Question

part 2: details of chemical, heating and fire safety, safety equipment, and accidents/first aid
directions:

1. read through the “chemical, heating, and fire safety” rules and the “lab safety equipment” sheet.
2. answer the questions below. make sure all members of your group share the same answers.
3. describe the proper way of detecting the odor of a chemical substance. what is this technique called?
4. the university of california, berkeley’s department of environmental health and safety notes that “heat is released when strong acids are mixed with water. if you add water to acid, you form an extremely concentrated solution of acid and the solution may boil very violently, splashing concentrated acid. if you add acid to water, the solution that forms is dilute and the small amount of heat released is not enough to vaporize and spatter it.” when mixing strong acids, is it safer to add acid to water, or to add water to acid? explain your response in your own words.
5. how do you dispose of your chemical wastes at the end of a lab?
6. why is it against the chemical safety rules to return unused chemicals to their containers?
7. how do you determine if heated glassware is safe to touch?
8. what “dress code” rules should be obeyed when using an open flame?
9. how will you exit the room in case of fire?

what should you do if there is a fire on some materials at your lab station?

Explanation:

1. To detect the odor of a chemical substance, you waft the air towards your nose gently with your hand. This technique is called wafting. It helps avoid inhaling a large quantity of potentially harmful fumes at once.
2. It is safer to add acid to water. When acid is added to water, the heat released is dissipated in the large - volume water, preventing violent boiling and splashing. If water is added to acid, the heat can cause the water to boil violently and splash concentrated acid.
3. Chemical wastes should be disposed of according to the specific instructions of the lab. Usually, they are collected in designated waste containers labeled for the type of chemical waste (e.g., acid waste, organic waste).
4. Returning unused chemicals to their containers can contaminate the entire stock of the chemical. Once a chemical has been taken out of its container, it may have been exposed to contaminants or undergone a chemical change, so it should not be put back.
5. To determine if heated glassware is safe to touch, you can hold your hand close to it (without touching) to feel for residual heat. Another way is to wait for a sufficient amount of time based on the type of glassware and the heat source used.
6. When using an open flame, the "dress code" rules include wearing long - sleeved, non - flammable clothing, tying back long hair, and removing loose jewelry to prevent them from catching fire.
7. In case of a fire, you should follow the pre - established evacuation route. Do not use elevators; use the stairs instead. Alert others in the area and proceed calmly to the designated assembly point outside. If there is a fire at your lab station, use the appropriate fire - fighting equipment (such as a fire extinguisher if trained to do so) or smother the fire with a fire blanket if it is small.

Answer:

1. Waft the air towards your nose gently with your hand. Wafting.
2. Add acid to water. When acid is added to water, heat is dissipated safely; adding water to acid can cause violent boiling and acid splashing.
3. Dispose according to lab - specific instructions, usually in designated waste containers.
4. Can contaminate the entire stock of the chemical as it may have been exposed to contaminants or changed chemically.
5. Hold your hand close to it (without touching) to feel for heat or wait for an appropriate amount of time.
6. Wear long - sleeved, non - flammable clothing, tie back long hair, and remove loose jewelry.
7. Follow the pre - established evacuation route, use stairs, alert others, and go to the assembly point. If at lab station, use fire extinguisher (if trained) or fire blanket.