If there are 17 protons and 18 neutrons how man electrons are there?

17 protons, 18 neutrons, 18 electrons
There are 18 electrons due to the negative charge: 17-(-1) = 18.15 Aug 2020

Answerδh > 0explanationc₆h₆  (s)  → c₆h₆ (l)if you are changing it from a solid to a liquid, you are pretty much melting the solid. this requires heat energy. therefore, the reaction is endothermic (takes in energy); the system enthalpy increases as the reaction proceeds: δh > 0.