A hydrated substance will decrease in mass when heated since the water is being boiled away.
I hope this helps. Let me know if anything is unclear.
Explanation:
Given -
- An organic compound gives H₂ gas with Na
- On treatment with alkaline iodine it gives yellow ppt.
- On oxidation with CrO₃/H⁺ forms an aldehyde (C₂H₄O)
To Find -
- Name the compound and write the reaction involved
Now,
Let A be the organic compound.
Then,
- A + Na → + H₂↑
- A + I₂ → CHI₃ (yellow ppt.)
- A + CrO₃ + H⁺ → C₂H₄O
Now,
Here we see that compound A reacts with chromic oxide (CrO₃) in the presence of acidic medium gives aldehyde.
- Functional group of aldehyde = —CHO
And It forms only 2 Carbon aldehyde it means, It is Ethanal (CH₃CHO).
Compound A reacts with chromic oxide (CrO₃) in the presence of acidic medium gives ethanal.
It means,
We know that 1° alcohol on oxidation gives aldehyde.
Here it gives 2 Carbon aldehyde.
It means,
Here 2 Carbon and 1° alcohol is used.
Now,
Its cleared that Compound A is Ethanol.
Reaction Involved -
- CH₃CH₂OH + Na → CH₃CH₂O⁻Na⁺ + H₂↑
- CH₃CH₂OH + I₂ + OH⁻ → CHI₃↓ + HCOO⁻ + HI + H₂O
- CH₃CH₂OH + CrO₃ + H⁺ → CH₃CHO
Explanation:
a) Using Beer-Lambert's law :
Formula used :

where,
A = absorbance of solution = 0.945
c = concentration of solution = ?
l = length of the cell = 1.20 cm
= molar absorptivity of this solution =


(
)
14.16 μM is the molarity of the red dye solution at the optimal wavelength 519nm and absorbance value 0.945.
b) 
1 L of solution contains
moles of red dye.
Mass of
moles of red dye:



c) In order to dilute red dye solution by 5 times, we will need to add 1 L of water to solution of given concentration.
Concentration of red dye solution = 
Concentration of red solution after dilution = c'



The final concentration of the diluted solution is 
Solution:
After the reaction of mixture is worked-up Washing three times the organic with sodium carbonate helps to decrease the solubility of the organic layer into the aqueous layer. This allows the organic layer to be separated more easily.
And then the reaction washed by saturated NACL we have The bulk of the water can often be removed by shaking or "washing" the organic layer with saturated aqueous sodium chloride (otherwise known as brine). The salt water works to pull the water from the organic layer to the water layer.
Answer:The boiling point of the solution is 108° C.
Explanation:
Boiling point of pure water=T=
Boiling point of water after addition of 500 g of ethylene glycol=
Mass of water = 500g = 0.5 kg (1000 g = 1 kg)






The boiling point of the solution is 108° C.