Question

2.38 grams of uranium is heated in a current of air. The resulting oxide

Answer 1

Answer:

$\large \boxed{\text{FALSE}}$

Explanation:

The empirical formula is the simplest whole-number ratio of atoms in a compound.

The ratio of atoms is the same as the ratio of moles.

So, our job is to calculate the molar ratio of U to O.

Data:

     Mass of U = 2.38   g

Mass of UₓOy = 2.806 g

Calculations

1. Calculate the mass of O

Mass of O = 2.806 g - 2.38 g = 0.426 g

2. Calculate the moles of each element

$\text{Moles of U} = \text{2.38 g U} \times \dfrac{\text{1 mol U}}{\text{238.03 g U}} = \text{0.009 999 mol U}\\\\\text{Moles of O} = \text{0.426 g O} \times \dfrac{\text{1 mol O}}{\text{16.00 g O }} = \text{0.026 62 mol O}$

3. Calculate the molar ratio of the elements

Divide each number by the smallest number of moles

U:O = 1:2.663 = 3:7.988 ≈ 3:8

$\text{The simplest molar ratio of U:O is \large \boxed{\mathbf{3:8}} }$