To begin with, as Delta H = variation in enthalpy is >0 , it means rxn is endothermic.
The rule says: Delta U = Delta H + W = 186 -179 = 7 kJ.
Where Delta U is variation in internal energy and W is the work done.
Answer: To calculate the number of molecules and atoms in a water drop, you need to know the chemical formula of water. There are two atoms of hydrogen and one atom of oxygen in each water molecule, making the formula H 2 O. So, each molecule of water contains 3 atoms. Molar Mass of Water
Explanation: Hope this helps!
From: Kenma! ^^
Answer:
O-18 is used as a tracer in many hydrologic studies. It is most often used as a component in a mixing-model and hydrograph separation, as O-18 acts conservatively and is applied naturally and uniformly over broad areas. O-18 can be used when different sources (old water/new water) have different isotopic values.
