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yulyashka [42]
3 years ago
13

If it takes 65.3 min for the concentration of a reactant to drop to 20.0% of its initial value in a first-order reaction, what i

s the rate constant for the reaction in the units min-1?
Chemistry
1 answer:
Anna007 [38]3 years ago
6 0

65.3 \div 20

equals 3.265

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Almost all of the energy that affects the climate on the Earth originates from the Sun.

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Only about 40 per cent of the solar energy intercepted at the top of the atmosphere passes through to the Earth’s surface.

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<u>Answer:</u> The number of molecules of ethinyl estradiol present in one pill are 7.71\times 10^{16}

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Putting values in above equation, we get:

\text{Moles of ethinyl estradiol}=\frac{3.8\times 10^{-5}g}{296g/mol}=1.28\times 10^{-7}mol

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3 years ago
What would you need to do to calculate the molality of 10 g of NaCl in 2 kg of
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Answer:

O B. Convert the 10 g of NaCl to moles of NaCl.

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<h3><em>Please make sure to re-write this on your own so your teacher doesn't think that your cheating!</em></h3>

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