Sciencemadness Discussion Board

What is generally meant by "parts"?

cobraface - 22-8-2018 at 05:49

Hey all,

I want to copy a solution from a publication but am unsure how exactly to prepare it. They say "15 parts X and 85 parts Y". Is this generally meant for mass or volume?

Thank you

ELRIC - 22-8-2018 at 06:14

Do you have a link to the publication?

cobraface - 22-8-2018 at 06:16

Yes here it is. See Experiment section.

https://www.researchgate.net/publication/48210369_Fabricatio...

WGTR - 22-8-2018 at 07:06

It's an ambiguous term that depends on context. If measuring a solid, it's usually by mass, as that is most conventional.

I would lean towards volume in this case. Why? Because you don't normally weigh liquids, but measure them by volume using glassware. Could you imagine spilling some drops of 68% nitric acid on an expensive electronic balance?

It's better for an author to specify mass or volume for clarity. In a way this type of thing is like trying to cook from a recipe. If a recipe calls for 1c. of flour, that means one cup, leveled off at the top of the measuring cup. If the same recipe specifies 1c. of sugar, that means one cup, piled up so that sugar is falling off the sides. Completely different volumes. Better recipes will specify everything in mass so that there is no confusion among those who understandably don't know better.

[Edited on 8-22-2018 by WGTR]

unionised - 22-8-2018 at 10:50

Quote: Originally posted by WGTR  
Could you imagine spilling some drops of 68% nitric acid on an expensive electronic balance?

]


Yes, I could imagine doing that.
It seem likely that the first person to use a weighing bottle imagined something similar.

https://en.wikipedia.org/wiki/Weighing_bottle