3. a.) The initial reaction when an automobile airbag deploys is: 2NaN3(s) → 2Na(s) + 3N2(g). If 125.0g of NaN3 reacts, how many liters of N2 gas result at 25.0oC and a pressure of 1.00 atmosphere?

3. b.) The recent death of a former soviet spy is attributed to the effects of an isotope of Polonium with an atomic number of 84 and a mass number of 210. This isotope is an alpha emitter. What are the atomic number, mass number and name of the element produced when one of the polonium atoms emits an alpha particle?

3. c.) Polonium 210 has a half life of 138 days. If an initial sample of it has a mass of 1.50 grams, how many grams of it remain after:
A. 138 days ? B. 2(138) = 376 days ? C. 3(138) = 414 days ?

Solution Preview

The initial reaction when an automobile airbag deploys is:

2 NaN3(s) → 2 Na(s) + 3 N2(g).

If 125.0 g of NaN3 reacts, how many liters of N2 gas result at 25.0 degrees C and a pressure of 1.00 atmosphere?

Response:

Let us first convert 125.0 g of NaN3 into moles of NaN3. We do this by first working out the molar mass of NaN3. It is 65.01 g/mol.

(1 mol/65.01 g)(125.0 g) = 1.923 mol

Therefore, we react 1.923 mol of NaN3. Now, we set up a little ratio to figure out moles of N2 produced. From the stoichiometry of the balanced chemical equation, we know that 2 moles of NaN3 react to produce 3 moles of N2.

Therefore, 2 is to 3 as 1.923 is to x.

2/3 = 1.923/x

x = 2.88

Therefore, ...

Solution Summary

This solution provides detailed answers to three questions regarding atmosphere, atomic weight, and mass.

... 1) Atomic mass is expressed in atm. (a) Correct (b) Incorrect. ... (a) True (b) False. 6) Formula weight is the sum of atomic weights in a chemical formula. ...

... the number of moles of C8H18, molecular weight=114.2g ... What are the atomic and mass numbers of the resultant ... 5. What is the pressure in atmospheres of 125 grams ...

... gives X = 35.3 which is the Atomic weight of Chlorine. ... 1271 mg = 355.88mg Molecular weight of FeCl 3 ... R * Kelvin Temperature = 2.69 * 0.0821 * 298 = 65.813 atm. ...

... the following for this second reaction: a. Mass of zinc ... For example, at one atmosphere, the molar volume of any ... the grams of zinc by the atomic weight of zinc. ...

... gas law, we have: ρRT P= MW mL ⋅ atm ρ 821 ... of mass that is used to express an atomic mass and ... an error in the measurement in the weight of the ...

... time of Cl-36 in the atmosphere is about 1 ... products of extinct radionuclides with a mass spectrometer and ... in their nuclei but different atomic weights owing to ...

... a. Weight b. Volume c. Density d. Buoyancy. ... 49. In which layer of the atmosphere does weather occur? ... Which process was used in the Atomic Bomb? ...

... A. Weighing by Difference and the Mole Concept Results 15.60 g ... the ratio to match the ratio of atomic masses 118.71 _ g _ ... _ mol × 0.08206 _ L _ atm / K / mol ...

... which is undergoing rapid inert atmosphere, are concentration ... data (solid line) (in k1-weighting) and calculated ... acetylene binds to metallacy- atomic ion and ...

... is the temperature (in kelvins) of the atmosphere at that ... is 295 K. An argon atom (atomic mass = 39.948 u ... the number of moles x the molecular weight divided by ...