Question

C=40%H=2,7%O=53,3%Mr=30CxHyOz-?​

Answer 1

Ответ:

40/12 = 3.33/2.7 = 1.23 × 4 = 5

2.7/1 = 2.7/2.7 = 1 × 4 = 5

53.3/16 = 3.33/2.7 = 1.23 × 4 = 5

Answer 2

To find the molecular formula for a compound given the percentages of its constituent elements, you can follow these steps:

1. Convert the percentages to grams.
2. Calculate the moles of each element.
3. Determine the simplest whole number ratio of the moles.
4. Write the molecular formula.

Given the percentages:

• Carbon (C) = 40%
• Hydrogen (H) = 2.7%
• Oxygen (O) = 53.3%

Let's assume we have 100 grams of the compound. Then:

1. Convert the percentages to grams:

   • Carbon (C) = 40% of 100g = 40g
   • Hydrogen (H) = 2.7% of 100g = 2.7g
   • Oxygen (O) = 53.3% of 100g = 53.3g

2. Calculate the moles of each element:

   • Moles of C = 40g / atomic mass of C = 40g / 12.01 g/mol ≈ 3.33 moles
   • Moles of H = 2.7g / atomic mass of H = 2.7g / 1.01 g/mol ≈ 2.67 moles
   • Moles of O = 53.3g / atomic mass of O = 53.3g / 16.00 g/mol ≈ 3.33 moles

3. Determine the simplest whole number ratio of the moles. In this case, it appears that the ratio of moles is approximately 1:1:1 for C:H:O.

4. Write the molecular formula based on the whole number ratio:

   • C1H1O1
   • Since subscripts of 1 are typically not written in molecular formulas, the molecular formula simplifies to just "CHO."

So, the molecular formula for the compound is "CHO." However, it's essential to note that this simplified formula may not provide the actual structural information of the compound, as there could be multiple compounds with the same elemental composition but different structures.