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
svet-max [94.6K]
3 years ago
11

What is the molality of an aqueous kbr solution with a mole fraction of kbr, x, equal to 0.245?

Chemistry
1 answer:
kompoz [17]3 years ago
4 0
Molality is used to express concentration and it is:
molality = moles of solvent / kilogram solution

Now, lets assume there is one mole of solution. Then, there will be 0.245 moles of KBr and 0.755 moles of water. We multiply these molar fractions with the substances' molar masses to find the weight of one mole of solution.

Weight of one mole of solution = 0.245 * 119 + 0.755 * 18
Weight = 42.74 grams

Converting this weight to kilograms, this is 0.043 kg. We now multiply the moles of KBr by the kilograms of solution to find the molality:

molality = 0.245 / 0.043

The molality of the solution is 5.70 moles per kg
You might be interested in
For water at 30C and 1 atm: a= 3.04x10^-4 k^-1 , k =4.52x10^-5 atm ^-1 = 4.46 x10^-10 m^2/N, cpm= 75.3j/9molk), Vm =18.1cm^3/mol
Lapatulllka [165]

Answer:

C_{vm} of water at 30C and 1 atm is 256.834 J/mol·K.

Explanation:

To solve the question, we note the Maxwell relation such as

C_{pm}-C_{vm}=\frac{9T\alpha ^2 V }{K}

Where:

C_{pm} = Specific heat of gas at constant pressure = 75.3 J/mol·K

C_{vm} = Specific heat of gas at constant volume = Required

T = Temperature = 30 °C = 303.15 K

α = Linear expansion coefficient = 3.04 × 10⁻⁴ K⁻¹

K = Volume comprehensibility = 4.52 × 10⁻⁵ atm⁻¹

Therefore,

75.3 - C_v = \frac{9\times 303.15 \times (3.04 \times 10^{-1} 1.81  \times 10^{-5}  }{4.52 \times 10^{-5} }

C_{vm}  = \frac{9\times 303.15 \times (3.04 \times 10^{-1} 1.81  \times 10^{-5}  }{4.52 \times 10^{-5} } - 75.3 = 256.834 J/mol·K.

8 0
3 years ago
Based on the scientific sources you found, did you think one person’s points were more scientifically valid than the other’s
DanielleElmas [232]
What is research? Depending on who you ask, you will likely get very different answers to this seemingly innocuous question. Some people will say that they routinely research different online websites to find the best place to buy goods or services they want. Television news channels supposedly conduct research in the form of viewer polls on topics of public interest such as forthcoming elections or government-funded projects. Undergraduate students research the Internet to find the information they need to complete assigned projects or term papers. Graduate students working on research projects for a professor may see research as collecting or analyzing data related to their project. Businesses and consultants research different potential solutions to remedy organizational problems such as a supply chain bottleneck or to identify customer purchase patterns. However, none of the above can be considered “scientific research” unless: (1) it contributes to a body of science, and (2) it follows the scientific method. This chapter will examine what these terms mean
6 0
3 years ago
Read 2 more answers
If you need to measure the volume of liquid in a bottle of eyedrops, what unit would be the most practical?
nexus9112 [7]
The most practical would be milliliters
4 0
3 years ago
Read 2 more answers
What converts electric energy to radiant energy and thermal energy?
riadik2000 [5.3K]

Answer:

Many things, but i think a toaster...

Explanation:

8 0
3 years ago
Krupton (Kr) is a <br><br>A. Gas<br>B. Metal<br>C. Non of these<br>D. Metalloid​
Katarina [22]
B is gas


The chemical element krypton is classed as a noble gas and a nonmetal.







Love you
3 0
3 years ago
Other questions:
  • 2. List elements that need 3 electrons to have a stable outer shell.
    5·1 answer
  • Which of these molecules has the same number of shared electron pairs as unshared electron pairs? (a) hcl, (b) h2s, (c) pf3, (d)
    14·2 answers
  • How much 0.02 m kmno4 solution should be needed if the solutions tested have a composition of 3% h2o2 by mass?
    9·1 answer
  • When will a salt become less soluble in water?
    12·2 answers
  • a student is studying the ways different elements are similar to one another diagrams of atoms from four different elements are
    7·1 answer
  • a. Choose the best response for the following. The ionization energy for the chlorine atom is equal in magnitude to the electron
    7·1 answer
  • How many molecules are in
    14·1 answer
  • What is an energy conserved system ?
    12·1 answer
  • Determine the mass in grams of each element.
    12·1 answer
  • How many grams are there in 11.8 moles of sodium hydroxide
    11·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!