Posted by annie on Monday, September 20, 2010 at 4:22pm.
Thanks a lot:)
So just to confirm: normally for any chemical bought from manufacturer, if it is not stated, the % usually means v/v? Seems like for conc sulphuric acid, when it is stated 97% sulphuric acid, it means 97% w/w sulphuric acid?
Thank you very much.
Posted by annie on Monday, September 20, 2010 at 10:33am.
I have a bottle of 95% ethanol purchased from the manufacturer.
Normally, when it is not stated, does it mean 95% w/w ethanol?
I need to prepare 100ml of 40% v/v ethanol solution from 95% ethanol.
Please show me the calculation steps.
Chemistry -repost thank you in advance - bobpursley, Monday, September 20, 2010 at 11:01am
when not stated, 95% is v/v
you want to dilute the ethanol 95/45 times, or 2.111 times. THat means one part alcohol, and 1.111 parts water.
100ml/2.111=47.37 is a part.
so, 47.37 ml of 95%
52.63 ml of water.
- Chemistry - v/v versus w/w - DrBob222, Monday, September 20, 2010 at 5:18pm
I think your conclusion is wrong. You are correct that the percent on a bottle of H2SO4 means w/w. Technically, ALL manufacturers (and problem makers) should state 95% v/v or 98% w/w (or 95% w/v) but they don't. USUALLY one means w/w if it isn't stated but USUALLY one means v/v if it is two liquids (as in 95% ethanol)(which flies in the face of the H2SO4 bottle).
Answer this Question
More Related Questions
- Chemistry problem - I refer to my earlier post on v/v versus w/w. I would be ...
- Science, Chemistry - I have been told that to prepare 1L of 70% H2SO4 from ...
- chemistry - concentrated aqueous sulphuric acid is 98% sulphuric acid by mass ...
- Chemistry help needed - How do I prepare 90% formic acid from conc. formic acid...
- CHEMISTRY - If 15g of Sodium Hydroxide are treated with sulphuric acid to ...
- Chemistry - Why is conc. Sulphuric acid used as a drying agent? Is it because it...
- Chemistry - 0.2 Faradays of electricity were passed through solutions of ...
- Chemistry - How to prepare 50% of Sulphuric Acid from 10N of Sulphuric Acid
- chemistry - If the molar mass of ASA is 180.2 g/mol, how many moles of ASA were ...
- chemistry - a solution of sulphuric acid is titrated (allquot 20.0ml) with a ...