After the reaction mixture is added to the top of the silica gel column, the instructions state: "Open the stopcock and drain the column until the meniscus is just above the top layer of the material. Add another 0.5 mL of solvent and repeat the process toensure that all of the desired products are adsorbed onto the silica gel. This process ensures that none of the desired products are dissolved in solution above the column."Why is this procedure important? How would the TLC plates look different than your prediction in Q1 if a student skipped this step?

Answers

Answer 1

Answer:

Kindly check the explanation section.

Explanation:

Without mincing words let's dive straight into the solution to the question.

The instructions given in the question above is very important as it concerns the total adsorption of the product on the silica gel. The instruction is made so that adsorption of the product is on the silica gel so as to avoid the distortion in polarity of the compound.

Part B.

If the student avoid the step, there would be problem of which the compound which is in mixture will be running out of the column. Also, the compounds won't be made pure.

In summary, for the first part adsorption is done on the silica gel thus, the instructions is to be followed.

For the second part, if the step is not avoided then the Compounds will be made pure if the step


Related Questions

Calculate the volume in mL of 0.100 of CaCl2 needed to produce 1.00 g of CaCO3. there is an excess of Na2CO3

Answers

Answer:

100. mL

Explanation:

The computation of the volume in mL is shown below:

The balance equation of the double displacement reaction is

[tex]CaCl_{2} + Na_{2}CO_{3} \rightarrow 2 NaCl + CaCO_{3}[/tex]

Now determine the moles that corresponding to 1.00 g of CaCO₃

As,

The molar mass of CaCO₃ is 100.09 g/mol.

So,

= 1.00 g × 1 mol/100.09 g

= 0.0100 mol

Now

the moles of CaCl₂ needed to generate 0.0100 moles of CaCO₃

As we know that

The molar ratio of CaCl₂ to CaCO₃ is 1:1.

So, The moles of CaCl₂ needed is

=  1 ÷ 1 × 0.0100 mol

= 0.0100 mol.

Now volume of 0.100 M CaCl₂ that contains 0.0100 mol is  

= 0.0100 mol × 1 L/0.100 mol × 1000 mL/1 L

= 100. mL

Look at sample problem 19.10 in the 8th ed Silberberg book. Write the Ksp expression. Find the concentrations of the ions you need (in this case Ca2 and F-). Put those concentrations into the Ksp expression to calculate Q. Compare Q to K A common laboratory method for preparing a precipitate is to mix solutions containing the component ions. Does a precipitate form when 10. ml of 0.0010 M Ca(NO3)2 is mixed with 10. ml of 0.00010 M NaF

Answers

Answer:

Explanation:

From the information given:

[tex]CaF_2 \to Ca^{2+} + 2F^-[/tex]

[tex]Ksp = 3.2 \times 10^{-11}[/tex]

no of moles of [tex]Ca^{2+}[/tex] = 0.01 L × 0.0010 mol/L

no of moles of [tex]Ca^{2+}[/tex] = [tex]1 \times 10^{-5} \ mol[/tex]

no of moles of [tex]F^-[/tex] = 0.01 L × 0.00010 mol/L

no of moles of [tex]F^-[/tex] = [tex]1 \times 10^{-6}\ mol[/tex]

Total volume = 0.02 L

[tex][Ca^{2+}}] = \dfrac{1\times10^{-5} \ mol}{0.02 \ L} \\ \\ \\ \[[Ca^{2+}}] = 0.0005 \ mol/L[/tex]

[tex][F^{-}] = \dfrac{(1\times 10^{-6} \ mol)}{0.02 \ L}[/tex]

[tex][F^{-}] = 5 \times 10^{-5} \ mol/L[/tex]

[tex]Q = [Ca^{2+}][F^-]^2 \\ \\ Q = 0.0005 \times (5\times 10^{-5})^2 \\ \\ Q = 1.25 \times 10^{-12}[/tex]

Since Q<ksp, then there will no be any precipitation of CaF2

What is the functional groups of CH3CH2CH(OH)CH2C(CH3)2Br?​

Answers

Answer:

What is the functional groups of CH3CH2CH(OH)CH2C(CH3)2Br?

Which factors play a role in creating ocean waves?

