List the numbers of protons, neutrons, and electrons in chlorine-18. (3 points) write the electron configuration for a chlorine atom. calculate the total number of electrons in each energy level and state which energy levels are not full. (3 points) what are the three rules that govern the filling of atomic orbitals by electrons? be sure to describe each one, not just name it. (3 points) there are four isotopes of lead and their relative abundance listed below. use this information to calculate the approximate atomic mass of lead. show all work (4 points) 82 protons, 122 neutrons, 1.4% 82 protons, 125 neutrons, 22.1% 82 protons, 124 neutrons, 24.1% 82 protons, 126 neutrons, 52.4% define first ionization energy and describe the trends within groups and across periods in the periodic table. provide examples. (4 points) write the electron configuration for the metalloid in period 3. include the name of the element. (3 points)

The electronic configuration of Chlorine is 1s2 2s2 2p6 3s2 3p5.

There are three energy levels in chlorine

First energy level is n=1 has 1s2 so total 2 electrons

Second energy level is n=2, 2s2 2p6 so total 2+6= 8 electrons

Third has 3s2 3p5 electrons just 7 total... p can contain 6 electrons but only 5 are present. So the third level has lesser number of electrons than that can be filled

- calcium has greater affinity to bond with electron receptors than hydrogen does and hence, it has the ability to replace hydrogen in most of its compounds.

- lithium has 2 valence electrons in the product because it can make only 1 bond with hydrogen. beryllium has 4 valence electrons in the product because it can only make 2 bonds. it has fewer electrons than neon and can react with electron donors. each hydrogen has 2 valence electrons, the same as helium.

- the covalent bond formed between carbon and hydrogen is polar because carbon is more electronegative than hydrogen and it attracts the bonded electron pair closer to itself, thus giving hydrogen a partial positive charge.

- a hydrogen bond is a relatively weak bond that hydrogen atoms make with the electronegative atoms nitrogen, oxygen or fluorine.

so the best choice is a.) 2 calcium (ca) atoms

aquifers are bounded above and below by impermeable rock. the driving force of groundwater movement in confined aquifers is pressure, rather than gravity.