Which of the following contains the smallest number of molecules. 1g H2O 1g NH3
ID: 919166 • Letter: W
Question
Which of the following contains the smallest number of molecules.1g H2O 1g NH3 1g H2 1gO2 All are the same Chapter 5 Exercises (You may use a periodic table as needed.) I. If a single a single molecule of a substance weighs 7.64 x 1023 g, what is its molar mass I wile 2. W hich of the following contains the smallest number of molecules? A. 1.0 g H2O B. 1.0 g NH, C. 1.0 g H2 D. 1.0 g O2 E. all of the above are the same 3. Ethanol (C,H,OH) has a density of 0.789 g/ml. How many ethanol molec are in a teaspoon (5 mL) of ethanol? 4. 1023 atoms of zinc weigh nearly the same
Explanation / Answer
The one containging smallest no of molecules will have the smallest no of moles.
moles of H2O in 1g of H2O =
moles of H2O in 1g of H2O = 0.055
moles of NH3 in 1g of NH3 = 0.059
moles of H2 in 1g of H2 =0.5
moles of O2 in 1g of O2 = 0.031
As the no of molecules present in the above can be given by multiplying moles with Avogadro no,
O2 will have smallest no of molecules.