The naturally occurring isotopes of magnesium are magnesium-24. magnesium-25, and magnesium-26. magnesium-24 has an abundance of 78.994% and a mass of 23.985 amu. magnesium-25 has an abundance of 10.001% and a mass of 24.986 amu. magnesium-26 has an abundance of 11.013% and a mass of 25.983 amu. calculate the average atomic mass of magnesium.

The average atomic mass of magnesium is 24.307 amu.  

Explanation:

Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.  

Formula used to calculate average atomic mass follows:

  .....(1)

Mass of isotope = 23.985 amu

Percentage abundance of isotope = 78.994 %

Fractional abundance of isotope = 0.78994

Mass of isotope = 24.986 amu

Percentage abundance of isotope = 10.001 %

Fractional abundance of isotope = 0.10001

Mass of isotope = 25.983 amu

Percentage abundance of isotope = 11.013 %

Fractional abundance of isotope = 0.11013

Putting values in equation 1, we get:  

Hence, the average atomic mass of magnesium is 24.307 amu.

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

explanation:

they it depends on if one believes about radioactivity, they make a geiger counter beep but maybe it was going to beep anyway electronics do wierd things all the time or it was programmed to beep near certain metals.