Question

Determination of Atomic Masses -- Historical

Stanislao Cannizarro (1826-1910) applied Dalton's (1766-1844) Atomic Theory, Avogadro's (1776-1850) Hypothesis, and the experimental methods of Gay-Lussac (1778-1850), to correctly deduce relative atomic masses for various elements.

For example, suppose a nameless element (X) was found to occur in three different substances (A, B and C). The relative molecular masses of A, B, and C were found to be 27.40, 52.90 and 62.60 respectively, compared to an assigned value of exactly 2.00 for H₂. Subsequently, these substances were subjected to elemental analysis and were found to contain 78.1%, 81.1% and 85.6% of X respectively by mass.

What is the (likely) relative atomic mass of X, on this scale?

(Note that this is NOT the same scale as current conventional atomic mass units.)

Work out the mass of X in the each of the molecules A, B, and C from the percentages of X and the molecular masses. Then find the highest common factor (also called the highest common divisor or the greatest common factor).

1pts

Incorrect.

Tries 3/5

Previous Tries

What would be the correct chemical symbol for X?
Note that chemical symbols are case-sensitive.
e.g. Helium is He not he nor HE.

Answer 1