A compound contains 54.52% carbon, 9.17% hydrogen, and 36.31% oxygen by mass. A sample weighing 3.023 grams has a volume of 2.00L at 25.0oC and 0.420 atm. a. Calculate the empirical formula of the compound.

Empirical formula is C₂H₄O

Explanation:

We assume, the compound is an ideal gas, so we apply the Ideal Gases law, to determine the moles:

P . V = n . R . T

We convert T° → 25°C + 273 = 298K

0.420 atm . 2L = n . 0.082 . 298K

n = (0.420 atm . 2L) / (0.082 . 298K) → 0.0343 moles

This moles are 3.023 g, so now, we can confirm the molar mass:

3.023 g / 0.0343 mol = 87.9 g/mol ≅ 88 g/m

Centesimal composition is: 54.52 % of C, 9.17 % of H, 36.31% of O.

100 g of compund are contained in: 100 g . 1mol / 87.9g = 1.14 moles

We state the moles of each element:

54.52 g / 12g/mol = 4.5 mol of C

9.17 g / 1g/mol = 9.17 mol of H

36.31 g / 16 g/mol = 2.3 moles of O

Then, we state:

In 1.14 moles of compound we have 4.5 moles of C

In 1 mol we may have (4.5 / 1.14) = 3.94 moles of C → 4C

In 1.14 moles of compound we have 9.17 moles of H

In 1 mol, we may have (9.17 / 1.14) = 8.04 moles of H → 8H

In 1.14 moles of compound we have 2.3 moles of O

In 1 mol we may have, (2.3 / 1.14) = 2 moles of O

Molecular formula is C₄H₈O₂

We confirm it by the molar mass: 12 g/m . 4 + 1g/m . 8 + 16g/m . 2 = 88g/m

Empirical formula will be (with the lowest subscripts) → C₂H₄O

hurricanes form when warm, moist air from the ocean surface quickly rises into the atmosphere and forms storm clouds and rain. when the clouds are formed, heat is released which warms the cool air in the upper regions of the atmosphere so that the cycle can continue. which two phases of the water cycle are repeated in this process?