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Answer:
Empirical formula is PNCl₂
Explanation:
Percent composition means that 100 g of compound has x g of each element.
In 100 g of compound x, we have 26.73 g of P, 12.09 g of N, 61.18 g of Cl.
So, let's make some rules of three:
In 100 g of compound we have 26.73 g of P, 12.09 g of N, 61.18 g of Cl
In 579.43 g of compound we have:
(579.43 . 26.73) / 100 = 155 g of P
(579.43 . 12.09) / 100 = 70 g of N
(579.43 . 61.18) / 100 = 354 g of Cl
Let's convert the mass of the elements in moles.
155 g of P / 30.97 g/mol = 5 P
70 g / 14 g/mol = 5 N
354 g / 35.45 g/mol = 10 Cl
Answer:- 9.98 grams.
Solution:- The given balanced equation is:

From this equation, there is 1:1 mol ratio between methanol and formic acid. We start with given grams of methanol and convert them to moles. Then using mol ratio the moles of foramic acid are calculated and finally converted to grams on multiplying by it's molar mass.
The calculations could easily be done using dimensional analysis as:

= 
Hence, 9.98 grams of formic acid can be formed from 6.95 grams of methanol.