The isotopes of an element differ in the number or neutrons whereas the number of protons or electrons of a neutral atom stays the same. The molar mass of the element is based on the percent abundances of different isotopes and the individual molar mass of each isotope.
It is a mixture. it can easily be separated.
Answer:
76.1 amu
Explanation:
Let us recall that isomers refer to two different compounds with the same molecular formula but different atom to atom connectivity and different chemical properties. When two compounds are isomers, we can essentially represent them with exactly the same molecular formula.
Now propane-1,2-diol and propane-1,3-diol are both represented by the molecular formula C3H8O2 since they are isomers of each other. When two compounds have the same molecular formula, they must essentially have the same molecular mass. Hence the molecular mass of propane-1,3-diol is also 76.1 amu.
The best answer is the isotope of strontium which is strontium-85. It has a half-life of about 64 days. The metal strontioum has four stable, naturally occurring isotopes which includes 84Sr (0.56%), 86Sr (9.86%), 87Sr (7.0%) and 88Sr (82.58%).