Question

Use your student number to create your values below. Give your answers to the correct number of -ignificant figures. Circle your final answers. The element Mohawkium (Mk) has 3 naturally occurring isotopes: 1. Isotope Atomic Mass Natural Abundance Mk-A 11X. UV amu 1Y. ZU % IS.78 % 7Z. WX % 12.80 am Mk-B 11Y. WX amu Mk-C 11Z. YZ amu Calculate the atomic mass of Mk 2. Calculate the number of moles in Z.YXWg for ferrous oxide. a.5219 How many grams are in X.00 molecules of aluminum sulphate. 2.00 3.

Answer 1

X=2, Y=5, Z=7, U=8, V=0, W=1

atomic masses of three isotopes:

Mk-A: 112.80amu, natural abundance=15.78%

Mk-B: 115.12amu, natural abundance=77.12%

Mk-C: 117.57amu, natural abundance=7.1%

the atomic mass of Mk=$(112.80*15.78+115.12*77.12+117.57*7.1)/(100)$=$114.92$amu

no. of moles in 7.521g of FeO:-

molar mass of FeO=71.84g/mol

71.84g of FeO contains 1 mol FeO

1g of FeO contains 1/71.84 mol FeO

7.521g of FeO contains 7.521/71.84 mol FeO

that is 0.1047moles of FeO

mass of 1 molecule of aluminum sulphate=$342.15*1.66*10^{-24}$

mass of 2.00 molecules of aluminum sulphate=$2.00*342.15*1.66*10^{-24}=1.14*10^{-21}gram$

or

mass of 2.00 molecules of aluminum sulphate=$2.00*342.15=684amu$