Question

Mr неизвестного вещества равна 28. Образец этого вещества содержит C, n которого =0.30 моль и H, n которого =0.60 моль. Надо установить молекулярную формулу вещества. Ответьте как можно скорей!!!!!!

Answer 1

Соотношение С:Н = 0,3:0,6 = 1:2. Эмипирическая формула будет СН2 и ее молекулярная масса 14. А у нас молекулярная масса 28, т.е. в 2 раза больше, и значит формула будет (СН₂)₂ или просто С₂Н₄ - этилен.

Answer 2

Determining the Molecular Formula of an Unknown Substance

To determine the molecular formula of the unknown substance, we need to analyze the given information about the number of moles of carbon (C) and hydrogen (H) present in the sample.

According to the information provided, the sample contains 0.30 moles of carbon (C) and 0.60 moles of hydrogen (H). The molar ratio between carbon and hydrogen can help us determine the molecular formula of the substance.

To find the simplest whole number ratio between the moles of carbon and hydrogen, we need to divide both values by the smallest number of moles. In this case, the smallest number of moles is 0.30 (the number of moles of carbon).

Dividing 0.30 moles of carbon by 0.30 gives us a ratio of 1. Dividing 0.60 moles of hydrogen by 0.30 gives us a ratio of 2. Therefore, the simplest whole number ratio between carbon and hydrogen is 1:2.

Based on this ratio, we can conclude that the molecular formula of the unknown substance is CH2.