I need help ASAP Which pair of elements is most likely to form an ionic compound with each other? Thank you A) potassium, calcium
B) oxygen, nitrogen
C) sulfur, oxygen
D) calcium, chlorine
E) iron, potassium

It’s the energy source of stars

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.

The mole ratio of hydrogen to ammonia is 3: 2.