PBS CFA: Unit 1: The Mystery

A short unit check. Enter your Student ID and answer each item. This is practice, not a grade.

1. 1. An SDS (Safety Data Sheet) for a chemical tells you all of the following EXCEPT:

   AIts physical and health hazardsBFirst-aid steps after exposureCThe PPE needed to handle itDIts resale price

2. 2. The SDS for a reagent warns that it causes serious eye damage. Before you pour it, you put on:

   AGloves, and keep your face backBGloves and splash gogglesCGloves and safety glasses with open sidesDA lab coat and a face shield

3. 3. "The victim has a bruise on the left arm" is an observation. "The victim was grabbed" is:

   AAn inferenceBAn observationCA measurementDA prediction

4. 4. A bloodstained shirt at a scene is still damp. Before it is packaged, it should be:

   ASealed wet inside a plastic evidence bagBLeft at the scene until the stain driesCRinsed clean of dirt and then baggedDAir dried, then packaged in a paper bag

5. 5. A swab from a scene is sealed inside an evidence container. The container should be labeled:

   AWhen it is signed into the evidence lockerBAt the lab, from your scene notesCAt the scene, before you set it downDAfter the case number is assigned

6. 6. Benedict's solution turns orange with a sample. This indicates the presence of:

   AA reducing sugar like glucoseBA lipid like vegetable oilCStarch, a complex carbohydrateDA protein like albumin

7. 7. You test four unknown powders with iodine. What keeps one sample from affecting the next?

   ATest the samples in alphabetical orderBUse one dropper and wipe it on a towelCUse a clean dropper for each sampleDAdd extra iodine to the later samples

8. 8. Alveoli in the lungs are tiny and numerous. This structure supports their function by:

   AMaximizing surface area for gas exchangeBWarming and moistening incoming airCFiltering dust and germs out of the airDStoring a reserve of oxygen for later

9. 9. A single witness saw the event from far away at night. Their account is:

   AStrong enough to identify a suspectBPhysical evidence of what happenedCUseful but limited in reliabilityDToo weak to include in the report

Enter your Student ID to submit.