Review words of Unit I. Find 15 words in the puzzle.

UNIT II. LABORATORY.

1. Discuss the following questions:

1. Is a chemical laboratory a dangerous place? Why?

2. What should you know before you go to a laboratory?

Match the following names of laboratory equipment to the pictures. What are their Russian equivalents?

Analytical balance; dropper; condenser; funnel; beaker; petri dish; volumetric flask; Erlenmeyer flask; tongs; burette; Buchner funnel; Florence (boiling) flask; evaporating dish; watch glass; 24-well plate; crucible; Buchner flask; mortar and pestle; test tube; wash bottle; graduated cylinder; iron ring; utility clamp; safety goggles; gas bottle; test tube rack; ring stand; thermometer; Bunsen burner; pipette.

Read the following descriptions of laboratory equipment. Fill in the gaps with the names of proper items.

1. _________ are flat-bottom cylinders with a spout at the top. They have one or several measurement lines and are used to measure volumes with a decent level of accuracy.

2. The ____________ is named for the chemist who invented it. It is conical, with a flat bottom. Like beakers, they are good for rough volume measurements. The shape of the flask helps prevent splashes and spills.

3. A _________ is intended to measure a specific volume with a high level of accuracy. Typical sizes include 100-ml and 250-ml. Because they are precision glassware, they are expensive to replace. Handle with care!

4. A ________ is used to dispense a specific volume of liquid. There are typically volume markings along the side and a stopcock to control flow.

5. _______ are used in microbiology labs because the cover fits loosely enough to allow gas exchange, but discourages contamination.

6. A ______ is handy when you want a more accurate volume measurement than you would get from a beaker or Erlenmeyer. The cylindrical shape that makes them easy to read also makes them easy to knock over and break.

7. ________ are wide at the top and narrow at the base. Their goal in life is to keep you from spilling stuff all over the counter, thus making a mess and losing your sample. This item is found in most homes, not just the lab.

8. A ________ is a hollow piece of glassware that allows a coolant (usually water) to flow and "condense" a vapor into a liquid.

9. A _______ has a round bottom and a long enough neck that you can attach a clamp around it to hold it over a flame. It's typically made of heat-resistant glass.