Answer 1

Answer: (C)

$ CaC{{l}_{2}} $ is preferred to $ NaCl $ for clearing ice on roads particularly in very cold countries. This is because eutectic mixture of $ CaC{{l}_{2}}\text{/}{{H}_{2}}O $ freezes at a much lower temperature $ -\,55{}^\circ C $ while that of $ NaCl\text{/}{{H}_{2}}O $ freezes at $ -\,18{}^\circ C $