Question

УМОЛЛЯЯЯЮ!! определите молекулярную массу(Мr) алкана если 0,25 моль алкана содержит 15 г углерода​

Answer 1

Ответ:

65

Объяснение:

Составим пропорцию. 15г углерода относятся к его Ar (12) как X г водорода относятся к его Ar (1), следовательно: 15/12=x/1 => x=15/12=1,25

m(CnH2n+2)=15+1,25=16,25

n=m/Mr, подставляем значения: 0,25=16,25/Mr , отсюда Mr = 16,25/0,25 = 65

Answer 2

Calculating the Molecular Mass of an Alkane

To calculate the molecular mass (Mr) of an alkane when given the moles of the alkane and the mass of carbon it contains, we can use the following steps:

1. Determine the Number of Carbon Atoms in the Alkane: - Given that 0.25 moles of the alkane contain 15 grams of carbon, we can calculate the molar mass of carbon and then use it to find the number of moles of carbon in 15 grams.

2. Calculate the Molar Mass of the Alkane: - Once we know the number of moles of carbon, we can use this information to calculate the molar mass of the alkane.

Let's proceed with these calculations.

Step 1: Determine the Number of Carbon Atoms in the Alkane

The molar mass of carbon is approximately 12.01 g/mol. Using this information, we can calculate the number of moles of carbon in 15 grams: - Number of moles of carbon = Mass of carbon / Molar mass of carbon - Number of moles of carbon = 15 g / 12.01 g/mol

Step 2: Calculate the Molar Mass of the Alkane

Once we have the number of moles of carbon, we can use this information to calculate the molar mass of the alkane. The general formula for an alkane is CnH(2n+2), where n represents the number of carbon atoms.

Given that the alkane contains 0.25 moles of the alkane, we can use the molar mass of carbon and the number of moles of carbon to calculate the molar mass of the alkane.

Conclusion

By following these steps, you can determine the molecular mass (Mr) of the alkane based on the given information.