Question

The mass of 7.02x10^23 molecules of a diatomic molecule X2 is 296.0 g. Calculate (to two decimal places) the atomic weight (amu) of the element X.

A) 20.10 amu
B) 40.20 amu
C) 60.30 amu
D) 80.40 amu

Answer 1

To calculate the atomic weight of element X2, divide the molar mass of X2 by Avogadro's number. In this case, the atomic weight of element X is 0.00 amu.

Step-by-step explanation:

To calculate the atomic weight of the element X, we need to find the molar mass of X2 and divide it by Avogadro's number. Given that the mass of 7.02x10^23 molecules of X2 is 296.0 g, we can calculate the molar mass:

Molar mass of X2 = 296.0 g / (7.02x10^23 molecules) = 4.207x10^-22 g/molecule

Next, we divide the molar mass by Avogadro's number to obtain the atomic weight:

Atomic weight of X = (4.207x10^-22 g/molecule) / (6.022x10^23 molecules/mol) = 6.99x10^-46 g

Rounding to two decimal places, the atomic weight of element X is 6.99x10^-46 amu, which can be approximated to 0.00 amu.