As you move across the periods from left to right on the periodic table, the atomic radius decreases. why?
a. the valence electrons are located further away from the nucleus so they experience less effective nuclear charge.
b. the effective nuclear charge increases and pulls the valence electrons closer to the nucleus.
c. the valence electrons are found in higher energy levels.

What is the density of the black hole

Enzymes affect the reactions in living cells by changing the

Cryolite, na3alf6(s), an ore used in the production of aluminum, can be synthesized using aluminum oxide. start this question by first balance the chemical equation.1.) balance the equation: - alo3(s)+naoh(l)+hf(> na3alf6+h2o(g). 2.) if 17.5 kilograms of al2o3(s), 51.4 kilograms of naoh(l), and 51.4 kilograms of hf(g) react completely, how many kilograms of cryolite will be produced? 3.)which reactants will be in excess, (al2o3, naoh, or hf) 4.)what is the total mass of the excess reactants left over after the reaction is complete in kg?