Explanation:
As the total concentration is given as 1.2 mM. And, it is also given that salt present in the solution is NaCl.
As sodium chloride is an ionic compound so, when it is added to water then it will dissociate into sodium and chlorine ions as follows.
So, it means in total there will be formation of 2 ions when one molecules of NaCl dissociates.
Therefore, concentration of chlorine ions will be calculated as follows.
Concentration of 
ions = 
= 0.6 mM
Thus, we can conclude that the concentration of chloride ions is 0.6 mM.
Answer:
(1). The vapor pressure is 91 mmHg at 20°C.
(2). No, benzene will not boil at sea level.
Explanation:
Benzene, C6H6 is an aromatic, liquid compound with with molar mass of 78.11 g/mol and Melting point of 5.5 °C. One of the importance or the uses of benzene is in the making of fibres and plastics.
The vapour pressure of benzene can be gotten from the table showing the vapor pressure of different liquids.
Boiling point can simply be defined as the point or the temperature in which the vapor pressure is the same with the atmospheric pressure.
The atmospheric pressure is 760mmHg, while the vapor pressure at sea level is at the temperature of 15°C which is equal to 71 mmHg( from the table showing the vapor pressure of different liquids).
71 mmHg is not equal to 760 mmHg, thus, at sea level Benzene will not boil.
Answer: alkaline earth metals (group-IIA)
Explanation:
The element which donates the electron is known as electropositive element and forms a positively charged ion called as cation. The element which accepts the electrons is known as electronegative element and forms a negatively charged ion called as anion.
Alkaline earth metals donate 2 valence electrons to acquire noble gas configuration.
For example: Berrylium is the first alkaline earth metal with atomic number of 4 and thus has 4 electrons
Electronic configuration of berrylium:
![[Be]:4:1s^22s^2](https://tex.z-dn.net/?f=%5BBe%5D%3A4%3A1s%5E22s%5E2)
Berrylium atom will loose two electrons to gain noble gas configuration and form berrylium cation with +2 charge.
![[Be^{2+}]:2:1s^2](https://tex.z-dn.net/?f=%5BBe%5E%7B2%2B%7D%5D%3A2%3A1s%5E2)
Thus Elements donate 2 electron to produce a cation with a 2+ charge are alkaline earth metals.
Anyone else just hate chemistry
