D. One chimp cleaning and grooming the hair of another chimp
Marie Curie discovered polonium and radium. Hope this helps:))) Please, mark Brainliest!
Answer:
ΔH = - 272 kJ
Explanation:
We are going to use the fact that Hess law allows us to calculate the enthalpy change of a reaction no matter if the reaction takes place in one step or in several steps. To do this problem we wll add two times the first step to second step as follows:
N2(g) + 3H2(g) → 2NH3(g) ΔH=−92.kJ Multiplying by 2:
2N2(g) + 6H2(g) → 4NH3(g) ΔH=− 184 kK
plus
4NH3(g) + 5O2(g) → 4NO(g) +6H2O(g) ΔH=−905.kJ
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2N2(g) + 6H2(g) + 5O2(g)→ 4NO(g) + 6H2O(g) ΔH = (-184 +(-905 )) kJ
ΔH = -1089 kJ
Notice how the intermediate NH3 cancels out.
As we can see this equation is for the formation of 4 mol NO, and we are asked to calculate the ΔH for the formation of one mol NO:
-1089 kJ/4 mol NO x 1 mol NO = -272 kJ (rounded to nearest kJ)
The ion composition of Magnesium is 12,10, 2+.
Magnesium is a chemical element with symbol Mg and an atomic number 12, it has 12 protons, and 12 electrons with a chemical configuration of 2:8:2. It requires to loose two electrons to form a stable configuration forming a cation (positively charged ion) with a charge of +2 and a configuration of 2:8 ( 12 protons and 10 electrons).
