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Concentration Terms and Calculations - Quantum

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Solution:Write down the given values with theirunits <strong>and</strong> what they represent.In this problem, molarity is given for the solute ethyleneglycol <strong>and</strong> the solvent water. The chemical formula forethylene glycol is C 2 H 6 O 2 . The molar masses of C, H, <strong>and</strong> Ocan be obtained from the Periodic Table.mg/v% = 100. mg glucose/100. mL blood1 mol C = 12.01 g/mol1 mol O = 16.00 g/mol1 mol H = 1.008 g/molmolar mass ethylene glycol = 62.07 g/molWrite down the unknown <strong>and</strong> its unit.The m/v% of ethylene glycol in antifreeze is unknown.m/v% ethylene glycol = ?Develop a strategy to solve the problem.The definition of m/v% isA dimensional analysis problem is set up to give gC 2 H 6 O 2 /100 mL antifreeze.Round off the answer to the correctnumber of significant digits <strong>and</strong> give theappropriate units.The molarity has 3 significant digits while the molar masshas 4. The m/v% is rounded off to 3 significant digits. Theanswer ism/v% = 52.4 m/v% ethylene glycolCheck whether the answer is reasonable.The moles of C 2 H 6 O 2 in 100 mL is 0.1 that in a liter. Themass of C 2 H 6 O 2 in 100 mL antifreeze is 0.8 its molar mass;the answer is reasonable.

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