Answer:

Explanation:
= First mass of water = 12 oz
= Second mass of water = 20 oz
= Temperature difference of the solution with respect to the first mass of water =
= Temperature difference of the solution with respect to the second mass of water = 
c = Specific heat of water
As heat gain and loss in the system is equal we have

The final temperature of the solution is
.
That is true b<span>ecause 1 nanometer = 1.0 × 10^-15 megameters.</span>
The freezing point depression can be explained in terms of vapor pressure adding solvent will decrease molecules
given days = 42 days
So, number of half life, n = 42/14.3 = 2.93
So, after 42 days, the mass of sodium phosphate sample left = original mass
x (1/2)^n,
= 157 mg x (1/2)^2.93 = 20.60 g of Na3PO4 after 42 days
Formula mass of Sodium phosphate = 3(23) + 32 + 4(16) amu = 165 amu
165 g of sodium phosphate contains 32 g of Phosphorus
20.60 g ------------------------------? = 20.60 x 32/ 165 =3.99g of P32