I have drawn Lewis structures for hydrogen cyanide and cyanogen. I need to state the noble gas (for each element) whose electron configuration is attained in the Lewis structures. Can anyone help as I am quite confused! Many thanks

Previous posts have asked for the noble gas configuration FOR THE MOLECULE and I have reponded that I have never heard of that. I have heard of elements being isoelectronic with a noble gas but not molecules. Yours is the first post that asks for the noble gas of each element.
For HCN, H is sharing two electrons; therefore,it is like He. C is sharing 8 electrons, it has 2 in the innner shell which makes 10 so it is isoelectronic with Ne. N has 2 electrons in the inner shell, it is sharing 8 so it is isoelectronic with Ne. You can do (CN)2 the same way.

in what way does calorimetry make use of law of conservation of energy?

heat lost by one material = heat gained by another.
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