Answer:
The mole fraction of ethanol is 0.6. A 10 mL volumetric pipette must be used for to measure the 10 mL of ethanol. The vessel should be clean and purged.
Explanation:
For calculating mole fraction of ethanol, the amount of moles ethanol must be calculated. Using ethanol density (0.778 g/mL), 10 mL of ethanol equals to 7.89 g of ethanol and in turn 0.17 moles of ethanol. The same way for calculate the amount of water moles (ethanol density=0.997 g/mL). 2 mL of water correspond to 0.11. The total moles are: 0.17+0.11=0.28. Mole fraction alcohol is: 0.17/0.28=0.6
<h3><u>Answer;</u></h3>
D. It decreases and the pH increases.
<h3><u>Explanation;</u></h3>
- pH is a measure of the hydorgen ion concentration of a solution. Solutions with a high concentration of hydrogen ions have a low pH and solutions with a low concentrations of H+ ions have a high pH.
- <em><u>[H+] and [OH-] are inversely related. Therefore; As the concentration of H+ increases the pH decreases. Since the concentrations of H+ and OH- are inversely proportional, as one goes up, the other goes down. </u></em>
- <em><u>Therefore, an increase in OH- concentration will correspond to an increase in pH and a decrease in the concentration of H+.</u></em>
There are 1,000m is 1k. So just move the decimal one position right. 127.56m
There are 10,000cm in 1k. Move the decimal two positions right. 1275.6cm