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3 years ago

A sample of sugar (C12H22O11) contains 1.505 × 1023 molecules of sugar. How many moles of sugar are present in the sample?

2 answers:

7 0

1 mole ------------ 6.02x10²³ molecules
? moles ----------- 1.505x10²³ molecules

(1.505x10²³) x 1 / ( 6.02 x10²³ ) =

(1.505x10²³) / ( 6.02x10²³ ) =

= 0.25 mol

Answer A

hope this helps!

saveliy_v [14]3 years ago

6 0

Answer: Option (a) is correct.

Explanation:

Molecules of sugar given = $1.505 \times 10^{23}$

According to Avogadro's number it is known that 1 mole contains $6.023 \times 10^{23}$ .

Therefore, calculate the moles of sugar present in the sample as follows.

Number of moles = $\frac {1.505 \times 10^{23}}{6.023 \times 10^{23}}$

= 0.25 mol

Thus, the moles of sugar present in the sample is 0.25 mol.

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4 years ago

Calculate the volume of chlorine at stp that would be required to act completely with 3.70g of dry slaked line

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The slaked lime Ca(OH)2, reacts with chlorine, Cl2, as follows:

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To solve this question we must find the moles of slaked lime added. With these moles we can find the moles of chlorine required and its volume at STP as follows:

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And V is volume, our incognite:

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<h3>The volume required is 2.24L</h3>

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3 years ago

Perform the following for Part C of this lab:

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There is some info missing. I will use some values to show you the procedure and then you can replace them with your values.

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