Use the information for the isotopes of element x to calculate the average atomic mass of x, and identify the element. isotope abundance mass (amu) 35x 75.77% 34.969 37x 24.23% 36.965

Answer

36.45 u; X = Cl

Explanation:

The atomic mass of X is the weighted average of the atomic masses of its isotopes.

We multiply the atomic mass of each isotope by a number representing its relative importance (i.e., its percent of the total).

Set up a table for easy calculation .

0.7577  × 34.969 u = 26.496   u

0.2423 × 36.965 u =   8.9566 u

                   TOTAL = 36.45     u

X = Cl

average atomic mass of the element is 35.4536 amu and the element is chlorine.

Explanation:

Mass of isotope 1 = 34.969

% abundance of isotope 1 = 75.77% =

Mass of isotope 2 = 36.965

% abundance of isotope 2 = (24.23)% =

Formula used for average atomic mass of an element :

Therefore, the average atomic mass of the element is 35.4536 amu and the unknown element will be Chlorine.

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.