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4 years ago

12

The average time it takes for a molecule to diffuse a distance of x cm is given by t=x^2/2D where t is the time in seconds and D

is the diffusion coefficient. Given that the diffusion coefficient of glucose is 5.7 x 10^-7 cm2/s, calculate the time it would take for a glucose molecule to diffuse 10 pm, which is roughly the size of a cell.

1 answer:

evablogger [386]4 years ago

5 0

Answer:

Explanation:

time to diffuse x cm is given by the relation

t = X² /2D

D = 5.7 x 10⁻⁷

t = X² / 2 x 5.7 x 10⁻⁷ = X² x 10⁷ / 11.4 s

X = 10 pm = 10 x 10⁻¹² m = 10 x 10⁻¹⁰ cm = 10⁻⁹ cm

t =( 10 ⁻⁹)² x 10⁷ / 11.4 = 10⁻¹¹ / 11.4 = 8.77 x 10⁻¹³ s

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If 27.3% of a sample of silver-112 decays in 1.52 hours, what is the half-life (in hours to 3 decimal places)?

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<u>Answer:</u> The half life of the sample of silver-112 is 3.303 hours.

<u>Explanation:</u>

All radioactive decay processes undergoes first order reaction.

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where,

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$k=\frac{2.303}{1.52hrs}\log \frac{100}{72.7}\\\\k= 0.2098hr^{-1}$

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Putting values in above equation, we get:

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3 years ago

One sphere has a radions of 181 cm, another has a radius of 5.01 cm. What is the difference in volume (in cubic centimeters) bet

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3 years ago

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<u>Explanation:</u>

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Equilibrium reaction of HA and KA follows the equation:

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Thus, the addition of KA will shift the equilibrium in the left direction.

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