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
alina1380 [7]
2 years ago
10

When 551. mg of a certain molecular compound X are dissolved in 100 g of benzonitrile (CH,CN), the freezing point of the solutio

n is measured to be 13.4 °C. Calculate the molar mass of X.
Chemistry
1 answer:
arsen [322]2 years ago
5 0

Answer:

1.12g/mol

Explanation:

The freezing point depression of a solvent for the addition of a solute follows the equation:

ΔT = Kf*m*i

<em>Where ΔT is change in temperature (Benzonitrile freezing point: -12.82°C; Freezing point solution: 13.4°C)</em>

<em>ΔT = 13.4°C - (-12.82) = 26.22°C</em>

<em>m is molality of the solution</em>

<em>Kf is freezing point depression constant of benzonitrile (5.35°Ckgmol⁻¹)</em>

<em>And i is Van't Hoff factor (1 for all solutes in benzonitrile)</em>

Replacing:

26.22°C = 5.35°Ckgmol⁻¹*m*1

4.90mol/kg = molality of the compound X

As the mass of the solvent is 100g = 0.100kg:

4.9mol/kg * 0.100kg = 0.490moles

There are 0.490 moles of X in 551mg = 0.551g, the molar mass (Ratio of grams and moles) is:

0.551g / 0.490mol

= 1.12g/mol

<em>This result has no sense but is the result by using the freezing point of the solution = 13.4°C. Has more sense a value of -13.4°C.</em>

You might be interested in
A car is driven for 3 hours. What else do you need to know to describe this car's speed?
s2008m [1.1K]

Answer: Distance the car has driven

Explanation:

The speed equation is speed=distance/time and since we already know time we need to know distance to solve for speed

4 0
2 years ago
The number of electrons in the valence shell determine what types of bonds an atom can form.
Nataly_w [17]
This statement is right !
8 0
2 years ago
Which type of bond is found between atoms and solid cobalt?
zheka24 [161]
Cobalt is a metal thus the atoms are bonded together in giant atomic structures and metallic bonds. The atoms attract each other with very strong atomic forces this the resulting structure is giant atomic structures. This provides for the extra strong structure of cobalt.
3 0
2 years ago
Describe 3 methods to increase the rate of dissolution for sugar in a cup of tea
Xelga [282]
1. Stirring. This will agitate the sugar and encourage it to dissolve. Stirring creates friction and motion, which in turn will create heat that pulls the sugar particles apart as they are given energy. 

2. Applying heat. As mentioned in the previous method. The application of heat gives extra energy to the sugar molecules which encourages it to pull apart and dissolve. 

3. Increase the surface area. Where more sugar particles are fully submerged in the tea or being surrounded by the tea, the rate of dissolution will increase. 
8 0
3 years ago
What is the molar mass for Mg3(PO4)2?
Black_prince [1.1K]
The answer is 262.855g/mol
4 0
3 years ago
Other questions:
  • Why is it better to give the actual speed of an object rather than to simply say it moved fast or it moved slowly
    7·1 answer
  • 2KClO3 2KCl + 3O2
    12·1 answer
  • A compoundwhose water solution conducts electricity and turns phenolphthalein pink is?
    10·1 answer
  • Which of these statements best explains why the soil around a volcanic region is fertile?
    9·2 answers
  • 38.2mm converted into cm
    13·1 answer
  • Given the system at equilibrium:
    6·1 answer
  • Please help this is very important​
    14·1 answer
  • Say something hot ;)
    5·2 answers
  • The temperature of a 100.0 g sample of water is raised from 30degrees celsius to 100.0 degrees celsius. How much energy is requi
    15·1 answer
  • 1. Describe how SHAPE can change during a collision. Be specific with your evidence and add detail to your answer.
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!