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
xxTIMURxx [149]
3 years ago
7

Methyl benzoate was prepared by the reaction of benzoic acid with methanol in the presence of a mineral acid. The ester product

was extracted into dichloromethane and then shaken with saturated sodium chloride solution. What is the purpose of the sodium chloride? To cause the water to be immiscible with the methylene chloride. To raise the density of the aqueous layer so that it will be the bottom layer. To lower the boiling point of the water. To decrease the solubility of the organic product in water.
Chemistry
1 answer:
Alex777 [14]3 years ago
4 0

Answer:

To decrease the solubility of the organic product in water.

Explanation:

Methyl benzoate is prepared via <em>Fischer esterification </em>reaction between benzoic acid and methanol in the presence of a mineral acid. The following steps are involved:

  1. Benzoic acid is dissolved in methanol in a round bottom flask.
  2. Concentrated sulphuric acid is added and heated under reflux on a steam bath
  3. Reaction is poured into ice, reaction flask is rinsed with dichloromethane. Layers collected in a test tube.
  4. Dichloromethane layer is then washed with first sodium carbonate solution(this is done inorder to neutralize and remove the residual benzoic acid) and then with sodium chloride solution(to decrease the solubility of the organic product in water).
  5. Then Dichloromethane solution is dried over magnesium sulphate.
  6. Dichloromethane is removed via distillation on a steam bath.
  7. Collect distillate in a vial on a heating mantle.
You might be interested in
5. Calculate the number of grams in a sample<br> of 1.025 moles of MgCO,.
snow_lady [41]

Answer:

41/40

Explanation:

3 0
3 years ago
A gas mixture contains 0.800 mol of N2, 0.200 mol of H2, and 0.150 mol of CH4. What is the mole fraction of H2 in the mixture?
Blababa [14]

Answer:

0.1739

Explanation:

0.800 mol of N2

0.200 mol of H2

0.150 mol of CH4

Total moles of the mixture = 0.8 + 0.2 + 0.150 = 1.150 mol

Mole fraction of H2 = Number of moles of H2 /  Total moles

Mole Fraction = 0.2 / 1.150 = 0.1739

4 0
3 years ago
Which is a process that causes an organism’s poorly suited characteristics to disappear?
rusak2 [61]
The answer to your question is c , Natural selection
4 0
3 years ago
consists of two or more different types of atoms bonded together. is a combination of different substances that can be separated
tresset_1 [31]

Answer:

1. A molecule

2. A mixture

3. Concentration

4. Chemical formula

5. Kinetic energy

Explanation:

1. A molecule consists of two or more different types of atoms bonded together.

For this question, it's important to understand that we cannot be too abstract and use terms, such as compound. The reason is simple: molecules consist of atoms, and while molecules produce compounds, the latter can also be ionic. Ionic compounds would contain ions in them rather than atoms. In ionic compounds, electrons are transferred from one atom to the other to form cations and anions.

Molecules, on the other hand, consist of atoms. In fact, those atoms shouldn't necessarily be different: for example, we may have an oxygen gas molecule which consists of two oxygen atoms.

2. A mixture is a combination of different substances that can be separated by physical means.

Usually, mixtures are in the same physical state, for example, we may have a mixture of an aqueous layer, such as water, and an organic layer, such as hexane. In order to separate them, we might use a separation funnel, as water is polar and hexane is non-polar, they will form two separate layers. Collecting the bottom layer in a separate flask from the funnel and then the remaining layer will help us separate them based on their difference in polarity.

3. Many variables in chemistry depend on the amount of water present. Water is a solvent. One of the typical examples is concentration. Concentration, or molarity, is a ratio between the moles of a solute and the volume of a solution. Changing the amount of water would change the concentration of a solute as a result.

E. g., if we evaporate water, our solvent, from a specific solution, the concentration of a solute will increase, as we'll have the same amount of a solute in moles for a lower volume of a solution. Similarly, if we dilute the solution (increase the volume of it by adding more water), the volume will increase and we'll have the same amount in moles of the solute for a greater amount of the solution, so the concentration will decrease.

4. A chemical formula has fixed definite proportions at all times. Regardless of what mass of a compound we have, according to the law of definite proportions, atoms always combine in a fixed ratio in compounds. For example, we know that we would always have two hydrogen atoms and one oxygen atom in a water molecule regardless of what mass of water we have.

Similarly, if we remember ionic compounds, if we take sodium chloride, NaCl, the ionic ratio between sodium and chloride ions is always 1 : 1 (one sodium cation combined with one chloride anion). This is fundamentally true and it's independent of any quantity.

5. Similarly, this is an open question. A typical answer to this would be kinetic energy. Kinetic energy only depends on temperature of a substance. Kinetic energy is the energy of movement: the greater it is, the greater the velocity of an object.

The greater the temperature, the higher the kinetic energy. This direct proportionality is seen from the equation E_k = \frac{3}{2} kT, where k is a constant and T is the absolute temperature. Notice that for higher T values, the kinetic energy term is higher.

Thinking about it from the other perspective, density, as another example, also depends on temperature. The greater the temperature, the greater the distances between the molecules, so the density decreases with an increase in temperature.

There are many more thermodynamic examples to look at as well!

8 0
3 years ago
Using the formula velocity = distance/time, how fast does sound travel in air at 20 degrees C given a distance of 500 m and 3.92
mixas84 [53]

Answer:

B : 127m/s

Explanation:

= 500 ÷ 3.92

= 127.5

5 0
3 years ago
Other questions:
  • The elements X and Y combine in different ratios to form four different types of compounds: XY, XY2, XY3, and XY4. Consider that
    15·1 answer
  • The molar mass of CO2 is 44.01 g/mol. Which is the mass of 3.21×1025 molecules of CO2
    7·1 answer
  • List the levels of the Mohs hardness scale – For EACH level, tell the characteristics found in minerals on that level and give 1
    13·1 answer
  • Why does the person keep moving even though the car stopped??
    9·1 answer
  • 30.00 grams of H3PO4
    5·1 answer
  • (this is 6th grade science so that’s the closet subject I could find) Do you know an adult who drinks coffee, tea, or soda pop?
    13·1 answer
  • Consider the ionization constants cyanic acid (HOCN) : Ka= 3.5×10−4; ammonia (NH3): Kb= 1.8×10−5. A solution
    14·1 answer
  • 1. Patient is admitted with neck injury which has resulted in a loss of function in their thyroid.
    15·1 answer
  • Describe a second degree burn ​
    12·1 answer
  • Which surface will produce the most friction for the fan cart?
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!