Answer:
Molar mass→ 0.930 g / 6.45×10⁻³ mol = 144.15 g/mol
Explanation:
Let's apply the formula for freezing point depression:
ΔT = Kf . m
ΔT = 74.2°C - 73.4°C → 0.8°C
Difference between the freezing T° of pure solvent and freezing T° of solution
Kf = Cryoscopic constant → 5.5°C/m
So, if we replace in the formula
ΔT = Kf . m → ΔT / Kf = m
0.8°C / 5.5 m/°C = m → 0.0516 mol/kg
These are the moles in 1 kg of solvent so let's find out the moles in our mass of solvent which is 0.125 kg
0.0516 mol/kg . 0.125 kg = 6.45×10⁻³ moles. Now we can determine the molar mass:
Molar mass (mol/kg) → 0.930 g / 6.45×10⁻³ mol = 144.15 g/mol
Answer:
SO42 - Trigonal planar ion
Explanation:
The SO4^2- ion is tetrahedral and not trigonal planar because the sulphur atom has four regions of electron density which includes the lone pair of electrons on sulphur atom.
This accounts for the observed tetrahedral arrangement of electron pairs around the central sulphur atom in SO4^2- ion, hence the answer.
Answer:
a 17 bc it is how it works
Hey there!:
1) The additional stability that accompanies the formation of the network<span>Crystalline is measured as network enthalpy.
</span>2) The reticular energy is the energy released when the solid Crystal isform from separate ions in the gaseous state. Always exothermic.<span>
3) </span>The enthalpy of the network depends directly on the size of the loads and conversely in the distance between the ions .
hope this helps!
