aswer: protactinium-234 is more dang erous than uranium
The volume of the gas that occupy at STP is 165. 28 cm^3
calculation
by use of combined gas law that is P1V1/T1=P2V2/T2, where
P1=84.6 kpa
T1=23.5 +273=296.5 K
V1=215 cm^3
At STP T= 273 K and P= 101.325 Kpa
therefore p2 = 101.325 Kpa and T2 = 272 K V2=?
by making V2 the subject of the formula V2 =T2P1V1/P2T1
V2 = 273 K x 84.6 Kpa x 215 cm^3/ 101,.325 Kpa x296.5 K =165.28 cm^3
The answer to letter b is
☀️
Molar mass of 
<u>As we know</u>–
1 mol =
formula units
1 mol = 143.092 g = formula units
Henceforth –
formula units –
Answer:
D number of protons or atomic mass
