On The Subject Of Stoichiometry

Bless You?

Oh no! Someone has accidentally mixed up the acids you were working with! Now it’s your job to successfully titrate with the correct bases before the acids can burn through your table.

This module is disarmed by successfully neutralizing both acids at the same time. In order to solve this module, you must deduce the types of bases you need and how much you need in grams. Additionally, you need to figure out what salts you will end up with and if the resulting combination will produce a gas. Watch out though, some of those gases can be toxic.

To control the module, use the following:

1. The two white buttons on the left of the top display traverse the list of bases and salts.
2. The indicator button (to the right of the top display) switches between the two bases and the two salts that are being submitted. The blue text indicates one of the base/salt pairs to be submitted, the red text indicates the other. Whichever is currently displayed will be the one submitted when clicking Titrate.
3. The black base/salt button above the reaction vessel switches between bases and salts.
4. For each vent, there is a green vent button and a red filter button that toggle the vents and toxicity filter respectively.
5. Once the appropriate conditions are set, press “Titrate” to confirm the solution.

An incorrect input yields a strike. The correct answer will not change. Useful information may be found in Appendix: CH3M15TRY.

Identifying the Acids

For the first acid, follow the flow chart normally; for the second acid, follow the flow chart, but invert the answer to each question. e.g. Yes becomes No

* = Triflic Acid is often represented as HOTf, where Tf is triflate, CF₃SO₃^-.

However!

If you have exactly two batteries in one holder, and a lit FRK indicator, then you have AzidoAzideAzide (AAA for short). This is the most explosive compound man has ever created. Lucky for you, we here at the KTaNE Lab have protocols in place for this. Leave it alone and refer to your flow chart. Go through it once to get what your acid would have been. Calculate the molar mass of one mole of that acid, truncate, and then click submit when the two seconds digits of the timer are equal to that number. If the number is sixty or higher, then take the digital root and submit when the seconds digits are equal to that number. Remember to prepend a zero if you need one!

Determining the Bases for Neutralization

On the module, the two acids have flowed into one beaker and are now emitting a single color. Based on this color, refer to Table 2 to find the correct two bases to make that color white.

If the color shown on the module is a primary color (RGB), then the other two primary colors must be chosen. If the color shown on the module is a secondary color, then the other two secondary colors must be chosen. Finally, if the color on the module is black or white, then black and white must be used.

If there is an indicator with a matching letter in the phrase GET A LAB COAT, then the higher color in the table is used for the first acid, and the lower is used for the second acid. Otherwise, use the lower color for the first acid, and the higher for the second.

Finding The Acid Amounts:

In order to titrate successfully, you need to figure out how much of each acid your boss ordered. You can do this with the molar mass of each compound. The molar mass of a compound, typically given in units of grams per mole (g/mol), is determined by summing the molar masses of each of its constituent elements (which can be found at the bottom of an element’s square on the Periodic Table), with each elemental molar mass multiplied by the number of atoms of that element in its formula.

Additionally, your boss is a tad erratic and experimental in his methods. He asked you to use different amounts of acid based on what day of the week it is. Multiply the normal amount by that day’s requested amount to find the actual acid amount. For reference, the normal amount of the first acid is 16 grams and the second acid is 20 grams.

Simple Sunday:

He wanted to keep things simple and ordered half the normal amount of acid.

Madness Monday:

He caught a crazy hair and ordered one and a half times the normal amount.

Terrible Tuesday:

He was feeling particularly mean and ordered seven-fifths the normal amount.

Wonderful Wednesday:

He was feeling generous and decided to order forty-twentieths the normal amount of acid.

Thoughtful Thursday:

He wanted to challenge your mind and ordered nine-quarters the normal amount of acid.

Fabulous Friday:

He was feeling lazy and giving, so he just ordered the normal amount.

Superstitious Saturday:

He is a madlad and got you thirteen-sixteenths the normal amount.

The amount of a substance in moles is determined by dividing the mass of the substance by its molar mass. Therefore, divide the grams of your day’s amount by the molar mass of the acid. Leave all rounding until the final answer.

Finding The Base Amounts

Now that you have the amount of the acids, you can determine the amount of base required to properly neutralize the mixture. The molar mass of a base can be determined by the same method as was used for calculating the molar mass of an acid.

To determine the amount of base required to neutralize the acid mixture, first take the amount of the first acid in moles. Then determine the molar ratio X/Y for the mixing of your first acid and base (i.e. X moles of base is required to neutralize Y moles of acid). X is equal to the magnitude of the charge on the anion of the acid, and Y is equal to the magnitude of the charge on the cation of the base.
e.g. Acid H₂SO₄: X = 2 from SO₄^2-, Base NaOH: Y = 1 from Na⁺

Multiply your moles of acid by the molar ratio to convert to moles of base, subsequently converting your base back to grams by multiplying by its molar mass. Then, round your answer up to the nearest integer, and set this two-digit number as the input for your first base. If the final number of grams is greater than 99, enter 99.

Then, repeat this process for your second acid/base reaction.

Finding The Salts And Gases:

Finally, you must log the correct salts that will result from the titration combinations, and figure out if you need to turn the gas filter and/or toxicity filter on. The correct salt for each reaction will be composed of both the anion of the acid and the cation of the base. The gases and filter states can be found using Appendix: CH3M15TRY.

Abating The Danger:

To abate the danger, select either base to be submitted and toggle to the salt list. The base you selected will stay selected. Scroll to the appropriate salt and leave it there. Next, enter in the grams amount and set the appropriate air/toxicity filter states on the left side, then press Titrate. Repeat this process for the second base/salt pair and the right side air/toxicity filter and press Titrate.

Congratulations! You stopped the formation of a new Superacid! Your boss is so proud! There might be a promotion in your future!
See you next time!

Appendix: CH3M15TRY

Note: In accordance with Department of Environmental Health and Safety guidelines, you MUST filter out toxic vapors, to protect the general public from your actions. If ventilation is required, press the green vent button. If the toxicity filter is required, press both the red filter button and the vent button.

V

= Ventilation On

T

= Toxicity Filter On