A student must heat the contents of a test tube. Which of the following shows the correct technique to use to heat and hold the test tube?

• A
• B
• C
• D

Of the following symbols, which represents a biological hazard?

• A
• B
• C
• D

Students will conduct an experiment using the following materials: bunsen burner, beaker of water, glass tubing, four test tubes containing different chemicals, and rubber stoppers. Which of these steps is MOSTcritical for students to follow when using these materials in the lab?

• Wearing eye protection at all times
• writing the lab procedure in a notebook
• washing hands before starting the experiment
• placing a stopper on all test tubes before heating them 

While heating a test tube it is important to _

• make sure the liquid level is at the top of the test tube
• make sure the test tube is pointing away from people
• keep the test tube perfectly still while it is being heated
• heat the bottom tip of the test tube

Two safety features found in most laboratories are a safety shower and a safety fountain with two water jets. What is the main purpose of the safety fountain?

• to irrigate nostrils is fumes are inhaled
• to rinse mouth if chemicals are ingested
• to wash hands if exposed to toxic material
• to flush the eyes if contaminated with chemicals

While working on a class chemistry experiment, Victor dropped a glass test tube filled with an unknown liquid. What should Victor do first?

• put on gloves
• inform the teacher
• sweep up the broken glass
• clean up the spilled chemical 

Metals and nonmetals generally form ionic bonds with each other. Which of the following sets of elements will MOST LIKELY form an ionic bond?

• Na, F
• Cl, F
• Na, K
• He, O

Which of the following is an important action to follow when heating a test tube?

• plug the mouth of the tube with a cork 
• point the mouth of the tube away from everyone
• hold the test tube steady in the hottest part of the flame
• grasp the rim of the test tube with tongs

When working in a laboratory, which one of the following actions does NOT represent safe and correct chemical handling?

• Pouring chemical waste down the drain
• Cleaning up chemical spills immediately
• Washing hands after handling chemicals
• Keeping noxious or dangerous chemicals under fume hoods

Students are conducting an experiment to determine if sugars are present in foods. They heat a test tube containing a sugar solution in a beaker of water. Which of these is an unsafe laboratory practice in this experiment?

• heating the sugar solution in a closed test tube
• rinsing hands with water after handling the materials
• using a test tube clamp to hold the test tube
• wearing safety goggles while heating the sugar solution