What would the final boiling point of water be if 3 mol of nacl were added to 1 kg of water (k b =0.51^ c/(mol/kg) for water and j = 2 for nacl)? a. 98.47° c b. 101.53° c c. 96.94° c d. 103.06°c

Explanation:

The normal boiling point of water at 1 atm is . When a salt is dissolved in a solvent, in this case water, it increases the boiling point of that solvent. The final boiling point can be calculated using the boiling point elevation formula which states that:

Here:

is the change in the boiling point, defined as:

That is, the difference between the final boiling point and the initial boiling point (100 degrees Celsius);

is known as the van 't Hoff factor, in case we have a non-electrolyte/non-ionic substance, it's equal to 1, however, NaCl (aq) dissociates into 1 mole of sodium and 1 mole of chloride ions, so we have a total of 2 moles of ions per 1 mole of NaCl (aq), meaning i = 2, as the problem states;

is known as the boiling point elevation constant for the solvent;

is the molality of substance, which is found dividing moles of solute by the kilograms of solvent:

Therefore, we obtain:

Solving for the final boiling point, add the initial temperature to both sides of the equation:

Substitute the given variables:

a gas, having a molecular weight of 13 kg/kmol and a kinematic viscosity of 0.25 cm2/s, flows through a pipe 0.25 m internal diameter and 5 km long at the rate of 0.4 m3/s and is delivered at atmospheric pressure.

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.