Question

Сколько молекул воды содержится в стакане спирта 200мл

Answer 1

1.нужно найти количество вещества в молях 
v=m/Mr=200 гр /Mr(H2O)=200 / 18 = 11,111...моль
2. в 1 моле содержится "число Авогардо" молекул Na = 6,022*10^23
по этому число  молекул в стакане воды 
N=Na*m/Mr= 6,691*10^24 молекул .

Answer 2

Calculating the Number of Water Molecules in 200ml of Alcohol

To calculate the number of water molecules in 200ml of alcohol, we need to consider the molecular formula of alcohol and the density of alcohol.

Molecular Formula of Alcohol: The molecular formula of alcohol is C2H5OH.

Density of Alcohol: The density of alcohol is typically around 0.789 g/ml.

Calculation Steps

1. Calculate the mass of 200ml of alcohol using its density. 2. Convert the mass of alcohol to moles. 3. Use the mole ratio between alcohol and water to find the number of water molecules.

Calculation

1. Calculate the mass of 200ml of alcohol: - Density of alcohol = 0.789 g/ml - Mass = Volume × Density = 200ml × 0.789 g/ml = 157.8g

2. Convert the mass of alcohol to moles: - Molar mass of alcohol (C2H5OH) = 46.07 g/mol - Moles of alcohol = Mass / Molar mass = 157.8g / 46.07 g/mol ≈ 3.43 moles

3. Use the mole ratio between alcohol and water to find the number of water molecules: - The mole ratio between alcohol (C2H5OH) and water (H2O) is 1:1. - Therefore, the number of moles of water = 3.43 moles

Conclusion

In 200ml of alcohol, there are approximately 3.43 moles of water molecules.