every atom does have a valence shell but some are stable gases. careful with the numbers. try using a periodic table to ensure your answer and rmb 1cm3 is 1cm x 1cm x 1cm. dont just x3 it. many people make these mistakes
i dont know much of titration but i do know an equation that may help you.
to solve for a Henderson-Hasselbalch equation:
maybe you can go study a little more on the subject. it will also help if you show us your own attempts to the questions.
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