In which of the following substances does sharing of electrons between two atoms occur? a. kcl (l is supposed to be a lower case l) b. ar c. au d. cr2o7^2- ( answer quickly. you in advance.)

Answer

The correct option is D.   Cr2O7^2-

Explanation:

The covalent bond between the two atoms formed when mutual sharing of electrons take place.As in dichromate ion, covalent bond is present which shows sharing of electrons between two atoms Cr and O.KCl is ionic bond, in this case, K completely donate electrons while Cl completely accept the electrons. So we can not say sharing of electrons.Ar and Au are present in free form, not forming bond with others atoms, so we cant say any sharing of electrons.

1.60.

Explanation:

The no. of millimoles of HCl = MV = (0.15 M)(20.0 mL) = 3.0 mmol.The no. of millimoles of KOH = MV = (0.10 M)(20.0 mL) = 2.0 mmol.

Since the no. of millimoles of HCl is larger than that of KOH. The solution is acidic.

∴ M of remaining HCl [H⁺] remaining = (NV)HCl - (NV)KOH/V total = (3.0 mmol) - (2.0 mmol) / (40.0 mL) = 0.025 M.

∵ pH = - log[H⁺]

∴ pH = - log[H⁺] = - log(0.025) = 1.602 ≅ 1.60.