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The rate at which heat is generated inside a chromatographycolumn from friction of flowing liquid is power (watts, W=J/s)= volume flow raterole="math" localid="1656474760665" (m3/s)×pressure drop (pascals, role="math" localid="1656474828044" Pa=kg/[m?s2]).

(a) Explain the analogy between heat generated in a chromatography column and heat generated in an electric circuit (power = current×voltage).

(b) At what rate (watts = J/s) is heat generated for a flow of 1 mL/minwith a pressure difference of3500 bar between the inlet and outlet?

You will need to convert mL/min tom3/s.Also 1 bar=105Pa.

Short Answer

Expert verified

The part (a), part (b) is

(a) See the answer is below step 1

(b) power =5.845 W

Step by step solution

01

Step 1:Chromatography column and heat generated in an electric circuit.

Part (a)

The heat generated in an electric circuit is equal to the product of current and voltage where the current is the rate of flow of charge and the voltage is the potential difference driving charge.

The heat generated in a chromatography column is equal to the product of volume flow rate and pressure drop where the volume flow rate is the rate of flow of liquid and the pressure is pressure difference driving liquid.

02

Step 2:Power calculated using the formula

Part (b)

The power can be calculated using the formula:

power = volume flow rate?pressure drop

First, we need to convert 1mL/min tom3/s :

1mL/min.10-6m3/mL60s/min=1.67·10-8m3/s

Then we need to convert 3500 bars to Pa:

3500bar·105Pa/bar=3.5·108Pa

03

Substitute the values

Now we put values in formula

power=1.67·10-8m3/s·3.5·108Pa

powerlocalid="1656475464467" =5.845W

Here, the final result is

(a) See the answer is below step 1

(b) power=5.845W

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