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:
7.53×10²³ molecules
Explanation:
Given data:
Number of moles of carbonic acid = 1.25 mol
Number of molecules of CO₂ produced = ?
Solution:
Chemical equation:
H₂CO₃ → CO₂ + H₂O
Now we will compare the number of moles of carbonic acid with CO₂ from balanced chemical equation.
H₂CO₃ : CO₂
1 : 1
1.25 : 1.25
Number of molecules can be determine by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
Number of molecules:
1 mole = 6.022 × 10²³ molecules
1.25 mol × 6.022 × 10²³ molecules / 1 mol
7.53×10²³ molecules
Answer:
D. 0.36 g
Explanation:
When a gas is collected over water, the total pressure is the sum of the pressure of the gas and the pressure of the water vapor.
Ptotal = Pwater + PN₂
PN₂ = Ptotal - Pwater = 730 torr - 23.76 torr = 706 torr
We can find the mass of N₂ using the ideal gas equation.
Answer:
It is prepared small amounts of hydrogen cloride for uses in the lab.
It can be "generated in an HCl generator by dehydrating hydrochloric acid with either sulfuric acid or anhydrous calcium chloride."
Answer:
? can u explain. Not sure what ur asking
Explanation:
