AChem Chapter 1-2 Formative Assessment Answers

1. Measurement

  • 0.185m
  • 0.240m
  • 0.300m

2. Metric Prefixes

  • mega: M, meaning: E9
  • nano: n, meaning: E-9
  • pico: p, meaning: E-12
  • milli: m, meaning: E-3
  • centi: c, meaning: E-2

3. Conversions

  • 5.467E-5hm
  • 3.77E8mg
  • 7.45E6cL
  • 1.253763E-9km

4. Sci. Notation

  • 6.82410230E-1
  • 1.26537872E7
  • 3.32E3
  • 3.4E-6

5. Math with Sci. Notation

  • 6.06E23
  • 2.53E1

6. Counting Significant Digits

  • 8.3007 g–> 5SF
  • 9.0000 mL –> 5SF
  • 0.0000001s –> 1SF
  • 572 pencils –> 3

7. Math with Significant Digits

  • 100 (ones place)
  • 8.0E2 (2SF)

8. observation (5 senses) –> problem statement (form of question) –> write hypothesis (if, then, b/c) –> design experiment (IV, DV, constants, control) –> Perform experiment/Collect Data –> Analyze data (graphs) –> Draw conclusions (refer back to hypothesis, use data to support/reject, analyze reliability and validity of data)

9.

  • no, yes
  • yes, yes
  • no, no

9.

  • Group 1- accurate (b/c….compare actual values to standard)
  • Group 2- precise (b/c…compare actual values to each other…find biggest difference)

10.

  • Given: 6.28 moles
  • Find: atoms
  • Conversion Factor: 1mol/6.022E23atoms
  • Answer: 3.78E24atoms