J. J. Thompson discovered the first subatomic particle, , by deflecting a "cathode ray" beam with an electric field. Robert Millikan later determined that
particle's charge in his "oil drop" experiments.
A) the proton
B) the nucleus
C) the neutron
D) the electron

The atomic radius of sodium is 186 pm and of chlorine is 100 pm. the ionic radius for na+ is 102 pm and for cl– is 181 pm. in going from na to cl in period 3, why does the atomic radius decrease while the ionic radius increases? a. the inner electrons in the sodium cation shield its valence electrons more effectively than the inner electrons in the chloride anion do. b. the inner electrons shield the valence electrons more effectively in the chlorine atom than in the chloride anion. c. the outermost electrons in chloride experience a smaller effective nuclear charge than those in the sodium cation do. d. the outermost electrons in chloride experience a larger effective nuclear charge than those in the sodium cation do. e. monatomic ions are bigger than the atoms from which they are formed.

Write the empirical chemical formula of calcium with a mass percent of 38.8, phosphorus with a mass percent of 20.0, and oxygen with a mass percent of 41.3.

Consider the directing effects of the substituents on salicylamide and predict the possible structures of the iodination products. which do you think will be the major product?