How To Solve a Word Problem in Chemistry

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How To Solve a Word Problem in Chemistry
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Step 1.

• Take a deep breath and relax.

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Step 2.

• Determine and mark what is asked for in your
  problem make sure to include units.
• A piece of copper is placed in a graduated
  cylinder containing some water. The total volume
  of the water increases by 7.43 mL. What is the
  mass of the piece of copper in grams (density
  8.92 g/cm3)?
• Question What is the mass of the piece of
  copper (g)?

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Step 3.

• Identify and write down all givens and units
  given in the problem.
• A piece of copper is placed in a graduated
  cylinder containing some water. The total volume
  of the water increases by 7.43 mL. What is the
  mass of the piece of copper in grams (density
  8.92 g/cm3)?
• Question What is the mass of the piece of
  copper?
• Givens 1) Total water volume increases
  7.43 mL
• 2) Density of Copper 8.92 g/ cm3

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Step 4.

• Write down the Givens for the problem.
• A piece of copper is placed in a graduated
  cylinder containing some water. The total volume
  of the water increases by 7.43 mL. What is the
  mass of the piece of copper in grams (density
  8.92 g/cm3)?
• Question What is the mass of the piece of
  copper?
• Givens 1) Total water volume increases
  7.43 mL
• 2) Density of Copper 8.92 g/cm3

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Step 5.

• Find the equation necessary to solve the problem.
• A piece of copper is placed in a graduated
  cylinder containing some water. The total volume
  of the water increases by 7.43 mL. What is the
  mass of the piece of copper in grams (density
  8.92 g/cm3)?
• Question What is the mass of the piece of
  copper?
• Givens 1) Total water volume increases
  7.43 mL
• 2) Density of Copper 8.92 g/cm3
• Equation 1) Density (g/cm3) Volume (mL)
  Mass (g)

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Step 6.

• Check All Units
• Equation 1) Density (g/cm3) Volume (mL)
  Mass (g)
• Unit Check 1) cm3 is not the same unit as mL.
• Conversion 1) 1 mL 1 cm3 7.43 mL 7.43 cm3

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Step 7.

• Put the variables in and solve the equation.
• Solution 8.92 (g/cm3) 7.43 (cm3) Mass (g)
• Answer Mass (g) 66.3 (g)

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Step 8.

• Recheck to determine if the units are the same
  as the problem and the answer seems reasonable.
• Recheck of units Desired unit (gram) Answer
  (grams)

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• A piece of copper is placed in a graduated
  cylinder containing some water. The total volume
  of the water increases by 7.43 mL. What is the
  mass of the piece of copper in grams (density
  8.92 g/cm3)?
• Question What is the mass of the piece of
  copper?
• Givens 1) Total water volume increases
  7.43 mL
• 2) Density of Copper 8.92 g/cm3
• Equation 1) Density (g/cm3) Volume (mL)
  Mass (g)
• Unit Check 1) cm3 is not the same unit as
  mL.
• Conversion 1) 1 mL 1 cm3 7.43 mL 7.43
  cm3
• Solution 1) 8.92 (g/cm3) 7.43 (cm3)
  Mass (g)
• Answer Mass (g) 66.3 (g)
• Recheck of units Desired unit (gram) Answer
  (grams)