Why is the spot of drink placed above the water line at the start of the process

Chemistry

2 answers:

Elena L [17]3 years ago

4 0

This is the answer. Hope this helps!

Klio2033 [76]3 years ago

3 0

Answer: The solvent gives extra energy to pull up the sample and the sample will also dissolve in the solvent. That's why as precautionary measure start line should stay above the solvent in chromatography.The baseline must be above the solvent level in the TLC chamber, so the solvent does not dilute to samples so much that they dissolve.

Explanation:

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At 311 K, this reaction has a K c value of 0.0111 . X ( g ) + 2 Y ( g ) − ⇀ ↽ − 2 Z ( g ) Calculate K p at 311 K. Note that the

Aleks [24]

Answer:

$K_{p}=4.35\times 10^{-4}$

Explanation:

We know, $K_{p}=K_{c}(RT)^{\Delta n}$

where, R = 0.0821 L.atm/(mol.K), T is temperature in kelvin and $\Delta n$ is difference in sum of stoichiometric coefficient of products and reactants

Here $\Delta n=(2)-(2+1)=-1$ and T = 311 K

So, $K_{p}=(0.0111)\times [(0.0821L.atm.mol^{-1}.K^{-1})\times 311K]^{-1}=4.35\times 10^{-4}$

Hence value of equilibrium constant in terms of partial pressure $(K_{p})$ is $4.35\times 10^{-4}$

4 0

3 years ago

If the change in entropy of the surroundings for a process at 451 k and constant pressure is -326 j/k, what is the heat flow abs

Arisa [49]

If the change in entropy of the surroundings for a process at 451 k and constant pressure is -326 j/k, then heat flow absorbed (in kj) by the system is -147.026kJ.

<h3>What is entropy? </h3>

The entropy of particle is defined as how random it move. It shows the randomness of the system or may be disorders of the system. It is used to measure the unavailable energy for performing useful work.

Unit of entropy = J/K

<h3>Formula:</h3>

∆s = ∆Q/T

where,

∆s = change in entropy of the surrounding = -326J/K

∆Q = heat absorbed from surrounding

T = Temperature = 451K

∆Q = ∆s × T

∆Q = -326 × 451

∆Q = 147,026 J

∆Q = 147.026 kJ

Thus we find that the heat absorbed by the system is 147.026 kJ.