Choose all answers that are correct.


wind duration

wind speed

wind change

wind elevation

wind direction

wind fetch

Answers

Answer:

1. Wind speed

2. Wind change

3. Wind elevation

4. Wind direction

Answer:

For k12 its::

Explanation:

wind direction

wind speed

wind fetch

wind duration

Yw guys! ^^

An aqueous solution of nitric acid is standardized by titration with a 0.174 M solution of barium hydroxide. If 13.9 mL of base are required to neutralize 28.7 mL of the acid, what is the molarity of the nitric acid solution?

Answers

Answer:

Explanation:

2HNO₃ + Ba( OH)₂ = Ba( NO₃ )₂ + 2H₂O .

2 mole      1 mole

13.9 mL of .174M barium hydroxide contains .0139 x .174 moles

= 2.42 x 10⁻³ moles .

1 mole of barium hydroxide reacts with 2 moles of nitric acid

2.42 x 10⁻³ moles of barium hydroxide will react with 2 x 2.42 x 10⁻³ moles of nitric acid

= 4.84 x 10⁻³ moles

4.84 x 10⁻³ moles of nitric acid is contained in 28.7 mL

molarity of nitric acid = 4.84 x 10⁻³ / 28.7 x 10⁻³

= .169 M .

Which word best describes the relationship between polyps and algae
exoskeletal
Bleached
Photosynthetic
Symbiotic

Answers

Answer:

symbiotic

Explanation:

There like a close friendship

Explain how the Octet Rule would say that the elements of potassium and chlorine would react.

Answers

Answer:

The octet rule is only applicable to the main group elements. The molecules of the halogens, oxygen, nitrogen, and carbon are known to obey the octet rule. In general, the elements that obey this rule include the s-block elements and the p-block elements (except hydrogen, helium, and lithium).

Explanation:

I hope this helps and pls mark me brainliest :)

Fred is about to order a stack of four pancakes with butter and syrup, but he wonders how much he would need to exercise to burn off the Calories from it. He pulls out his cell phone and finds the nutritional information for the stack of pancakes. He notes that a serving has 181g of carbohydrates, 27g of fat, and 16g of protein. Now, he has to convert these values into Calories.

Running at a pace of 8 minutes per mile burns 14 Calories/minute. How many minutes would he have to run at an 8 minutes per mile pace to bum off the Calories from the stack of pancakes?

Answers

Answer:

The correct answer is - 73.64 minutes.

Explanation:

We know that each gram of protein and carbohydrate produces 4 calories of energy whereas fat produces 9 cal energy per gram.

So, the Calories from carbohydrates

= 181 ×4

= 724 Cal

and, 27 g fat produces = 27 × 9 = 243 Cal

and, 16 g protien = 16 × 4 = 64 Cal

so the total energy will be - 243+ 724+ 64 = 1031 Cal

Thus, the time Fred need to run = 1031/14 =73.64 min

If the mercury in a manometer raises 30.0 millimeters due to a change in pressure, what is the corresponding change in pressure in atm?

Answers

Answer:

0.03947 atm

Explanation:

The relationship between mmHg and atm is given as;

1 atm = 760 mmHg

x atm = 30 mmHg

Upon solving for x;

x * 760 = 30 * 1

x = 30 / 760 = 0.03947 atm

50 POINTS
Which of the following correctly describes a compound?

A. The atoms are bonded together, and the compound has different physical and chemical properties than the individual elements.
B. The atoms have no set ratio for how the atoms can combine, and they are not chemically bonded together.
C. The atoms can only combine in fixed ratios, and they retain their individual chemical and physical properties.
D. The atoms retain their individual chemical properties, and they can only be separated from each other by a chemical change.

Answers

Answer: A chemical compound can be described as substance composed of atoms from more than one element held together by chemical bonds in a fixed stoichiometric proportion. A compound has different physical and chemical properties from its constituent elements.

For example : compound water is made up of H and O bonded together and it has different properties from O and H.

Thus, among the given options, the one coreectly describing a compound is

a) The atoms are bonded together, and the compound has different physical and chemical properties than the individual elements.

Write the word equation for
the reaction between sodium
hydrogen carbonate and
sulfuric acid.

Answers

Answer:

NaHCo3+Na2So4---Nna2So4+H2O+CO2

Answer:

sodium two sulphate+Carbondioxed gas +water

What are bacteria? Are they good or bad?

