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Lena [83]
2 years ago
9

A certain first-order reaction 45% complete in 65seconds, determine the rate constant and the half life for the process ​

Chemistry
1 answer:
masha68 [24]2 years ago
3 0

The rate constant : k = 9.2 x 10⁻³ s⁻¹

The half life : t1/2 = 75.3 s

<h3>Further explanation</h3>

Given

Reaction 45% complete in 65 s

Required

The rate constant and the half life

Solution

For first order ln[A]=−kt+ln[A]o

45% complete, 55% remains

A = 0.55

Ao = 1

Input the value :

ln A = -kt + ln Ao

ln 0.55 = -k.65 + ln 1

-0.598=-k.65

k = 9.2 x 10⁻³ s⁻¹

The half life :

t1/2 = (ln 2) / k

t1/2 = 0.693 : 9.2 x 10⁻³

t1/2 = 75.3 s

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Calculate the density of an object whose mass is 352 grams and has a volume of 469 mL please show work
mixer [17]

Answer:

<h2>0.75 g/mL</h2>

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We have the final answer as

<h3>0.75 g/mL</h3>

Hope this helps you

4 0
2 years ago
How many molecules of ethanol (c2h5oh) (the alcohol in alcoholic beverages) are present in 140 ml of ethanol? the density of eth
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Then, calculate the number of moles of ethanol by dividing the mass by the molar mass of ethanol equal to 46.07 g/mol.
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Then, multiply the number of moles by the Avogadro's number.
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4 0
3 years ago
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Answer:

A. 1613 °C

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4 0
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When 2.50 g of an unknown weak acid (ha) with a molar mass of 85.0 g/mol is dissolved in 250.0 g of water, the freezing point of
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