Chapter 4 Problem Solving in Chemistry REVIEW

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Chapter 4Problem Solving in ChemistryREVIEW

• Charles Page High School
• Dr. Stephen L. Cotton

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Chapter 4 - Review

• The best way to become a better problem solver is
  by
• What step is at the heart of problem solving?
• What is the volume of 60.0 g of ether if the
  density is 0.70 g/mL?
• How are the numerator and denominator in a
  conversion factor related?

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Chapter 4 - Review

• How many significant figures are there in the
  conversion factor of 100 cm / 1 m?
• If the correct conversion factor is 100 cm / 1 m,
  and the known measurement is 25 m, what is the
  answer given by dimensional analysis?

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Chapter 4 - Review

• If the correct conversion factor is 1 L / 1000
  mL, and the known measurement is 33 mL, what is
  the answer given by dimensional analysis?
• What is the volume 1 x 104 L expressed in cubic
  centimeters?
• How many cm are in 3 km?

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Chapter 4 - Review

• How many miles does light travel in 1 microsecond
  in a vacuum, if the speed of light in a vacuum is
  186 000 miles/sec?
• What conversion factor would you use to change 1
  x 104 L into cubic centimeters?
• Change 31 kg into nanograms.

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Chapter 4 - Review

• Change 197 ?g into kilometers.
• What is the result of converting 0.256 ?L to
  kiloliters?
• Change 0.04 kmol to centimoles.
• What is the result of converting 794 dg to
  centigrams?
• Change 631 mm to m.

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Chapter 4 - Review

• Word problems normally deal with relationships
  between what type of quantities?
• Which is a correct conversion factor 100 L /
  1000 mL, or 100 L / 1000 dL
• Which can be converted into grams pounds, or
  liters

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Chapter 4 - Review

• Which is a correct conversion factor 0.01 g / 1
  cg, or 0.01 L / 1 cm?
• Which is a correct conversion factor 1000 m / 1
  km, or 1000 km / 1 m?
• Which if a correct conversion factor 1000 g / 1
  ?g, or 1 000 000 ?g / 1 g?
• What is the value of the conversion factor 1 mg /
  0.001 g?

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Chapter 4 - Review

• A conversion factor
• What step of problem solving is aided by
  dimensional analysis?
• Dimensional analysis involves multiplying a
• What conversion factor would be used to change
  kilograms to grams?
• To change liters to centiliters?

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Chapter 4 - Review

• Which conversion factor(s) would change cm to km?
• What conversion factor(s) would change kmol to
  nanomoles?
• The density of aluminum is 2.70 g/cm3. What is
  the mass of a cube of aluminum 1.0 cm on each
  edge?

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Chapter 4 - Review

• What is the result of converting 48 m to
  centimeters?
• What is the result of converting 63 mL to liters?
• Five kilometers is equal to how many centimeters?

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Chapter 4 - Review

• If 20 gits 1 erb, and 1 futz 2 hews, and 10
  erbs 1 futz, how many gits equal 5 hews?
• Express the density 5.6 g/cm3 in kg/m3.
• How would the rate 60 m/s be expressed in km/hr?

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Chapter 4 - Review

• How would the ratio 18 g/mol be expressed in
  kilograms per kilomole?
• What approach is often used when trying to plan a
  solution to a complex problem?
• What conversion factor(s) would calculate the
  seconds in an 8-hour work day?

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Chapter 4 - Review

• The diameter of a sodium atom is 3.7 nanometers.
  What conversion factor(s) would be used to
  express this measurement in centimeters?

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Chapter 4 - Review

• A blacksmith has to put new shoes on a stable of
  20 horses. Each shoe requires 3 nails. How can
  he/she calculate the number of nails that must be
  brought to the stable?