How many valence electrons does the 1st group of the periodic table have

According to the vsepr theory what is the shape of a molecule that has a central atom valence three other items with no lone pairs of electrons

How many mmols of tris-hcl are there in 100 ml of a 100 mm tris-hcl buffer solution at ph 8.1? note that the 100 mm refers to the sum of tris and tris-hcl concentrations?

Which type of precipitation would most likely form when the surface air temperature is slightly below freezing and the air temperature increases as you move upward away from the ground?