Answer:
0.38
Explanation:
Molar mass of thiophene= 84g/mol
Mass of thiophene = 37g
Number of moles= 37/84= 0.44 moles
Molar mass of heptane= 100 g/mol
Mass of heptane = 72g
Number of moles = 72/100= 0.72 moles
Total number of moles= 0.44 + 0.72= 1.16 moles
mole fraction of thiophene = 0.44/1.16= 0.38
Answer:
136.63 °C
Explanation:
ΔTb=Tb solution - Tb pure
Where; Tb pure = 133.60°C
molar mass of solute = 121.14 g/mol
number of moles of solute; 52.2g/121.14 g/mol = 0.431 moles
molality = 0.431 moles/350 * 10^-3 = 1.23 molal
Then;
ΔTb = Kb * m * i
Kb = 2.46°C kg mol^-1
m = 1.23 molal
i = 1
ΔTb = 2.46 * 1.23 * 1
ΔTb = 3.03 °C
Hence;
Tb solution = ΔTb + Tb pure
Tb solution = 3.03 °C + 133.60°C
Tb solution = 136.63 °C
Most tennis balls are usually hollow, while golf balls are not. Therefore a golf ball contains more mass.
Hope this helps!
Number one is physical change the other one is chemical change
