Question

In: Chemistry

1. Calculate the molecular mass (in g/mole) for heavy water, D2O, where D is 2H. 2....

1. Calculate the molecular mass (in g/mole) for heavy water, D2O, where D is 2H.

2. Calculate based on the relative abundance of the three main isotopes of silicon the average atomic mass of Si and compare your results with the value in your Table of Elements (28Si(92.2%), 29Si(4.7%), (30Si(3.1%))

3. Calculate the molar mass of H2SO4 , KClO4, and H3PO4.

4. How many grams of deuterium (D is 2H) are in 50 grams of Heavy water (D2O)?

5. A helium balloon is launched into the atmosphere. If balloon's volume is 4.19x103 liters at 22.5 C and the atmospheric pressure is 754 mm Hg, what will be the balloon's volume at a height of 20 miles where the pressure is 76 mm Hg and the temperature is -33 C.

No helium is escaped from the balloon. Hint: use the ideal gas law at constant umber of moles (n). Temperature should be expressed in K.

Expert Solution

1. MOLECULAR MASS OF D2O = 2*2 + 16 = 20g/mole

2.

average atomic mass =1st isotope abundance * atomic mass + 2nd isotope abundance + atomic mass +3rd isotope abundance + atomic mass

= 0.922*28+0.04*29+0.03*30 = 27.876g

3.

molar mass of H2SO4 = 1*2 + 32*1 + 16*4 = 98g/mole

molar mass of KClO4 = 39+35.5 + 16*4 = 138.5g/mole

molar mass of H3PO4 = 1*3 + 31*1 + 16*4 = 98g/mole

4.

1 mole of D2O contains 2 mole of D

20g of D2O contains 4g of D

50g of D2O contains = 4*50/20 =10g of D

queen_honey_blossom answered 2 years ago

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