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olga nikolaevna [1]
3 years ago
10

Vanillin (used to flavor vanilla ice cream and other foods) is the substance whose aroma the human nose detects in the smallest

amount. The threshold limit is 2.0 x 10^-11 g per liter of air. If the current price of 50 g of vanillin is $112, determine the cost to supply enough vanillin so that the aroma could be detected in a large aircraft hangar with a volume of 5.0 x 10^7 ft^3.
Chemistry
1 answer:
balu736 [363]3 years ago
5 0

Answer:

Cost to supply enough vanillin is 3.2\$

Explanation:

Threshold limit of vanillin in air is 2.0\times 10^{-11}g per litre means there should be 2.0\times 10^{-11}g of vanillin in 1L of air to detect aroma of vanillin.

1ft^{3}=28.32L

So, 5.0\times 10^{7}ft^{3}=(5.0\times 10^{7}\times 28.32)L

So amount of vanillin should be present to detect = (2.0\times 10^{-11}\times 5.0\times 10^{7}\times 28.32)g

As cost of 50 g vanillin is 112\$ therefore cost of  (2.0\times 10^{-11}\times 5.0\times 10^{7}\times 28.32)gvanillin = (2.0\times 10^{-11}\times 5.0\times 10^{7}\times 28.32\times 112)\$ = 3.2\$

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Answer:

Explanation:

1) Acetic acid

Concentration is given as 0.103 M

The average pH of this solution = 2.96

we know that pH = - log [H+] therefore [H+] = 10-pH

[H+] = 10-2.96

= 1.1 x 10-3 M = 0.0011 M

Consider the equilibrium

CH3COOH ⇄CH3COO- + H+

Initial 0.103 0 0

Change -x +x +x

equlibrium 0.103 -x x x

Ka = x2 / 0.103 - x

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the equilibrium concentration of H+ = x = 0.0011 M

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0.397 mmole of NaOH will convert 0.397 mmole of acetic acid to sodium acetate.

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= 5.1 mmol

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= 0.17 M

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Change -x +x + x

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Initial 0.075 0 0

Change -x +x + x

equilibrium 0.075-x x x

Ka = x2 / 0.075-x = 4.8 x 10-13 [ Ka is given]

neglect x in the denominator as it is very small x2 = 0.075 x 4.8 x 10-13

x =  1.9 x 10-7

Thus the equilirium conce of H+ = 1.9 x 10-7 therefore pH = - log 1.9 x 10-7 = 6.7

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moles of trisodiumphosphate 0.208/ 380 = 0.00055 moles

= 0.55 mmol

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initial 0.055 0 0

Change -x +x +x

equilibrium 0.055-x x x

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