Answer:
The right choice is c. Water molecules have a weakly positive hydrogen end.
Explanation:
The unequal sharing of electrons in water molecule gives a slight negative charge near its oxygen atom ( see image below) and a slight positive charge near its hydrogen atoms. A neutral molecule that has a partial positive charge at one end and a partial negative charge at the other, it is a polar molecule.
so
a. Water molecules have a nonpolar bond.
It is wrong choice because water has polar bond .
b. Water molecules have a weakly positive oxygen end.
Also, a wrong choice due to water molecule gives a slight negative charge near its oxygen atom.
c. Water molecules have a weakly positive hydrogen end.
This is the right choice.
d. Water molecules have two oxygen and two hydrogen atoms
It is wrong choice because water has one oxygen and two hydrogen atoms
<u>So, the right choice is</u>
c. Water molecules have a weakly positive hydrogen end.
Answer:

Explanation:
- State of benzene at RTP = liquid
- State of chloroform at RTP = liquid
- Boiling point of benzene = 80.1 °C
- Boiling point of chloroform = 61.2 °C
Since, both of the chemicals are liquids, we can separate it by the process of distillation.
<u>Distillation:</u>
- is the process in which we separate two liquids on the basis of their difference in boiling points.
<u>How it works:</u>
Since chloroform has less boiling point, it will evaporate and collected first and benzene will follow it after sometime.
- Apparatus of distillation is in the attached file.
![\rule[225]{225}{2}](https://tex.z-dn.net/?f=%5Crule%5B225%5D%7B225%7D%7B2%7D)
1 mole of NH42SO4 contains 42 moles of H. We take the 42 moles of H and multiply that times Avogadro's number (6.02x10^23) and get 2.5284x10^25 atoms of hydrogen
Mass of oxygen = 143,1g - (53,4g + 16,9g + 43g) = 29,8g
If 143,1g ------ is ------ 100%
so
29,8g ------- is ------ %O
%O = (29,8g*100%) / 143,1g = 20,82%