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3 years ago

Heelppppppppppjgjghjhjhj

Chemistry

1 answer:

Grace [21]3 years ago

7 0

4. (1)/[1(12)+4(1)] = 25%

I'm pretty sure this is your answer.

<h3>If you need to see this solved easier, no worries! =</h3>

4. 4 / 16 = 25%

I hope this helped! Good luck.

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4 years ago

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A particular oral contraceptive contains 0.038 mg of ethinyl estradiol in each pill. The formula of this compound is C20H24O2. H

Ray Of Light [21]

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

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Given mass of ethinyl estradiol = 0.038 mg = $3.8\times 10^-5}g$ (Conversion factor: 1 g = 1000 mg)

Molar mass of ethinyl estradiol $(C_{20}H_{24}O_2)=[(20\times 12)+(24\times 1)+(2\times 16)]=296g/mol$

Putting values in above equation, we get:

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

According to mole concept:

1 mole of a compound contains $6.022\times 10^{23}$ number of molecules

So, $1.28\times 10^{-7}mol$ of ethinyl estradiol will contain = $(1.28\times 10^{-7}\times 6.022\times 10^{23})=7.71\times 10^{16}$ number of molecules

Hence, the number of molecules of ethinyl estradiol present in one pill are $7.71\times 10^{16}$

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3 years ago

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The oxygen has more electrons, AND 2 lone pairs - the Hydrogens will be partially positive, and so such a way shows the polarity; am arrow with +-> on the Hydrogen area. The “point” will have a negative sign; usually these are drawn as “partially positive” & “partially negative”, but I can’t draw that. Sorry.

Explanation:

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