Converting Grams to Milliliters

Date: 05/12/2006 at 17:34:29
From: Sue
Subject: mom with grams problem

I need to know how many ml you would get out of 35g of flour?  I'm not
sure how to do that.

Date: 05/12/2006 at 21:29:16
From: Doctor Rick
Subject: Re: mom with grams problem

Hi, Sue.

Since grams are a measure of weight (mass) and milliliters are a 
measure of volume (capacity), this is not simply a matter of unit 
conversion.  It depends on what you are measuring: 35 grams of lead 
would take up a much smaller volume than 35 grams of flour.

You're not cooking with lead, I know, but even saying "flour" is not 
specific enough for this purpose.  I opened my 1975 edition of "The 
Joy of Cooking" to the section on conversions and equivalents, and I 
find that 1 lb of cake flour is 4 3/4 cups, while 1 lb of all-
purpose flour is 4 cups.

I'll convert those to metric units, using other tables in the same 
section.

  1 cup = 236 ml
  1 pound = 454 g

Thus, 

  Cake flour:
    454 g = 4.75 * 236 ml = 1121 ml 
      1 g = 1121 / 454 ml = 2.47 ml
     35 g =  35 * 2.47 ml = 86.4 ml

  All-purpose flour:
    454 g = 4.00 * 236 ml =  944 ml
      1 g =  944 / 454 ml = 2.08 ml
     35 g =  35 * 2.08 ml = 72.8 ml

Those calculations are probably not as precise as I showed them, 
because the equivalents in the cook book are not that precise.  I 
hope this helps.

- Doctor Rick, The Math Forum
  http://mathforum.org/dr.math/