1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Rama09 [41]
3 years ago
15

25 g of a compound is added to 500 mL of water if the freezing point of the resulting solution is

Chemistry
1 answer:
vlabodo [156]3 years ago
5 0

Answer:

a)   119 g/mol

Explanation:

-We apply the formula for freezing point depression to obtain the molality of the solution:

\bigtriangleup T_f=K_fm, \  \ K_f=1.36\textdegree C/m\\\\\therefore m=\frac{\bigtriangleup T_f}{K_f}\\\\=\frac{0.57\textdegree C}{1.36\textdegree C}\\\\=0.4191\ mol/Kg\\\\

#We use the molality above to calculate the molar mass:

m=\frac{0.4191\ mol}{1\ Kg}=\frac{25\ g}{0.5\ Kg}\\\\\therefore 1 \ mol=\frac{25\ g}{0.5\ Kg}\times\frac{1\ Kg}{ 0.4191}\\\\=119.3033\approx 119\ g/mol

Hence, the molar mass of the compound is 119 g/mol

You might be interested in
After 1911, most scientists accepted the theory that nucleus of an atom was very dense and very small and has a positive charge.
Yanka [14]
After 1911 most scientists accepted<span> the </span>theory<span> that the </span>nucleus<span> of an </span>atom<span> was </span>very dense<span> and </span>very small<span> and </span>has<span> a </span>positive charge<span>. </span>
8 0
3 years ago
At 500 K, the reaction is at equilibrium with the following concentrations. [PCI5]= 0.0095 M [PCI3] = 0.020 [CI2] = 0.020 M What
Ad libitum [116K]
Although it is omitted, the reaction equation for the decomposition of phosphorus pentachloride is:
PCl₅ → PCl₃ + Cl₂

The equilibrium constant's equation then becomes:
Kc = [PCl₃]*[Cl₂] / [PCl₅]
Kc = (0.02 * 0.02) / 0.0095
Kc = 0.042

The equilibrium constant is 0.042.
8 0
2 years ago
Read 2 more answers
Can anyone give me the name of these? 40 points. Hope it's not too much
kolbaska11 [484]
1. 5 ethyl, 2 methyl octane
2. 1 ethyl, 2 methyl cyclopentane
3. 3,3,5,5- tetrafluoro heptane
4. 3,4-dimethyl hexene
5. 3,4-dimethyl cyclobutene
6. 3,5 diisopropyl cyclohexene
7. 3,3,4 trimethyl pentyne
8. 2,6 dibromo phenol

keep in mind that between 4-7, there could be #1 in front of the main name. for example with #4: 3,4-dimethyl-1- hexene. this honestly depends on the professor how he/she likes it. It is not necessary because if the number is not specified, it is assumed is #1
4 0
3 years ago
A student measures a mass of an 8cm3 block of brown sugar to be 19.9G. what is the density of the brown sugar?
Naily [24]

Answer:

<h2>2.49 g/cm³</h2>

Explanation:

The density of a substance can be found by using the formula

density =  \frac{mass}{volume} \\

From the question we have

density =  \frac{19.9}{8}  \\  = 2.4875

We have the final answer as

<h3>2.49 g/cm³</h3>

Hope this helps you

3 0
2 years ago
Calculate the number of milliliters of 0.440 M KOH required to precipitate all of the Fe2+ ions in 187 mL of 0.692 M FeSO4 solut
EleoNora [17]

Answer:

588.2 mL

Explanation:

  • FeSO₄(aq) + 2KOH(aq) → Fe(OH)₂(s) + K₂SO₄(aq)

First we <u>calculate how many Fe⁺² moles reacted</u>, using the given <em>concentration and volume of FeSO₄ solution</em> (the number of FeSO₄ moles is equal to the number of Fe⁺² moles):

  • moles = molarity * volume
  • 187 mL * 0.692 M = 129.404 mmol Fe⁺²

Then we convert Fe⁺² moles to KOH moles, using the stoichiometric ratios:

  • 129.404 mmol Fe⁺² * \frac{2mmolKOH}{1mmolFeSO_4} = 258.808 mmol KOH

Finally we<u> calculate the required volume of KOH solution</u>, using <em>the given concentration and the calculated moles</em>:

  • volume = moles / molarity
  • 258.808 mmol KOH / 0.440 M = 588.2 mL
6 0
2 years ago
Other questions:
  • How do you write 0.714 in scientific notation
    5·2 answers
  • When the above equation is balanced the coefficients in order are
    11·1 answer
  • What is the heat required to vaporize 650 grams of a liquid with a heat of vaporization of 723 joules/grams?
    14·1 answer
  • Ethanol boils at 78.4 °C with \DeltaΔHvap = 38.6 kJ/mol. A 0.200-mol sample of ethanol is heated from some colder temperature up
    11·1 answer
  • i really need the answer please i will give 30 points to the person that answers it i swear to god i put my hand on the bible Pa
    11·2 answers
  • 3 sources of background radiation and one source of radiation that is not condisderd background radiation
    9·1 answer
  • The isotope Np-238 has a half life of 2.0 days if 96 grams of it were present on Monday how much will remain six days later
    7·1 answer
  • Ron weasley isn't the best experimentalist. after an experiment he ends up with only 3.10 g of product. however, the same reacti
    12·1 answer
  • How many molecules of water can be produced from 46.72 liters of C8H18? 2\:C_8H_{18}\:+\:25\:O_2\:\:\Longrightarrow\:\:16\:CO_2\
    11·1 answer
  • What does a virus inject into a cell?
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!