Consider 100 moles of a gas stream containing 15 mol% CS2, 18 mol% O2, and 67 mol% N2. The gas is fed to a continuous absorption tower, where it contacts liquid benzene, which absorbs CS2, but not O2 or N2. Benzene is fed to a column in a 2:1 mole ratio to the feed gas. Some of the benzene entering as liquid evaporates and leaves the top of the tower as vapor. The gas leaving the absorber contains 2 mol% CS2 and 2 mol% benzene. How many independent material balances can you write

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

that's it!

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