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A venti latte (502mL) contains 0.322g caffeine, C8H10N4O2, express this concentration in molarity.

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Answer:

0.00331M

Step-by-step explanation:

Molarity of a solution can be calculated as follows:

Molarity = number of moles (n) ÷ volume (V)

In the information provided in this question, the volume = 502mL = 502/1000 = 0.502L, mass of caffeine = 0.322g

Molar mass of caffeine (C8H10N4O2), where C = 12, H = 1, N = 14, O = 16 is as follows:

Molar mass = 12(8) + 1(10) + 14(4) + 16(2)

= 96 + 10 + 56 + 32

= 194g/mol

Using, moles = mass/molar mass

moles = 0.322/194

moles = 1.66 × 10-³ moles

mole = 0.00166mol

Molarity = number of moles ÷ volume

Molarity = 0.00166mol ÷ 0.502L

Molarity = 0.00331M.

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