suppose that a 125 ml flask is found to have a total volume of 139 mL. How many moles of vapor will fill this flask at a pressure of 760 Torr and a temperature of 100 C

4.54×10¯³ mole

Explanation:

The following data were obtained from the question:

Volume (V) = 139 mL

Pressure (P) = 760 torr

Temperature (T) = 100 °C

Number of mole (n) =.?

Next, we shall determine convert 139 mL to litre (L). This can be obtained as follow:

1000 mL = 1 L

Therefore,

139 mL = 139 mL / 1000 mL × 1 L

139 mL = 0.139 L

Therefore, 139 mL is equivalent to 0.139 L

Next, we shall convert 760 torr to atm.

This can be obtained as follow:

760 torr = 1 atm

Next, we shall convert 100 °C to Kelvin temperature. This can be obtained as follow:

Temperature (K) = Temperature (°C) + 273

Temperature (°C ) = 100 °C

Temperature (K) = 100 °C + 273

Temperature (K) = 373 K

Finally, we shall determine the number of mole of the vapor as follow:

Volume (V) = 0.139 L

Pressure (P) = 1 atm

Temperature (T) = 373 K

Gas constant (R) = 0.0821 atm.L/Kmol

Number of mole (n) =.?

PV = nRT

1 × 0.139 = n × 0.0821 × 373

Divide both side by 0.0821 × 373

n = (1 × 0.139) / (0.0821 × 373)

n = 4.54×10¯³ mole

Therefore, 4.54×10¯³ mole of vapor will fill the flask.

Answer is Option-3:
                               C₆H₁₄ (Hexane) and H₂O are immiscible.

Explanation:
                   Hexane is a chain of six carbon atoms attached to each other in straight chain and hydrogen atoms. All the bonds in this compound are non-polar. Hexane molecules interact with each other through London Dispersion Forces.
                  While, Water molecules are polar in nature, due to electronegativity difference between Oxygen and Hydrogen atoms the Hydrogen atom is partially positive and Oxygen atom is partially negative. And water molecles interact with each other through hydrogen bonding.

 Result:
                As we know LIKE DISSOLVES LIKE, so both Hexane and water are different from each other, so when mixed together thay fail to develop interactions with each other, Hence immiscible in each other.