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Calculate the molarity of the solutions described below. Round all answers to 2 decimal places. Hint: Use molar mass and dimensional analysis to convert grams into moles. A) 100.0 g of sodium chloride is dissolved in 3.0 L of solution. Answer: 0.57 M B) 72.5 g of sugar (C12H22O11) s dissolved in 1.5 L of solution. Answer: 0.13 M C) 125 g of aluminum sulfate is dissolved in 0.150 L of solution. Answer: M D) 1.75 g of caffeine (C8H10N4O2) is dissolved in 0.200 L of solution. Answer: M

User Mindthief
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2 Answers

3 votes

Answer:

Hi and sorry.

But what is the question in that?

There is already answers so i don't know how to help you.

Step-by-step explanation:

User Nora
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6 votes

Step-by-step explanation:

A) To calculate the molarity of sodium chloride solution, we need to first convert the mass of sodium chloride into moles, using its molar mass of 58.44 g/mol:

100.0 g NaCl × (1 mol NaCl/58.44 g NaCl) = 1.71 mol NaCl

Then, we divide the number of moles by the volume of solution in liters to get the molarity:

Molarity = 1.71 mol NaCl ÷ 3.0 L = 0.57 M

Therefore, the molarity of the sodium chloride solution is 0.57 M.

B) To calculate the molarity of sugar (C12H22O11) solution, we need to first convert the mass of sugar into moles, using its molar mass of 342.3 g/mol:

72.5 g C12H22O11 × (1 mol C12H22O11/342.3 g C12H22O11) = 0.212 mol C12H22O11

Then, we divide the number of moles by the volume of solution in liters to get the molarity:

Molarity = 0.212 mol C12H22O11 ÷ 1.5 L = 0.13 M

Therefore, the molarity of the sugar solution is 0.13 M.

C) To calculate the molarity of aluminum sulfate solution, we need to first convert the mass of aluminum sulfate into moles, using its molar mass of 342.2 g/mol:

125 g Al2(SO4)3 × (1 mol Al2(SO4)3/342.2 g Al2(SO4)3) = 0.365 mol Al2(SO4)3

Then, we divide the number of moles by the volume of solution in liters to get the molarity:

Molarity = 0.365 mol Al2(SO4)3 ÷ 0.150 L = 2.43 M

Therefore, the molarity of the aluminum sulfate solution is 2.43 M.

D) To calculate the molarity of caffeine (C8H10N4O2) solution, we need to first convert the mass of caffeine into moles, using its molar mass of 194.2 g/mol:

1.75 g C8H10N4O2 × (1 mol C8H10N4O2/194.2 g C8H10N4O2) = 0.009 mol C8H10N4O2

Then, we divide the number of moles by the volume of solution in liters to get the molarity:

Molarity = 0.009 mol C8H10N4O2 ÷ 0.200 L = 0.045 M

Therefore, the molarity of the caffeine solution is 0.045 M

User Deanvmc
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