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Anettt [7]
3 years ago
11

In column chromatography (microscale), after loading it with solvent and adsorbent and prior to loading the sample, what level s

hould you allow the solvent to drop to? Why should you not allow the sample to run dry and what is the consequence if you had allowed it to do so?Why would water not be used to elute a column (besides it polarity) in column chromatography?When isolating separated compounds from a column chromatography, what would aid in the identification of compounds in fractions in the TLC analysis?
Chemistry
1 answer:
Nikolay [14]3 years ago
5 0

Answer:

Explanation:

You should allow the solvent to drop to the level of the adsorvent, so it would never run dry.

When you let your sample to run dry it will never finish to flow from the adsorbent depending of it polarity.

Water should not be used because it can dissolve the adsorbent.

You could use another technique to identify the compound, as an infrared or a ultraviolet detector. You can also, if you know the compounds, identify it for the retention time, for example, if you need to detect two compounds, one more polar than the other, and use a polar adsorbent and a non-polar solvent, the first compound to exit the column will be the less polar one, because it will have a bigger interaction with the solvent than the stationary phase (adsorbent) and will go faster, the second will be the more polar one, because it will have a bigger interaction with the stationary phase.

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Calculate to three significant digits the density of dinitrogen monoxide gas at exactly and exactly . You can assume dinitrogen
Ulleksa [173]

Answer:

see explanation below

Explanation:

You miss the part of the temperature and pressure. According to what I found this is held under 30 °C (or 303 K) and 1 atm.

The problem states that we can treat this gas as an ideal gas, therefore, we can use the equation of an ideal gas which is:

PV = nRT (1)

Now, the density (d) is calculated as:

d = m/V (2)

We can rewrite (2) in function of mass of volume so:

m = d*V (3)

Now, the moles (n) of (1) can be calculated like this:

n = m /MM (4)

If we replace it in (1) and then, (3) into this we have the following:

PV = mRT/MM ----> replacing (3):

PV = dVRT/MM ----> V cancels out so finallly:

P = dRT/MM

d = P * MM / RT (5)

The molar mass of N2O is 44 g/mol So, replacing all the data we have:

d = 1 * 44 / 0.082 * 303

d = 1.77 g/L

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2 years ago
If the symbol X represents a central atom, Y represents outer atoms, and Z represents lone pairs on the central atom, the struct
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3 years ago
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ratelena [41]

Answer:

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Explanation:

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2. Concentration of the reactants or pressure of gaseous

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5. Sunlight

The addition of a foreign body to a reaction may influence the speed of the reaction. If a foreign body increases the rate of reaction, it is a called a positive catalyst or simply a catalyst. A negative catalyst is called an inhibitor.

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Kaylis [27]

Answer:

Here

Explanation:

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Explanation:

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