Explanation:
The given data is as follows.
= 211 nm, 
l = 1 cm, 7% < Transmittance < 85%
Suppose the aqueous solution follows Lambert-Beer's law. Therefore,
Absorbance = 
Hence, for 7% transmittance the value of absorbance will be as follows.
Absorbance = 
= 1.155
For 85% transmittance the value of absorbance will be as follows.
Absorbance = 
= 0.07058
According to Lambert-Beer's law.
A = 
where, A = absorbance
= molar extinction coefficient
C = concentration
Therefore, concentration for 7% absorbance is as follows.

= 
= 
= 0.187 mmol/L
Concentration for 85% absorbance is as follows.

= 
= 
= 0.01144 mmol/L
Thus, we can conclude that linear range of phenol concentration is 0.01144 mmol/L to 0.187 mmol/L.
Answer:
Hexane should be used first.
Explanation:
Chromatography is a method of separating the constituents of a mixture by taking advantage of their different rates of movement in a solvent over an adsorbent medium. Chromatography is a means of separation and analysis that utilises fractional separation. It is based on the principle that if a fluid containing a number of substances is allowed to pass though an adsorbent medium, the different substances in the fluid may travel at different rates and be separated.
The rate of movement depends on the relative affinities of the constituents for the solvent and adsorbent medium. i.e solutes which are weakly adsorbed by the adsorbent medium are easily redissolved by the ascending solvent and quickly travel up the adsorbent medium. In addition to that , solutes which are very soluble in the solvent move up at a faster rate than those which are not soluble.
In column Chromatography;
A non-polar solvent should be initiated and applied first. This is because , in a column chromatography, a non-polar compound will be removed at first then later polar compound.
Assuming a polar compound is used first, the polar compounds will be removed alongside with all the non-polar compounds.
From the two Compounds given;
We know that :
Hexane is a non-polar compound and Methylene chloride is a polar compound. As such, Hexane should be used first.
Answer:
See explanation
Explanation:
The reaction to be considered is shown below;
H2CO3<------->CO2 + H2O
We know that when a constraint such as a sudden change in concentration, pressure or temperature is imposed on a reaction system in equilibrium, the system has to adjust itself by shifting in a particular direction in order to cancel the constraint.
Now, if we remove CO2, the equilibrium position must shift to the right by the decomposition of more H2CO3 to establish equilibrium again.
Answer:
6 mass
Explanation:
because the si unit of gram is mass