Answer:
B: +3
Explanation:
If Gallium loses 3 electrons, it will become an ion.
The ion will be positively charged because in this new ion, the number of electrons is lesser than the number of protons. The charge difference will impart a positive net charge on the ion.
- In a neutral atom, the number of electrons and protons are the same.
- For positively charged ions, the number of protons is greater than the electrons
If Gallium the loss of 3 electrons offsets the charge balance in the chemical specie. Thus, the ion will have a net +3 charge.
Hydrogen bonds are present in the following molecules: HF AND NH3
Dipole dipole inter molecular forces occurs the molecules of H2S AND H2.
Hydrogen bonding is an electrostatic attraction between two polar groups that occur when hydrogen atom covalently bound with highly electronegative atoms.
Answer: cycloaddition of 1,3-butadiene and allyl anion is thermally allowed.
Explanation:
Using the frontier molecular orbital approach, we consider if the symmetry of the LUMO of the diene (1,3-cyclobutadiene) and the HOMO of the dienophile allyl anion), match each other since the diels alder reaction is a symmetry allowed process. The symmetries of these frontier molecular orbitals match each other hence the reaction is thermally allowed. It should be notes that 4+2 cycloadditions are thermally allowed although they are slow.