Question

Gallium (Ga, 69.723 g/mol) is a metalloid obtained from its salts during the smelting of ores of other elements, like Zinc. has broad applicability in the electronics industry. It is also used as a safe replacement for mercury in thermometers as it melts at 29.8 °C and has a heat of fusion of 5.59 kJ/mol. What is the entropy change of 22 g of gallium in J/K as it melts when placed on a surface at 29.8°C?

Answer 1

4.255 J/ K

Step-by-step explanation:

Given data :

mass of Gallium = 16 gm

molar mass = 69.723 g/mol

hence no of moles = 16 / 69.723 = 0.23 moles --------- ( 1 )

Δh ( heat fusion ) = 5.59 KJ/mol

Temperature = 29.8°C = 302.8 k

Determine the entropy change of gallium

Δs ( entropy change ) = heat fusion / temperature

= ( 5.59 * 1000) J/mol / 302.8 = 18.46 J/k*mol

Hence entropy change of gallium

= Δs * no of Gallium moles

= 18.46 * 0.23 = 4.255 J/ k

I hope this is right haha