Answer:
I. 1.743mg/mL
II. 0.174g
III. 8.7 wt%
Explanation:
As absorbance is directly proportional to concentration. The calibration curve was:
Y = 1.6421X - 0.1113
<em>Where Y is absorbance of sample and X its concentration in mg/mL</em>
The diluted sample obtains an absorbance of 0.461, that means its concentration is:
0.461 = 1.6421X - 0.1113
0.3485mg/mL = X
I. The sample was diluted to 50.0mL from an aliquot of 10.0mL, thus, concentration in the original fruit sample was:
0.3485mg/mL × (50.0mL / 10.0mL) =<em> 1.743mg/mL </em>
II. The total mass of vitamin C in the sample (100.0mL) is:
100.0mL × (1.743mg/mL) = 174mg = <em>0.174g</em>
III. As the fruit sample was of 2.0g, the wt% is:
0.174g / 2.0g = <em>8.7 wt%</em>
Answer:
A. Polar regions receive less solar energy and heat per unit area than tropical regions.
Explanation:
The sun is lower in the sky the farther away from the equator you go (at higher latitudes), so the solar energy is less direct. Climate in areas with less direct solar input tends to be generally cooler.
The answer is: molecular polarity.
Paper chromatography is an analytical method used to separate colored substances.
Substances are distributed between a stationary phase and a mobile phase.
Substances have different chemical structures and because of that, the different polarity, so each molecule have a different solubility in the solvent.
If a substance is very nonpolar, it will not dissolve at all in a very polar solvent.
If water (polar substance) is a solvent, the more polar the color, the higher it will rise on the papers.