Question

data handling, recording, and analysis & lab safety
percent error, significant figures, precision & accuracy, temperature, volume
when reading the volume of a liquid in a graduated cylinder,
read at the middle of the meniscus.

1. what is the volume of the liquid in the

graduated cylinder?
a. 46 ml
b. 40 ml
c. 46.0 ml
d. 45.0 ml

1. true or false: it is okay to pick up broken glass with your

bare hands if the glass is placed in the trash can.
a. true
b. false

1. the proper way to heat a substance in a test

tube is to __.
a. point it away from people
b. move the test tube in the flame for even
heating
c. hold the test tube with a test tube holder
d. all the above should be done when heating
the contents of a test tube.

1. which footwear is not acceptable to wear

during a lab or hazardous setting?
a. boots (not furry ones)
b. tennis shoes
c. steel - toed shoes
d. sandals

1. after completing an experiment, all

chemical waste should be __.
a. dumped down a sink
b. consumed
c. thrown in the trash
d. disposed of according to teacher’s
directions

Explanation:

1. For a graduated cylinder, read the bottom of the meniscus. The cylinder has 1 mL increments, so the volume is 46.0 mL (with proper significant figures).
2. Broken glass can cut skin, so never pick it up with bare hands, even to discard.
3. When heating a test tube, point it away from people to avoid injury from splashes, move it for even heating, and hold it with a test tube holder. All these steps are correct.
4. Sandals expose feet to potential chemical spills or broken glass, so they are not acceptable lab footwear.
5. Chemical waste must be disposed of properly per instructions to avoid hazards; dumping or throwing in regular trash is unsafe.

Answer:

1. C. 46.0 mL
2. B. false
3. D. All the above should be done when heating the contents of a test tube.
4. D. sandals
5. D. disposed of according to teacher's directions