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
Gre4nikov [31]
2 years ago
11

1. The Rast method for determining molar masses uses camphor as the solvent. Camphor melts at 178.4 °C, and its large Kf (37.7 K

kg mol-1) makes it especially useful for accurate work. A sample of an unknown substance that has a mass of 0.664 g reduces the freezing point of 25.0 g of camphor to 173.6 °C.
What is the molar mass of the unknown compound?
Chemistry
1 answer:
sergejj [24]2 years ago
4 0
The melting point of camphor is 178.4°C which is also the freezing point.
After the unknown substance is added, the freezing point is reduced to 173.6°C.
The freezing point depression is
178.4°C - 173.6°C = 4.8°C
The molar mass of the substance can be found using the equation
Kf m = 4.8
37.7 (0.664 / MW) = 4.8
MW = 5.22 g/mol
You might be interested in
The speed of sound in air is four times as its speed in steel true or false?​
alexgriva [62]

Answer:

.....false

Explanation:

the particles in the air are packed apart whereas the particles in steel are closely packed and sound travel faster in solids than in gasses..

4 0
3 years ago
Read 2 more answers
The mass of ethylene glycol (molar mass 62.1 g / mol), the main component of the antifreeze, must be added to 10.0 L of water to
ser-zykov [4K]
<h2> refer the attachment</h2>

<h2>If it is correct so mark as brainlest answer!</h2>

7 0
1 year ago
Balance each of the following examples of heterogeneous equilibria and write each Kc expression. Then calculate the value of Kc
wolverine [178]

Answer:

(1) 2Al(s) + 2NaOH(aq) + 6H2O(l) ↔2Na[Al(OH)4](aq) + 3H2(g)

∴ Kc = ( PH2³ * [Na[Al(OH)4]² ) / [NaOH]² = 11

(2) H2O(l) + SO3(g) ↔ H2SO4(aq)

∴ Kc = [ H2SO4 ] / PSO3 = 0.0123

(3) 2P4(s) + 6O2(g) ↔ 2P4O6(s)

∴ Kc = Kc = 1 / PO2∧6

Explanation:

(1) 2Al(s) + 2NaOH(aq) + 6H2O(l) ↔ 2Na[Al(OH)4](aq) + 3H2(g)

∴ O /  Al: 0 → +2 ≡ 2e-

         Na: +1 → +2

∴ R /  H: +1 → 0

     2 - Al - 2

     2 - Na - 1

     8 - O - 8

     14 - H - 14

⇒ Kc = ( PH2³ * [Na[Al(OH)4]² ) / [NaOH]² = 11

(2) H2O(l) + SO3(g) ↔ H2SO4(aq)

           1 - S - 1

           4 - O - 4

           2 - H - 2

⇒ Kc = [ H2SO4 ] / PSO3 = 0.0123

(3) 2P4(s) + 6O2(g) ↔ 2P4O6(s)

       8 - P - 8

       12 - O - 12

⇒ Kc = 1 / PO2∧6

6 0
3 years ago
A compound is made up of iron and oxygen, only. The ratio of iron ions to oxide ions is 2:3 in this compound. The IUPAC name for
never [62]

Answer: The correct option is 3.

Explanation: We are given a compound which is made up of iron and oxygen only. The ratio of the two are given as:

\frac{\text{iron ions}}{\text{oxide ions}}=\frac{2}{3}

This means that, number of iron ions are 2

Number of oxide ions are 3

From the above information, the formula becomes : Fe_2O_3

The valency of iron = 3

Valency of oxide = 2

This compound is named as iron (III) oxide.

Hence, the correct option is 3

6 0
3 years ago
Read 2 more answers
When we react a weak acid with a strong base of equal amounts and concentration, the component of the reaction that will have th
Svetllana [295]

Answer and explanation:

Initially, the pH of the solution will be determined by the dissociation of the weak acid.

Usually, this kind of solution consists of a mixture of weak acid that has not yet reacted and the salt that will be formed by the reaction of the weak acid with a strong base that has been added.

After the dissociation process, the pH will be more affected due to the excess of base in the solution.

5 0
3 years ago
Other questions:
  • Describe why an element's physical properties are different from its chemical properties. Include in your answer an example of o
    9·1 answer
  • True or false: A mechanical wave starts with a disturbance in matter
    5·1 answer
  • When reacting 45g of magnesium with oxygen, 50.0g of magnesium oxide is produced. Calculate the theoretical yield and percent yi
    5·1 answer
  • Caitlin told Teddy that she heard that the largest diamond was found yesterday in Africa. What would be the best source of resea
    8·2 answers
  • A train traveled at an average speed of 80 mph for
    5·1 answer
  • According to the principle of the conservation of mass the mass of the sodium sulfate was the following PLS HELP I NEED TO TURN
    8·1 answer
  • Question 10 of 10
    11·1 answer
  • Electrons in Atoms
    9·2 answers
  • Another one please help
    14·1 answer
  • The distances from large bodies of water will affect the average rainfall of an area. (Example: Florida has more rain than Nevad
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!