Read the given expression.
x = atomic number − number of core electrons
which of the following explains the identity of x and its trends down a group?
a). x is the effective nuclear charge, and it remains constant down a group.
b). x is the screening constant, and it remains constant down a group.
c). x is the effective nuclear charge, and it increases down a group.
d). x is the screening constant, and it increases down a group.

Asolution contains 225 g of sodium chloride, nacl, dissolved in enough water to make a 0.25 l of solution. what is the molarity of the solution?

Solutions of sodium carbonate and silver nitrate react to form solid silver carbonate and a solution of sodium nitrate. a solution containing 3.50 g of sodium carbonate is mixed with one containing 5.00 g of silver nitrate. how many grams of sodium carbonate, silver nitrate, silver carbonate, and sodium nitrate are present after the reaction is complete?

The picture represents the process that produces most of the energy used by living organisms on earth. which process is represented in the picture? a) the magnetic attraction between two hydrogen nuclei. b) the fusion of hydrogen nuclei to produce a helium nucleus in the core of the sun. c) the fission of hydrogen nuclei to produce a helium nucleus in the core of the sun. d) the chemical reaction between hydrogen nuclei to produce a helium nucleus in earth's atmosphere.