Home Early recorded sounds & wax cylinders Cylinder music shop An Edison commemorative 2nd page Note to early recordings collectors Cylinder of the month Links to related topics What's new Tinfoil resource center Cylinders of the month archive CJ's comics Copyright (C) (P) 1996-2015 Glenn Sage, Portland, Oregon.
1) That looks right. 2) Step 1: Moles=Mass/Mr, so it's 144/72= 2mol. Step 2: Stoichiometry means the ratio of oxygen to pentane is 1:8 so moles of oxygen is moles of pentane times 8. 2*8=16mol of oxygen. Step 3: 16= 9.6*10^24. 3) The ratio of oxygen to carbon in CO2 is 1:2. so it's 192/3 = 64.
Nitrogen monoxide is NO So the molecular weight is 14 (Nitrogen) + 16 (Oxygen) = 30 moles of NO = wt/mw = 22.5 grams / 30 = 0.75 moles We know Avogadro's constant (or Avogadro's number) = 6.02 x 10 ^23 Therefore: number of molecules = Av const x number of moles = 6.02 x 10^23 x 0.75 = 4.515 x 10^23 So the answer is (C).itrogen monoxide is NO So the molecular weight is 14 (Nitrogen) + 16 (Oxygen) = 30 moles of NO = wt/mw = 22.5 grams / 30 = 0.75 moles We know Avogadro's constant (or Avogadro's number) = 6.02 x 10 ^23 Therefore: number of molecules = Av const x number of moles = 6.02 x 10^23 x 0.75 = 4.515 x 10^23 So the answer is (C).