20 point question

the image compares the arrangement of electrons in two different neutral atoms.

which of the following best explains the position of the two atoms in the periodic table?

both atoms have an estimated zeff of 1; therefore, atom d is to the right of atom e in the same period.

both atoms have zeff of 1; therefore, atom d is above atom e in the same column because of the additional energy level.

atom d has an estimated zeff of 1 and is therefore to the left of atom e, which has a zeff of 9.

atom d has an estimated zeff of 1 and is therefore below atom e in the same column, which has a zeff of 9.

Answer asap need by wednesday morning explain how a buffer works, using an ethanoic acid/sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.