In the world of hazmat response we are mainly concerned about those extreme ends 0-2 ph and the 11-14 ph. Especially if it is in a gas/vapor phase! If we can get the responders to remember RED and BLUE we are normally good. That signals to them the acid or base. But there is much more to it of course. Some of these demos are simple and lead into other discussions.

First Demo

Concepts:

Acids, bases, sulfates, nitrates, halogens, ammonia, hydroxides

Safety:

Safety glasses MUST be worn at all times by demonstrator and the audience

Nitrile gloves

Equipment:

• General ph indicator

• Dry ice

• Graduated cylinder (Plastic )

• Tongs

Preparation:

1. Add water to a graduated cylinder

2. Add the general ph indicator to the water and mix, should be a green color.

3. Stage the dry ice next to the graduated cylinder

Demonstration Instructions

1. Take the ph of the green solutions should be neutral, remember some of the color may alter the ph paper if too concentrated.

2. Carefully drop a piece of dry ice into the dyed solution and you will see color changes from green, yellow to orange red.

Observations:

• Color changes from green, yellow to orange red.

• H2O + CO2 = H2CO3, carbonic acid

Learning Outcomes:

• This leads into discussion of liquid CO2 responses at restaurants and convince stores. Just about every store that has a soda machine has a Dewar of CO2.

• You can talk about neutralizing acids and bases.

• This can lead into strong acids like HCL and weak acids like HF. OR skin peelers like sodium hydroxide at ph 14.

• Ammonia has a specific ph at 11.

• Halogens, sulfates and nitrates tend to make acids. Such as sulfuric acid, nitric acid, HF, HCL, HI, HBR ect..

• Ph 14 are always hydroxides. It does not matter if its sodium hydroxide or potassium hydroxide it will still peel your skin off better than acids. They dissolve the fat in your skin. Here is a better definition from the web; Saponification is the process in which triglycerides are combined with a strong base to form fatty acid metal salts during the soap-making process.

Chemical Disposal:

The dye and carbonic acid are not hazardous.

Additional Information

2-Second Demo

Concepts:

FUN

Safety:

Safety glasses MUST be worn at all times by demonstrator and the audience

Lab coat

Equipment:

• Disappearing ink

• Carbon dioxide fire extinguisher

Preparation:

No prep but need a volunteer

Demonstration Instructions

1. Have the unsuspecting volunteer put on the lab coat and safety glasses

2. Then put the disappearing ink on the lab coat (If left alone it will disappear with the CO2 in the air ~400 ppm)

3. But you can speed up the process by blasting the CO2 fire extinguisher on the lab coat, not too close!

Observations:

• The ink disappears

Learning Outcomes

• Neutralizing acid and bases

Disposal Information

The dye and carbonic acid are not hazardous.

Additional Information

Don't freeze your volunteer!

3 - Third Demo

Concepts:

More ph

Safety:

Safety glasses MUST be worn at all times by demonstrator and the audience

Nitrile gloves

Equipment:

• Windex

• Golden rod paper https://www.teachersource.com/product/color-changing-goldenrod-paper?gclid=Cj0KCQjwlK-WBhDjARIsAO2sErRRg3KVnLFHy-kc71sARCD3j3XuiPCGrD-PkcCuxstJFYMwtLB-8gUaAqhkEALw_wcB

• Amazon https://www.amazon.com/100-PACK-of-Goldenrod-Paper/dp/B00QUBKIL4

Preparation:

none

Demonstration Instructions

• Spray windex on your gloved hand or use baking soda and water

Observations:

• "Bloody" hand print

Learning Outcomes:

• True goldenrod paper is made from a dye which is an acid-base indicator. This paper turns bright red in bases such as ammonia, baking soda or washing soda and returns to bright yellow in acids such as vinegar or lemon juice.

Chemical Disposal:

None

Additional Information:

Come up with a fun story before you start. Maybe the importance of wearing gloves!