Answers

Answer:

Bacteria are a type of biological cell. They constitute a large domain of prokaryotic microorganisms

some are good some are bad

Explanation:

Name the compound AgF

Answers

Answer: Silver (I) fluoride molecule · AgF

Classification: Inorganic compound (Could be salt)

Ionic compound (Silver is a metal)

Valence of F (F must form an octet): 7

Valence of Ag: 11

Total valence electrons: 18

Molar mass: 126.87 g/mol

 

Explanation:

This is the chemical formula for Chormium (III) nitrate Cr(NO3)3Calculate the mass percent of nitrogen in chromium(III) nitrate.

Answers

Answer:

The percent composition for nitrogen in chromium(III) nitrate is 6%.

Explanation:

The mass percent of nitrogen in chromium(III) nitrate is 17.655%.

Calculation,

Molar mass of one oxygen = 16 g

molar mass of nine oxygen = 9 × 16 g = 144 g

molar mass of one nitrogen atom = 14 g

molar mass of three nitrogen atom = 3 × 14 g = 42 g

molar mass of one chromium atom = 51.99 g

molar mass of chromium (III) nitrate molecule = 144 g + 42 g + 51.99 g = 237.99 g

Mass percent of nitrogen = mass of three nitrogen atom× 100 /mass of chromium(III)nitrate

Mass percent of nitrogen = 42 g/237.99 g × 100 = 17.655%

What is mass percentage?

The percentage of the mass of the element or solute divided by the mass of the compound or solute is called mass percentage

learn about mass percentage,

https://brainly.com/question/16885872

#SPJ2

The following table lists molecular weight data for a polypropylene material. Molecular Weight Range (g/mol) xi wi
8,000 - 16,000 0.07 0.03 16,000 - 24,000 0.15 0.09 24,000 - 32,000 0.26 0.21 32,000 - 40,000 0.27 0.27 40,000 - 48,000 0.18 0.28 48,000 - 56,000 0.07 0.12
Click here to access Table 14.3. Atomic weights for several elements are included in the following table: Carbon 12.01 g/mol Chlorine 35.45 g/mol Fluorine 19.00 g/mol Hydrogen 1.008 g/mol Oxygen 16.00 g/mol Nitrogen 14.01 g/mol Compute the following:
(a) the number-average molecular weight, Enter your answer for part (a) in accordance to the question statement g/mol
(b) the weight-average molecular weight, Enter your answer for part (b) in accordance to the question statement g/mol
(c) the degree of polymerization.

Answers

Answer:

a) the number-average molecular weight is 32,400 g/mol

b) the weight-average molecular weight is 36,320 g/mol

c) the degree of polymerization is 770

Explanation:

Given the data in the question;

Molecular                  Mean        Number      Weight      Number        Weight

weight                                                                             average         average

(g/mol)                    Mi(g/mol)         xi                wi          xiMi                  wiMi

8,000-16,000            12,000        0.07           0.03         840                360

16,000-24,000          20,000       0.15           0.09         3000              1800

24,000-32,000         28,000       0.26           0.21          7280              5880

32,000-40,000         36,000       0.27           0.27         9720               9720

40,000-48,000         44,000       0.18            0.28         7920              12320

48,000-56,000         52,000       0.07           0.12          3640              6240

∑                                                                                Mn=32,400     Mw=36,320

so;

a)  the number-average molecular weight

Mn = ∑Mixi

so from the table above; summation of Row Mixi

Mn = ∑Mixi = 32,400

Therefore, the number-average molecular weight is 32,400 g/mol

b) the weight-average molecular weight

Mw = ∑Miwi

so from the table above; summation of Row Miwi

Mw = ∑Miwi = 36,320

Therefore, the weight-average molecular weight is 36,320 g/mol

c) the degree of polymerization

the degree of polymerization of polypropylene can be determined using number-average molecular and repeat unit molecular weight.

now, for polypropylene { CH₂ = CH - CH₃ }

the repeat unit consist of 3 carbon atoms and 6 hydrogen atoms

given that;

Atomic weight of Carbon mC = 12.01 g/mol and

Atomic weight of  Hydrogen mH = 1.008 g/mol

now we find the repeat unit molecular weight of polypropylene

m = nCmC + nHmH

where n is the number of repeat of atoms

so we substitute

m = ( 3 × 12.01) + ( 6 × 1.008)

m = 36.03 + 6.048

m = 42.078 g/mol

now we calculate the degree of polymerization;

DP = Mn / m

so we substitute

DP = 32,400 / 42.078

DP = 769.9985 ≈ 770

Therefore,  the degree of polymerization is 770

Steam is collected and observed to condense into liquid water. Which of the following would you expect to observe if a thermometer recorded the temperature of the substance?

