Preparation From Constituent Ingredients
It is common practice in laboratories to make a solution directly from its constituent ingredients. There are three cases in practical calculation:
- Case 1: amount of solvent volume is given.
- Case 2: amount of solute mass is given.
- Case 3: amount of final solution volume is given.
- Case 1: amount (mL) of solvent volume VA is given. Solute mass mB = C VA dA /(100-C/dB)
- Case 2: amount of solute mass mB is given. Solvent volume VA = mB (100/C-1/ dB )
- Case 3: amount (mL) of final solution volume Vt is given. Solute mass mB = C Vt /100; Solvent volume VA=(100/C-1/ dB) mB
- Case 2: solute mass is known, VA = mB 100/C
- Case 3: total solution volume is know, same equation as case 1. VA=Vt; mB = C VA /100
Example: Make 2 g/100mL of NaCl solution with 1 L water Water (properties). The density of resulting solution is considered to be equal to that of water, statement holding especially for dilute solutions, so the density information is not required.
mB = C VA =( 2 / 100 ) x 1000 =20 g
Famous quotes containing the words ingredients and/or preparation:
“This even-handed justice
Commends th ingredients of our poisoned chalice
To our own lips.”
—William Shakespeare (15641616)
“With memory set smarting like a reopened wound, a mans past is not simply a dead history, an outworn preparation of the present: it is not a repented error shaken loose from the life: it is a still quivering part of himself, bringing shudders and bitter flavours and the tinglings of a merited shame.”
—George Eliot [Mary Ann (or Marian)