Question

Сколько молекул воды находиться в стакане обемом 250 см^3 если он полностью заполнен водой?

Answer 1

$N= \frac{m}{M} *Na= \frac{0,25}{0,018} *6*10^{23}=8,3*10^{24}$

Answer 2

Calculating the Number of Water Molecules in a 250 cm^3 Glass

To calculate the number of water molecules in a 250 cm^3 glass, we can use the concept of molar volume and Avogadro's number.

Molar Volume: The molar volume of any gas at standard temperature and pressure (STP) is 22.4 liters or 22,400 cm^3 per mole. This means that one mole of any gas occupies 22.4 liters or 22,400 cm^3 at STP.

Avogadro's Number: Avogadro's number is 6.022 x 10^23, which represents the number of atoms, ions, or molecules in one mole of a substance.

Calculation

To find the number of water molecules in a 250 cm^3 glass, we can follow these steps:

1. Convert Volume to Liters: - 250 cm^3 is equal to 0.25 liters.

2. Determine the Number of Moles of Water: - Using the molar volume, we can calculate the number of moles of water in the given volume. - Number of moles = Volume (in liters) / Molar volume - Number of moles = 0.25 liters / 22.4 liters/mole

3. Calculate the Number of Water Molecules: - Once we have the number of moles, we can use Avogadro's number to find the number of water molecules. - Number of molecules = Number of moles * Avogadro's number

Let's calculate the number of water molecules in a 250 cm^3 glass using the above steps.

Result

The number of water molecules in a 250 cm^3 glass, when it is completely filled with water, is approximately 1.06 x 10^23 molecules.

This calculation is based on the molar volume of gases and Avogadro's number, which are fundamental concepts in chemistry