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
nevsk [136]
3 years ago
15

What should be the temperature of the solvent before adding it to the sample to be recrystallized?

Chemistry
1 answer:
Serhud [2]3 years ago
3 0

Answer:

Near the boiling point of the solvent

Explanation:

The process of recrystallization is hinged on the fact that the amount of solute that can be dissolved by a solvent increases with temperature. The process involves creation of a solution by dissolving a solute in a solvent at or near its boiling point.  At the boiling point of the solvent, the solute has a greater solubility in the solvent; not much volume of  the hot solvent is required to dissolve the solute.

Before the solution is later cooled, you can now filter out insoluble impurities from the hot solvent. The quantity of the original solute drops appreciably because impurities have been removed. At this lower temperature, the solution becomes saturated and the solute can no longer be held in solution hence it forms pure crystals of solute, which can be recovered.

Recrystallization must be carried out using the proper solvent. The solute must be relatively insoluble in the solvent at room temperature but more soluble in the solvent at elevated temperature.

You might be interested in
Alexandra decides to climb Mt. Krumpett, which is 5000 m high. She determines that this will require a total of 1350 kcal of ene
Kisachek [45]
Alexandra requires a total energy of 1350 kcal for the climb
by eating proteins, fats and carbohydrates the amount of calories per gram contributed varies.
Proteins and carbohydrates - 4 calories per gram 
fats - 9 calories and gram
This means that by eating the same mass of fats and proteins/ carbohydrats the calories gained from fats is higher.
each bar contains;
<span>50 g of carbohydrates - 4 calories/g x 50 g = 200 calories
10 g of fat - 9 calories/g x 10 g = 90 calories 
40 g of protein - 4 calories/g x 40 g = 160 calories 
total amount of calories from 1 bar = 200 + 90 + 160 = 450 calories 
energy required = 1 350 000 calories 
bars required = 1 350 000/450 = 3000
alexandra should consume 3000 bars </span>
8 0
3 years ago
What is the chemical formula for decomposition?
shutvik [7]

Answer: AB A + B

Explanation:

6 0
3 years ago
What is the mass of 5.119 102 molecules of copper sulfate<br> (CuSO4)?
Amiraneli [1.4K]

Answer:

Mass = 135.66 ×10⁻²¹ g

Explanation:

Given data:

Number of molecules of CuSO₄= 5.119×10²

Mass of CuSO₄= ?

Solution:

The given problem will solve by using Avogadro number.

1 mole contain 6.022×10²³ molecules

5.119×10² molecules ×1 mol / 6.022×10²³ molecules

0.85×10⁻²¹ mol

Mass in grams:

Mass = number of moles × molar mass

Mass = 0.85×10⁻²¹ mol × 159.6 g/mol

Mass = 135.66 ×10⁻²¹ g

7 0
3 years ago
If 30.943 g of a liquid occupy a space of 35.0 ml. What is the density of the liquid in g/cm3?
timofeeve [1]
Mass / volume = density
30.943g / 35ml = 0.88408571g/ml 

7 0
3 years ago
Read 2 more answers
What is the molar mass of nitrogen?
sukhopar [10]
The molar mass of nitrogen is 14.0067amu or just 14amu.
4 0
3 years ago
Other questions:
  • A sample of 2.0 moles of a metal reacts completely with excess oxygen to form 62.0 g of M2O. What element is represented by the
    10·1 answer
  • What is the difference between a solute and a solvent?
    5·1 answer
  • When the liquid state and the gaseous state of a substance are in equilibrium, the rate of evaporation is
    10·1 answer
  • Consider the molar solubility of SrCO3 in 0.10 M Sr(NO3)2 versus in pure water. Ksp SrCO3 = 5.4 x 10-10 Which statement is true?
    11·1 answer
  • A proposed mechanism for the reaction of NO2 and CO is
    5·1 answer
  • Hello,
    10·2 answers
  • Which of these is true of sound waves?
    5·1 answer
  • 3.<br> КОН<br> +<br> Н3РО4<br> 1<br> K3PO4<br> +<br> Н2O
    12·1 answer
  • Your weight changes if you travel to the moon because _____.
    6·2 answers
  • What is not a mass of 1 mole of a substance?
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!