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
dexar [7]
3 years ago
6

In addition to the separation techniques used in this lab (magnetism, evaporation, and filtering), there are other commonly used

separation techniques. Some of these techniques are:
Distillation – this process is used to separate components that have significantly different boiling points. The solution is heated and the lower boiling point substance is vaporized first. The vapor can be collected and condensed and the component recovered as a pure liquid. If the temperature of the mixture is then raised, the next higher boiling component will come off and be collected. Eventually only non-volatile components will be left in the original solution.
Centrifugation – a centrifuge will separate mixtures based on their mass. The mixture is placed in a centrifuge tube which is then spun at a high speed. Heavier components will settle at the bottom of the tube while lighter components will be at the top. This is the technique used to separate red blood cells from blood plasma.
Sieving – this is similar to filtration, but the sample is passed through a screen which allows smaller particles to go through and retains the larger particles.
Paper chromatography – this is a technique that separates of mixture based on the individual substance’s tendency to travel across a paper surface. This technique is used frequently to separate different dyes.
Separatory Funnel – this is a glass container with a stopcock on the bottom. Two immiscible solutions are put in it. Since the compounds do not mix, they will separate into two layers, the heavier one will be on the bottom. The stopcock can then be opened and the heavier liquid will flow out and can be collected.
Consider the following separation problems. Decide which of the above techniques, including the ones you used in your lab, would be the best to use for separating the solutions. You may need to use more than one technique for a given sample. Then give a brief explanation as to how you would do the separation.
A. Water and Sugar
B. Mixture of Hexane (Boiling Point = 68.7oC) and Octone (Boiling Point = 125oC)
C. Solid I2 (non-polar solid) and NaCl
D. "Sharpie" permanent marking pen
E. Nickel shavings and copper pellets
Chemistry
1 answer:
DENIUS [597]3 years ago
4 0

Answer:

A. Water and Sugar  can be separated by evaporation and then crystallization

B. Mixture of Hexane and Octane can be separated by distillation

C. Solid Iodine, I₂ and NaCl  can be separated by filtration and then evaporation

D. "Sharpie" permanent marking pen  can be separated by  chromatography

E. Nickel shavings and copper pellets can be separated by magnetic separation

Explanation:

A. A mixture of water and sugar can be separated by employing two separation techniques, evaporation and crystallization. First the sugar solution  is heated to evaporate most of the water. When the solution becomes very saturated, it is allowed to cool and then the sugar molecules are obtained through crystallization induced by seeding or scratching the walls of the container.

B. A mixture of hexane (boiling point = 68 °C) and Octane (boiling point = 125 °C) can be separated by distillation due to their significant difference in boiling points.

The mixture is heated in a flask connected to a Liebig condenser. Hexane with the lower boiling point will distill over first and is collected. Afterwards, octane next distills over and is collected as well.

C. A mixture of solid iodine and NaCl can be seperated by first dissolving in water. Iodine being non- polar does not dissolve and is collected as a residue from filtration using a filter paper, while the NaCl solution is collected as the filtrate. The NaCl is recovered from solution by evaporating to dryness in an evaporating dish.

D. "Sharpie" permanent marking pen contains a mixture of dyes which can be separated by paper chromatography.

A drop of the marker ink is placed on a spot above the solvent level on the paper strip used for the separation. The paper strip is  held vertically inside a jar containing a solvent which serves as the mobile phase. The jar is covered and the different dyes move along the paper which serves as the stationary phase, and is thus separated. The paper strip is removed from the jar when the ascending front of the solvent is approaching the top of the paper. The paper is dried and the various dyes can be identified by comparing the distance each has traveled with those of standards.

E. A mixture of nickel shavings and copper pellets can be separated by magnetic separation.

A magnet is brought near the mixture and the nickel shavings being magnetic is attracted to the magnet leaving copper pellets behind since copper is not magnetic.

You might be interested in
Make a suggestion on how you will deal with the problem..
Trava [24]

Answer:

and the last name then select a City the solution if they are getting elimination method if I can tell u that is telling you about me to this email and delete this email and any attachments may contain confidential information and rupees hundred years ago the pair in the solution if I can tell you my story of my teacher not respond please ask me to this email and any attachments is intended only for the independence of Bangladesh and what is the correct answer is yes we have to come at your earliest convenience and what is the correct answer

7 0
3 years ago
Read 2 more answers
What is the value of the σ∗1s mo wave function at the nodal plane?
Leona [35]

Answer:

There is None

Explanation:

This is because it is a derived function dependent on other factors.

5 0
3 years ago
Read 2 more answers
What is the meaning of the word solubility
LekaFEV [45]
Amount of a substance (called the solute) that dissolves in a unit volume of a liquid substance (called the solvent) to form a saturated solution under specified conditions of temperature and pressure.Solubility is expressed usually as moles of solute per 100 grams of solvent.
3 0
3 years ago
Read 2 more answers
9. Sodium reacts with water to produce sodium hydroxide and hydrogen gas, as shown below.
saveliy_v [14]

Answer:

B

Explanation:

2Na + 2H2O2==NaOh + H2

184/23=x/18

x=(184×18)/23

x=144g

4 0
3 years ago
PLEASE HELP!!!!!!!
dsp73

Answer: 1. 2Al+3CuCl_2\rightarrow 2AlCl_3+3Cu

2. 3 moles of CuCl_2 : 2 moles of Al

3. 0.33 moles of CuCl_2 : 0.92 moles of Al

4. CuCl_2 is the limiting reagent and Al is the excess reagent.

5. Theoretical yield of AlCl_3 is 29.3 g

Explanation:

To calculate the moles :

\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}    

\text{Moles of} Al=\frac{25.0g}{27g/mol}=0.92moles

\text{Moles of} CuCl_2=\frac{45.0g}{134g/mol}=0.33moles

The balanced chemical equation is:

2Al+3CuCl_2\rightarrow 2AlCl_3+3Cu  

According to stoichiometry :

3 moles of CuCl_2 require = 2 moles of Al

Thus 0.33 moles of CuCl_2 will require=\frac{2}{3}\times 0.33=0.22moles  of Al

Thus CuCl_2 is the limiting reagent as it limits the formation of product and Al is the excess reagent.

As 3 moles of CuCl_2 give = 2 moles of AlCl_3

Thus 0.33 moles of CuCl_2 give =\frac{2}{3}\times 0.33=0.22moles  of AlCl_3

Theoretical yield of AlCl_3=moles\times {\text {Molar mass}}=0.22moles\times 133.34g/mol=29.3

Thus 29.3 g of aluminium chloride is formed.

5 0
2 years ago
Other questions:
  • What type of shoes should a student wear while working with chemical and with glassware
    8·2 answers
  • Although there are different ways to approach a scientific investigation, all scientific investigations begin with some sort of
    14·2 answers
  • A baby weighs 3.91 kg and measures 51.4 cm. Convert the baby's weight
    8·1 answer
  • When mountains are young, like the Rocky Mountains, they are very tall, with sharp jagged shapes. When mountains are old, they
    13·1 answer
  • Do you think that scientists should continue to try to create super-heavy elements and expand the periodic table? Explain why or
    11·2 answers
  • 1.
    8·1 answer
  • Calculate the molecular mass of iron (Ill) oxide (Fe,O3)
    11·1 answer
  • A physical change is when the atoms combine to create a new product.
    8·1 answer
  • Sodium azide is stable at room temperature but decomposes quickly at temperatures above 300°C. It is moderately inexpensive to m
    12·1 answer
  • Cual es la formula estructural condensada del octano??
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!