Ideal gas law PV = nRT or PM = dRt ( M is molecular mass of gas ) and d is gas density
where m/ M ( m is mass of gas sample )
m = dRT / P ( 2.78 g/L ) ( 0.082 L atm/ K mole )( 310K ) / 1.2 atm =
58.9 g/mol
gas must be butane ( C4H10) has molecular mass = 58.9 g/mol
Answer:
24.32 amu
Explanation:
From the question given above, the following data were obtained:
Isotope A (Mg–24):
Mass of A = 24 amu
Abundance (A%) = 79%
Isotope B (Mg–25):
Mass of B = 25 amu
Abundance (B%) = 10%
Isotope C (Mg–26):
Mass of C = 26 amu
Abundance (C%) = 11%
Average atomic mass of Mg =?
Average atomic mass = [(Mass of A × A%)/100] + [(Mass of B × B%)/100] + [(Mass of C × C%)/100]
= [(24 × 79)/100] + [(25 × 10)/100] + [(26 × 11)/100]
= 18.96 + 2.5 + 2.86
= 24.32 amu
Thus, the average atomic mass of Mg is 24.32 amu
Mg: [Ne] 3s2. The second ionization energy of Mg is larger than the first because it always takes more energy to remove an electron from a positively charged ion than from a neutral atom. The third ionization energy of magnesium is enormous, however, because the Mg2+ ion has a filled-shell electron configuration.
