Answer:
127.3° C, (This is not a choice)
Explanation:
This is about the colligative property of boiling point.
ΔT = Kb . m . i
Where:
ΔT = T° boling of solution - T° boiling of pure solvent
Kb = Boiling constant
m = molal (mol/kg)
i = Van't Hoff factor (number of particles dissolved in solution)
Water is not a ionic compound, but we assume that i = 2
H₂O → H⁺ + OH⁻
T° boling of solution - 118.1°C = 0.52°C . m . 2
Mass of solvent = Solvent volume / Solvent density
Mass of solvent = 500 mL / 1.049g/mL → 476.6 g
Mol of water are mass / molar mass
76 g / 18g/m = 4.22 moles
These moles are in 476.6 g
Mol / kg = molal → 4.22 m / 0.4766 kg = 8.85 m
T° boling of solution = 0.52°C . 8.85 m . 2 + 118.1°C = 127.3°C
Answer:
Equal volumes of SO2(g) and O2(g) at STP contain the same number of molecules
Explanation:
According to Avogadro Law,
Equal volume of all the gases at same temperature and pressure have equal number of molecules.
This law state that volume and number of moles of gas have direct relation.
When the amount of gas increases its volume will increase and when the amount of gas decreases its volume will decrease.
Mathematical relation:
V ∝ n
V/n = K
K is proportionality constant.
When number of moles change from n₁ to n₂ and volume from V₁ to V₂
expression will be,
V₁/n₁ = K , V₂/n₂ = K
V₁/n₁ = V₂/n₂
Answer:
Here's what I get.
Explanation:
At the end of the reaction you will have a solution of the alcohol in THF.
The microdistillation procedure will vary, depending on the specific apparatus you are using, but here is a typical procedure.
- Transfer the solution to a conical vial.
- Add a boiling stone.
- Attach a Hickman head (shown below) and condenser.
- Place the assembly in in the appropriate hole of an aluminium block on top of a hotplate stirrer.
- Begin stirring and heating at a low level so the THF (bp 63 °C) can distill slowly.
- Use a Pasteur pipet to withdraw the THF as needed.
- When all the THF has been removed, raise the temperature of the Al block and distill the alcohol (bp 143 °C).
By nonmetals, metals, and gases
Answer: 625 grams
Explanation:
14 goes into 56, 4 times.
10,000÷2=5,000 - first half life
5,000÷2=2,500 - second half life
2,500÷2=1,250 - 3rd half life
1,250÷2= 625 - 4th half life
Note: don't type "grams" after 625, just type "625".
