The formula for molality---> m = moles solute/ Kg of solvent
the solute here is NH₃ because it's the one with less amount. which makes water the solvent.
1) let's convert the grams of NH₃ to moles using the molar mass
molar mass of NH₃= 14.0 + (3 x 1.01)= 17.03 g/ mol
15.0 g (1 mol/ 17.03 g)= 0.881 mol NH₃
2) let's convert the grams of water into kilograms (just divide by 1000)
250.0 g= 0.2500 kg
3) let's plug in the values into the molality formula
molality= mol/ Kg---> 0.881 mol/ 0.2500 kg= 3.52 m
Answer: The correct answer is: [B]:
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" organic acid and amines " .
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<u>Note</u>: Choice B: "organic acid and amines" ;
is the only answer choice that contains "amines" (hint: <u> amin</u><u>o acid</u> / <u>amin</u><u>e)</u> ; which are "proteins" .
As such; Choice "B" is the <u><em>only</em></u> correct answer choice.
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Hope this helps!
Best wishes to you!
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Data:
M (molarity) = 1.75 M (mol/L)
m (mass) = 35 g
MM (molar Mass) of NaCl = 58.44 g/mol
V (volume) = ? (in liters)
Formula:

Solving:





Answer:
There's a very small difference between the two...a compound is when you mix several elements to create a whole new one. A mixture is when you mix several elements together, but instead of it creating a completely different compound, it's simply just a few elements mixed together.
For a closed system, you need two things:
1) a conservation of mass within the boundaries of the system
2) the ability to freely exchange energy to & from the "closed" system with a surrounding external system
So, the answer is <u><em>never</em></u>, since your defining the "system" as the water within the bathtub, and an open bathtub is exposed to evaporation, which is not conserving mass within the defined "system".