Question

Сколько молекул содержится в 100 г. воды при 20 С

Answer 1

Дано:

m (H2O) = 100мг = 0,1 г

Найти: N(H2O)

n(H20) = m/M = 0,1/18 = 0,0056 моль

N(H2O) = n*Na = 0,0056*6*20(в 23-й степени) = 0,03*20 (в 23-й степени)

Answer 2

Calculation of the Number of Molecules in 100g of Water at 20°C

To calculate the number of molecules in 100g of water at 20°C, we need to use the concept of molar mass and Avogadro's number.

The molar mass of water (H2O) is approximately 18.01528 grams per mole Avogadro's number is approximately 6.022 x 10^23 molecules per mole.

To find the number of moles in 100g of water, we divide the mass by the molar mass:

Number of moles of water = mass of water / molar mass of water

Number of moles of water = 100g / 18.01528 g/mol

Now, we can calculate the number of molecules using Avogadro's number:

Number of molecules = number of moles of water x Avogadro's number

Number of molecules = (100g / 18.01528 g/mol) x (6.022 x 10^23 molecules/mol)

Please note that the molar mass of water and Avogadro's number are approximate values, and the actual values may vary slightly.

Let's calculate the number of molecules in 100g of water at 20°C:

Number of molecules = (100g / 18.01528 g/mol) x (6.022 x 10^23 molecules/mol)

Number of molecules = 5.548 x 10^24 molecules

Therefore, there are approximately 5.548 x 10^24 molecules in 100g of water at 20°C.

Please let me know if there's anything else I can help you with!