# Lab Report Enthalpy: volume of droplet

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In order to find the enthalpy (the energy needed to evaporate a certain substance) I need to know the exact volume/mass.

What is the volume of a normal drop from a droplet? Does the volume depend on the substance too?

I should have found that out while I was doing the lab, but now I need your help to survive [iBsurvival ]

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Wait, didn't you measure the volume when you conducted the experiment? For example 50 mL of HCl and 50 mL of NaOH then just add them up to 100 mL.

1 droplet from a dropper should be around 0.1 mL, if I am not mistaken. Please correct me if I am wrong. I think the volume of 1 droplet from a dropper should always be 0.1 mL no matter what substance is in the dropper.

Btw you can find the volume if you know the concentration and number of mol; or if you know the mass, the density is usually assumed to be that of water (1 g dm-3).

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Wait, didn't you measure the volume when you conducted the experiment? For example 50 mL of HCl and 50 mL of NaOH then just add them up to 100 mL.

It has nothing to do about that. Only the volume of a drop from a droplet

I need more answers to be sure!

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I am not sure what you used exactly. Did you use a dropping pipette?

There are the information I have, hope they help.

For water or any liquid with a similar viscosity, 20 droplets= 1 ml. Which means 1 drop is 0.05 ml.

5 drops from a dropping pipette are 1 ml. (1 droplet= 0.2g)

That being said, it depends on the type of liquid and its viscosity as well.

Is the liquid you're talking about water?

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I am not sure what you used exactly. Did you use a dropping pipette?

That being said, it depends on the type of liquid and its viscosity as well.

Is the liquid you're talking about water?

The liquids I'm talking about are as follows: 1-propanol, 2-propanol, 1-pentanol, 1-butanol, methanol, ethanol, heptane, decane, octane, gasoline, deionized water. And I think a dropping pipette is the same thing as a droplet, so yes, I used a dropping pipette.

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Ok, then this is the information I got from my chemistry teacher and I pretty much trust him on any question.

5 drops from a dropping pipette are 1 ml. (1 droplet= 0.2g)

However, if you're unsure yet, ask some more. Make sure you mention it in your lab report though.

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Ok, then this is the information I got from my chemistry teacher and I pretty much trust him on any question.

5 drops from a dropping pipette are 1 ml. (1 droplet= 0.2g)

However, if you're unsure yet, ask some more. Make sure you mention it in your lab report though.

There actually a standard unit for a drop

drop (Imperial) gtt ≡ 1/288 fl oz (Imp) = 98.656 467 013 8 × 10−9 m3

drop (Imperial) (alt) gtt ≡ 1/1 824 gi (Imp) ≈ 77.886 684 × 10−9 m3

drop (medical) ≡ 1/12 ml = 83.03 × 10−9 m3

drop (metric) ≡ 1/20 mL = 50.0 × 10−9 m3

Of course use the metric one! Peace out!

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Thank you guys ,

The critical idea in this lab was that the volume of a drop depends on a substance's' viscosity. If a substance has high viscosity then you get small drops from it etc...

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