I believe Calcareous is not a hydrogenous sediment. Hydrogenous sediments are example of marine sediments that are formed directly from chemical processes in sea water. They include, manganese nodules, phophorites, metal sulfides, evaporites and carrbonates. In shallower areas, such as on continental shelves and near islands, rock salt, calcium salts and sulfates may settle on the ocean floor.
This is coordinate (dative) bonding where the nitrogen atom donates 2 electrons to the oxygen but is still chemically bonded.
First, we have to see how K2O behaves when it is dissolved in water:
K2O + H20 = 2 KOH
According to reaction K2O has base properties, so it forms a hydroxide in water.
For the reaction next relation follows:
c(KOH) : c(K2O) = 1 : 2
So,
c(KOH)= 2 x c(K2O)= 2 x 0.005 = 0.01 M = c(OH⁻)
Now we can calculate pH:
pOH= -log c(OH⁻) = -log 0.01 = 2
pH= 14-2 = 12
The conversations need to solve this problem:
1 cal = 4.184 joules
1 Kcal= 1000 calories
1 kj= 1000 joules
or a more direct approach---->> 1 Kcal = 4.184 Kjoules
8.4 kcal (1000 calories/ 1 Kcal) x (4.184 joules/ 1 cal) x (1 Kj/ 1000 joules)= 35.1 Kj
or 8.4 kcal (4.184 Kj/ 1 kcal)= 35.1 Kj (same answer)
