Oxalic acid dihydrate, h2c2o4.2h2o, is often used as a primary standard for the standardization of base solutions. for a procedure comparable to this experiment, approximately how many grams of oxalic acid dihydrate should be used in order to have a volume of about 15ml of naoh solution (approximately 0.15m) for the tiration? the acid is diprotic (two h+ reacts).

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."

1. a)c-14 has two more protons

2. d)they have different numbers of protons, neutrons, and valence electrons; they are all gases at room temperature.

3. c) iron and nickel.