I Killed My Goldfish! & Soap Scum
Lab Prep Instructions
GENERAL INFORMATION
Experiment Day/Date:
Instructions: Write any calculations in the space provided, and check with the lab instructor if you have
any questions. Check off each item as you prepare it.
Quantity: Amounts indicated are for a pair of students. For solutions that everyone needs, prepare enough
for 18 pairs of CH 106 students. For those that are only needed by a few groups, prepare enough for the
number of groups using it + 2 more.
SOLUTIONS AND CHEMICALS NEEDED
□ 0.25 M HCl (hydrochloric acid) enough for all groups
□ 0.25 M NaOH (sodium hydroxide) enough for all groups
□ 0.25 M CH3COOH (acetic acid), 5 groups
□ 0.25 M C2H3NaO2 (sodium acetate) 5 groups
□ 0.25 M NH3 (ammonia) enough for 5 groups
□ 0.25 M NH4Cl (ammonium chloride) enough for 5 groups
□ 0.25 M Histidine enough for 5 groups
□ 0.25 M Histidine HCl  H2O enough for 5 groups
SOLUTION PREPARATION
□ 10 mL of 0.25 M HCl (hydrochloric acid)
All groups will need this solution.
- dilute solution from concentrated (12.1 M) HCl in DI water and store in a clear glass bottle
_____ groups 
10 mL 0.25 M HCl
 _____ mL total of 0.1 M HCl solution
group
- please round volume of 0.25 M HCl needed to match the nearest volumetric flask volume available
(i.e. to the nearest 500 mL or 1 L). Amount of 0.25 M HCl to prepare: _____ mL
_____ mL vol. flask 
0.25 M HCl
 _____ mL conc. HCl for dilution in _____ mL vol. flask
12.1 M HCl (conc.)
□ 10 mL of 0.25 M NaOH (sodium hydroxide)
All groups will need this solution.
- prepare solution from the solid (FW 40.00 g) and dilute in DI water and store in a clear glass or
plastic bottle (Note: may use 50% wt/wt NaOH instead which doubles the mass to be added.)
1
_____ groups 
10 mL 0.25 M NaOH
 _____ mL total of 0.1 M NaOH solution
group
-please round volume of 0.25 M NaOH needed to match the nearest volumetric flask volume
available (i.e. to the nearest 500 mL or 1L). Amount of 0.25 M NaOH to prepare: _______ L
_____ mL vol. flask 
40.00 g NaOH 0.25 mol

 _____ g NaOH in _____ mL vol. flask
mol
1000 mL
□ 60 mL of 0.25 M acetic acid
- dilute solution from concentrated (17.4 M, glacial, or 99.8%) acetic acid in DI water and store in a
clear or brown glass bottle
_____ groups 
60 mL 0.25 M acetic acid
 _____ mL total of 0.25 M acetic acid solution
group
- please round volume of 0.25 M acetic acid needed to match the nearest volumetric flask volume
available (i.e. to the nearest 500 mL or 1 L). Amount of 0.25 M acetic acid to prepare: _____ mL
_____ mL vol. flask 
0.25 M acetic acid
 _____ mL conc. acetic acid for dilution in _____ L vol. flask
17.4 M acetic acid
□ 50 mL of 0.25 M C2H3NaO2 (sodium acetate)
- prepare solution from the solid (FW 82.03 g/mol) and dilute in DI water and store in a clear or
brown glass bottle
_____ groups 
50 mL 0.25 M C 2 H 3 NaO 2
 _____ mL total of 0.25 M C 2 H 3 NaO 2 solution
group
- please round volume of 0.25 M C2H3NaO2 needed to match the nearest volumetric flask volume
available (i.e. to the nearest 500 mL or 1 L). Amount of 0.25 M C2H3NaO2 to prepare: _____ mL
_____ mL vol. flask 
82.03 g C 2 H 3 NaO 2 0.25 mol

