371. mg of an unknown protein are dissolved in enough solvent to make 5.00 ml of solution. the osmotic pressure of this solution is measured to be at 0.118 atm at 25 c
calculate the molar mass of the protein.

The molar mass of the protein is 15394.2 g/mol

Explanation:

To calculate the concentration of solute, we use the equation for osmotic pressure, which is:

where,

= osmotic pressure of the solution = 0.118 atm

i = Van't hoff factor = 1 (for non-electrolytes)

M = molarity of solute = ?

R = Gas constant =

T = temperature of the solution =

Putting values in above equation, we get:

To calculate the molecular mass of solute, we use the equation used to calculate the molarity of solution:

We are given:

Molarity of solution =

Given mass of protein = 371. mg = 0.371 g   (Conversion factor:  1 g = 1000 mg)

Volume of solution = 5.00 mL

Putting values in above equation, we get:

Hence, the molar mass of the protein is 15394.2 g/mol

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.

a) the particles of the chair are strongly held together.