Answer:
Two conversion factors:

Explanation:
You can create two possible <em>conversion factors</em>, one to convert from mL to L, and one to convert from L to mL
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<u>a) From mL to L</u>
To convert mL to L you need to multiply by a conversion factor that has mL on the denominator and L in the numerator.
Your starting point is: 
Then, divide both sides by 1,000mL (this will be on the denominator of the fraction);

<u>b) From L to mL</u>
Divide both sides by 1 L:

Answer:
6.50 g of Hydrogen
Explanation:
We know that in every 20.0g of sucrose, there are 1.30g of hydrogen.
We now have 100.0g of sucrose. 100.0g is 5x larger than the 20.0g sample, which is a 5 : 1 ratio. Applying this ratio to the amount of hydrogen, we would have 5*1.3g of hydrogen in the 100.0g of sucrose.
5*1.3 = 6.5, so our answer is that there are 6.50g of hydrogen in 100.0g of sucrose.
Hope this helps!
Answer:51.1%
Explanation:
Mass percent : It is defined as the mass of the given component present in the total mass of the compound. Formula used : First we have to calculate the mass of and . Mass of = 18 g/mole Mass of = 7 × 18 g/mole = 126 g/mole Mass of = 246.47 g/mole Now put all the given values in the above formula, we get the mass percent of in . Therefore, the mass percent of in is, 51.1%