calculate the number of malecules in a drop of water weighting 0.09 g
.09g * 1mole/18g * 6.02*10^23mol/mole = 3.01*10^21 molecules
To calculate the number of molecules in a drop of water, we need to know the molecular weight and the number of moles in the given mass.
1. Determine the molecular weight of water:
The molecular formula for water is H2O, with an atomic weight of hydrogen (H) as 1 and the atomic weight of oxygen (O) as 16.
So, the molecular weight of water (H2O) is:
2(1 H) + 1(16 O) = 2 + 16 = 18 g/mol.
2. Calculate the number of moles:
Given the mass of water as 0.09 grams, we can calculate the number of moles using the formula:
moles = mass / molecular weight.
moles = 0.09 g / 18 g/mol = 0.005 moles.
3. Calculate the number of molecules:
The number of molecules is given by Avogadro's number, which is 6.022 × 10^23 molecules per mole.
Number of molecules = moles × Avogadro's number
Number of molecules = 0.005 moles × 6.022 × 10^23 molecules/mole = 3.011 × 10^21 molecules.
Therefore, there are approximately 3.011 × 10^21 molecules in a drop of water weighing 0.09 grams.