Answer: 0.028 grams
Explanation:
Depression in freezing point :
Formula used for lowering in freezing point is,
or,
where,
= change in freezing point
= freezing point constant (for benzene} =
m = molality
Putting in the values we get:
0.028 grams of DDT (solute) must be dissolved in 209.0 grams of benzene to reduce the freezing point by 0.400°C.
Answer:
See below
Step-by-step explanation:
You won't see much happening. The solution is saturated, so the salt will fall to the bottom of the container and sit there. It will not dissolve.
However, at the atomic level, Na⁺ and Cl⁻ ions are being pulled from the surface of the crystals and going into solution as hydrated ions. At other places, Na⁺ and Cl⁻ ions are returning to the surface of the crystals.
The process is
NaCl(s) ⇌ Na⁺(aq) + Cl⁻(aq)
The rates of the forward and reverse processes are equal, so you see no net change.
Multiple states of matter - mixture
Same state of matter - pure
Separated physically- mixture
Consistent properties - pure
Can’t be separated- pure
Can’t be a single element - mixture
Bromine has one more electron shell than the chlorine atom making the radius larger than the chlorine atom.
First let us calculate for the molar mass of ibuprofen:
Molar mass = 13 * 12 g/mol + 18 * 1 g/mol + 2 * 16 g/mol
Molar mass = 206 g/mol = 206 mg / mmol
Calculating for the number of moles:
moles = 200 mg / (206 mg / mmol)
moles = 0.971 mmol = 9.71 x 10^-4 moles
Using the Avogadros number, we calculate the number of
molecules of ibuprofen:
Molecules = 9.71 x 10^-4 moles * (6.022 x 10^23 molecules
/ moles)
<span>Molecules = 5.85 x 10^20 molecules</span>
