6. Determine the molar mass of an unknown gas that has a volume of 72.5 mL at a temperature of 68.0°C, and a pressure of 0.980 atm, and a mass of 0.207 g.
(hint: find moles first and remember that molar mass is the mass per mole”)

Radon-222 or rn-222 has a half-life of 3.82 days. to determine the fraction of an original sample of rn-222 that remains unchanged after 7.646 days, we calculate the amount of rn-222 remaining after 7.646 days and divide it with the original amount. using 1 gram as a basis and using half-life calculation methods, we can determine that  0.249 or 0.25  grams of rn-222 will remain, and thus the fraction remaining is 0.25 or 1/4.

Ithink the correct answer is 3

#2- the hno3 has a h+ ion and the naoh has an oh- ion

The answer to this qustion is c