SELECT AN ANSWER

The temperature would decrease.


The temperature would remain the same.


It would depend on the amount of steam.


The temperature would increase.

Answers

the water will be increased

Calculate the mass, in grams, of 912 atoms of iron, Fe (1 mol of Fe
has a mass of 55.85 g).

Answers

Answer:

8.45 × 10⁻²⁰ g

Explanation:

Step 1: Given data

Number of atoms of Fe (N): 912 atomsMolar mass of Fe (M): 55.85 g/mol

Step 2: Calculate the mass, in grams, of 1 atom of Fe

We will use Avogadro's number: there are 6.02 × 10²³ atoms of Fe in 1 mole of Fe.

55.85 g/mol × 1 mol/6.02 × 10²³ atom = 9.27 × 10⁻²³ g/atom

Step 3: Calculate the mass corresponding to 912 atoms

9.27 × 10⁻²³ g/atom × 912 atom = 8.45 × 10⁻²⁰ g

Kinematics equations are used only by physicists and people who work in
space.
A. True
B. False

Answers

Answer:

FALSE

Explanation:

false. kinematics equations are used for many purposes.it is used to drive equations and to find the motion of an object. but it is used more in physics rather than maths.

answer is correct. :)

How can we solve food insecurity while reducing food waste?
o inventory food supplies to avoid overbuying
O donate unused food to food banks
O purchase only as much food as you need
O don't throw scraps in the landfill

Answers

Answer:

donate unused food to food banks

Explanation:

Becuse food banks processes food to make very fine particles which is mixed with soil and can be given to the plants

WILL MARK BRAINLIST
If a car travels 60 miles for two hours, what is the average speed?
15 mi/hr
30 mi/hr
45 mi/hr
60 mi/hr

Answers

Answer:

The average speed must be 30mph so this means the car traveled for 2hrs 60/30

Titanium(IV) chloride decomposes to form titanium and chlorine, like this:

TiCl4(l) → Ti(s)+ 2Cl2(g)

At a certain temperature, a chemist finds that a reaction vessel containing a mixture of titanium(IV) chloride, titanium, and chlorine at equilibrium has the following composition:

Compound Amount
TiCl4 4.18g
Ti 1.32g
Cl2 1.08g

Required:
Calculate the value of the equilibrium constant for this reaction.

Answers

The full question is shown in the image attached to this answer

Answer:

6.2 * 10^-3

Explanation:

The reaction at equilibrium is as follows;

TiCl4(l) → Ti(s)+ 2Cl2(g)

We have to obtain the concentration of chlorine gas as follows;

[Cl2] = 1.08/70.91 g/mol × 5.2 L

[Cl2] = 0.079 M

Kc = [Cl2]^2

Kc = [ 0.079]^2

Kc = 6.2 * 10^-3

Which of the following are true about an atom? Choose all that apply.

Answers

Answer:

Explanation:

Atoms are the building blocks of matter.

They are the smallest particles of an element that still have the element's properties.

All atoms are very small, but atoms of different elements vary in size.

Three main types of particles that make up all atoms are protons, neutrons, and electrons.

Question 6 of 25
When nonionizing radiation is absorbed by matter, it usually becomes which
type of energy?
A. Thermal
B. Mechanical
C. Electromagnetic
O D. Chemical

Answers

Answer:

thermal

Explanation:

a p e x

Explain why NO is more soluble in water than either N2 or O2. Fill in the following blanks.

a. Compared to nitrogen, the ____________of ethylene makes it more soluble in water.
b. The high solubility of sulfur dioxide can be explained by its ______________
c. Nitric oxide is more soluble than nitrogen and oxygen because of its ______________
d. Compared to oxygen, nitrogen's _____________ makes it more difficult for water molecules to surround the nitrogen molecules.

1. Polarity
2. Ability to react with water
3. Shorter bond length
4. Larger molecular size

Answers

Answer:

a. Larger molecular size

b. Ability to react with water

c. Polarity

d. Shorter bond length

Explanation:

Ethene is a larger molecule than oxygen and nitrogen hence it is more soluble than the both other gases .

