A 520-gram sample of seawater contains 0.317 moles of NaCl. What is the percent composition of NaCl in the water?

A: 1.1%
B: 2.8%
C: 3.6%
D: 6.1%

Write the symbol for every chemical element that has atomic number greater than 3 and atomic mass less than 12.0 u.

An atom's configuration based on its number of electrons ends at 3p4. another atom has seven more electrons. starting at 3p, what is the remaining configuration? 3p63d34s2 3p43d54s2 3p64s23d3 3p44s23d

Predict the reactants of this chemical reaction. that is, fill in the left side of the chemical equation. be sure the equation you submit is balanced. (you can edit both sides of the equation to balance it, if you need to.) note: you are writing the molecular, and not the net ionic equation. > cacl2(aq) + h20(l)