Answer:
Both electrons of Mg should be transferred to one O.
Explanation:
This is because metals like to lose electrons whereas non metals like to gain electrons in an ionic compound. MgO is an ionic compounds. So Magnesium being a metal in group 2 of periodic table, it wants to donate 2 electrons to get to the octet rule, so it donates its electrons and oxygen accepts them to fill its octet rule.
Answer:
Option A = pure water
Explanation:
The pure water will have the lowest boiling point as compared to the other given solution.
Reason:
The pure water is just the solvent while other given options are solution which means that solute is present in it. The vapor pressure of the solvent goes to decrease when solute is added. Thus boiling point is increases because more heat is needed in order to create the vapor pressure equal to the external pressure.
The boiling points of solvents thus changes above the solution as the concentration of solute varies. In given solutions the 2.0 m NaCl will have highest boiling point because of high concentration of sodium chloride while 0.5 m NaCl will have lowest boiling point after the pure water.
Mathematical expression:
ΔT = Kbm
ΔT = change in the boiling point
Kb = Boiling point elevation constant
m = molal concentration of solute
The change in the boiling point of solvent above solution will directly proportional to the solute concentration.
Answer:
Formula weight of H₂O molecule is 18.02 amu.
Explanation:
Given data:
Formula weight of H₂O = ?
Atomic mass of H = 1.008 amu
Atomic mass of O = 16.00 amu
Solution:
Formula weight:
"It is the sum of all the atomic weight of atoms present in given formula"
Formula weight of H₂O = 2×1.008 amu + 1×16.00 amu
Formula weight of H₂O = 18.02 amu
Thus, formula weight of H₂O molecule is 18.02 amu.