 _____ g C 2 H 3 NaO 2 in _____ mL vol. flask
mol
1000 mL
□ 50 mL of 0.25 M NH3 (ammonia)
- dilute solution from 15.0 M (28%) ammonia in DI water and store in a clear or brown glass bottle
_____ groups 
50 mL 0.25 M NH 3
 _____ mL total of 0.25 M NH 3 solution
group
2
- please round volume of 0.25 M NH3 needed to match the nearest volumetric flask volume available
(i.e. to the nearest 500 mL or 1 L). Amount of 0.25 M NH3 to prepare: _____ mL
_____ mL vol. flask 
0.25 M NH3
 _____ mL 14.8 M NH3 for dilution in _____ mL vol. flask
15.0 M NH3
□ 60 mL of 0.25 M NH4Cl (ammonium chloride)
- prepare solution from the solid (FW 53.49 g) and dilute in DI water and store in a clear or brown
glass bottle
_____ groups 
60 mL 0.25 M NH 4 Cl
 _____ mL total of 0.25 M NH 4 Cl solution
group
-please round volume of 0.25 M NH4Cl needed to match the nearest volumetric flask volume
available (i.e. to the nearest 500 mL or 1L). Amount of 0.25 M NH4Cl to prepare: _____ mL
_____ mL vol. flask 
53.49 g NH 4 Cl 0.25 mol

 _____ g NH 4 Cl in _____ mL vol. flask
mol
1000 mL
□ 60 mL of 0.25 M Histidine
- prepare solution from the solid (FW 155.15 g) and dilute in DI water and store in a clear or brown
glass bottle
_____ groups 
60 mL 0.25 M histidine
 _____ mL total of 0.25 M histidine solution
group
-please round volume of 0.25 M histidine needed to match the nearest volumetric flask volume
available (i.e. to the nearest 500 mL or 1L). Amount of 0.25 M histidine to prepare: ______mL
_____ mL vol. flask 
155.15 g histidine 0.25 mol

 _____ g histidine in _____ mL vol. flask
mol
1000 mL
□ 60 mL of 0.25 M Histidine HCl
- prepare solution from solid Histidine HCl  H2O (FW 209.63 g) and dilute in DI water and store in a
clear glass bottle
_____ groups 
60 mL 0.25 M histidine HCl
 _____ mL total of 0.25 M histidine HCl solution
group
3
-please round volume of 0.25 M histidine HCl needed to match the nearest volumetric flask volume
available (i.e. to the nearest 500 mL or 1L). Amount of 0.25 M histidine HCl  H2O to prepare: ____
mL
_____ mL vol. flask 
209.63 g histidine HCl  H 2 O 0.25 mol

 _____ g histidine HCl in _____ mL vol. flask
mol
1000 mL
EQUIPMENT & GLASSWARE
For Soap Scum In Lab Bins:
For Soap Scum In Dana 201:
□ 10 mL volumetric flask (1)
□ fat test tubes (5)
□ fat test tube racks, 4-way plastic (2)
□ 1000 μL micropipette (1)
□ 400 mL beaker (1) (for waste)
□ In hoods everything except HCl & NaOH each
on own safety tray with labeled 30 mL beaker
□ Milli-Q H2O
□ pH meter & instruction sheet (1/group)
□ pH 4 and 7 buffers in labeled vials next to
each pH meter (1/group)
□ 1000 μL pipet tips
For Soap Scum In Lab Bins:
□ 30 or 50 mL beakers (2)
Additional For Goldfish In Dana 201:
□ buret and small waste beaker for each
chemical from 1st week, labeled
□ HCl & NaOH on separate trays
□ burets and beakers for Milli-Q H2O (2)
WASTE DISPOSAL CONTAINERS
 Building: Dana
 Room #: 201
 Waste Accumulation Start Date: 10/24/2013
 Date Container Filled: leave blank
 Date moved to MAA: leave blank
 Physical State(s): liquid
 Chemical Waste Composition: hydrochloric acid (< 1%), sodium hydroxide (< 1%), ammonia (< 1%),
ammonium chloride (< 1%), acetic acid (< 1%), sodium acetate (< 1%), histidine (< 1%), histidine HCl
monohydrate (< 1%), water (~ 99%)
 Hazards: toxic, corrosive
SPECIAL INSTRUCTIONS
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