SO2 dissolves readily in water to yield an acid solution. It is an acid anhydride.

Nitric oxide is a polar compound. It remains very much polar while nitrogen and oxygen are non polar.

Nitrogen is sp hybrized, this leads to a very short bond and does not easily interact with oxygen and nitrogen


A car changes its velocity from 0 m/s to 14 m/s in 2 seconds.
What is the acceleration

Answers

Answer:

7

Explanation:

You divide the 14m/s by 2 and get the answer of the acceleration of 7

I need help explaining what are the differences between Solids, Liquids, and Gases.

Answers

Explanation: solids are frozen like if you freeze tea it becomes a solid , liquids is like tea and gases is like when you boil water and it becomes a gas

If 0.64 mol PCl5 is placed in a 1.0 L flask and allowed to reach equilibrium at a given temperature, what is the final concentration of Cl2 in the flask?

PCl5 (g)→ PCl3 (aq) + Cl2 (g) Kc= 0.47

Answers

Answer: The final concentration of [tex]Cl_2[/tex] at equilibrium is 0.36 M

Explanation:

Moles of  [tex]PCl_5[/tex] = 0.64 mole  

Volume of solution = 1.0 L

Initial concentration of [tex]PCl_5[/tex] = [tex]\frac{moles}{Volume}=\frac{0.64mol}{1.0L}=0.64 M[/tex]

The given balanced equilibrium reaction is,

                     [tex]PCl_5(g)\rightleftharpoons PCl_3(g)+Cl_2(g)[/tex]

Initial conc.       0.64 M         0M        0M  

At eqm. conc.     (0.64-x) M   (x) M      (x) M

The expression for equilibrium constant for this reaction will be,

[tex]K_c=\frac{[Cl_2]\times [PCl_3]}{[PCl_5]}[/tex]  

Now put all the given values in this expression, we get

[tex]0.47=\frac{(x)\times (x)}{(0.64-x)}[/tex]

By solving the term 'x', we get :

x = 0.36

Thus, the final concentration of [tex]Cl_2[/tex] at equilibrium is x = 0.36 M

The concentration of Cl2 is 0.36M.

Number of moles of PCl5 = 0.64 mol

Volume =  1.0 L

Concentration of PCl5 = 0.64 mol/1.0 L  = 0.64  M

The equation of the reaction is;

          PCl5 (g)→ PCl3 (aq) + Cl2 (g)

I         0.64            0                0

C       -x                 +x               +x

E     0.64 - x           x                  x

Kc = [PCl3] [Cl2]/[PCl5]

0.47 = x^2/0.64 - x

0.47(0.64 - x) =  x^2

0.3 - 0.47x =x^2

x^2 +  0.47x - 0.3 = 0

x = 0.36 M

The concentration of Cl2 is 0.36M.

Learn more about concentration:https://brainly.com/question/1195122

What happens to algae when the temperature in the ocean becomes too hot?
O The algae are susceptible to infection.
O The algae become pale.
O The algae photosynthesize faster.
O The algae lose their ability to photosynthesize

Answers

Answer:

The algae lose their ability to photosynthesize.

Explanation:

Because the algae turn the energy from the sunlight into chemicals.

Hoped this helped!

explain why the definition of philosophy as the love of wisdom in insufficient?​

Answers

Answer:

The word “philosophy” literally means the “love” (philo in Greek) of “wisdom” (sophia). So, a philosopher is somebody who loves wisdom. This, of course, leaves us with 2 important questions: What is wisdom? And what does it mean to love wisdom?

The idea of philosophy goes all the way back to ancient Greece. It is said that the philosopher Pythagoras in the 6th century BCE was the 1st to call himself a philosopher—a philosophos, or “lover of wisdom.” In calling himself this, he was not claiming to be wise. Instead, he was merely saying that he was somebody who valued or cherished wisdom.

Later, the philosopher Plato, who lived in the 5th century BCE, explored these ideas in more depth. In a text called the Symposium, Plato claimed that a philosopher was somebody who was “between the wise and the ignorant.” In other words, a philosopher cared about wisdom but also knew that they were ignorant (we will see tomorrow how Plato was influenced in this by his teacher, Socrates).

Explanation:

Please answer ASAP! thanks

Answers

The answer is g your welcome
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