I want to know how I do excess reactant and limiting reactant. Image provided below.

Limiting Reactant is going to be NaOH or HCl with given lowest moles. Excess will be the ones with more.

Explanation:

Excess and Limiting reactants are based on the amount you could make in an ideal reaction. M (molarity) is the concentration of the given solutions where moles in the amount (the important part) you have of each. If you only have 0.0100 mol NaOH while you have 0.0400 mol HCl the most a reaction has the potential to use is that 0.0100 mol NaOH, thus making it the limiting reactant as it is limiting the possible amount made. The excess here is 0.0300 mol HCl.

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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