what is the molecular formula of oxide of arsenic in its gaseous state (also I need to explain how this formula came about )??

There are two arsenic oxides. One is As2O3 and the other is As2O5. How did that come about? Please clarify. I assume you have some data; previous posters have had percent composition or grams to work with and the correct formula was determined from that. If that is the case with you please post all of your question. We can answer questions better if we know specificis and not generalities.

To determine the molecular formula of the oxide of arsenic in its gaseous state, we need additional information like the percent composition or grams of the elements involved. Without specific data, we cannot accurately determine the molecular formula.

However, I can provide information on how the molecular formulas As2O3 and As2O5 came about for the two arsenic oxides.

Arsenic forms two main oxides: arsenic(III) oxide (As2O3) and arsenic(V) oxide (As2O5). The Roman numerals in parentheses represent the oxidation states of arsenic.

1. