Construct a numerical problem to illustrate the size of avogadro's number. exchange problems with a classmate and then compare your answers.

In 30 grams of water there are 1.0036*10^24 molecules. Calculate Avogadro's number from these data.

Step-by-step explanation:

The molar mass of water (H2O) is:

2*molar mass of H + molar mass of O

2*1 + 16 = 18 g/mol

This means that 1 mol has a mass of 18 grams. We know that the number of molecules present in 1 mol is the Avogadro's number. From data, we can state the following proportion:

30 g of H2O / 18 g of H2O  = 1*10^24 molecules / x molecules

x = 1.0036*10^24*18/30 ≈ 6.022*10^23 molecules of H2O

This number of molecules corresponds to 1 mol, then it is the Avogadro's number.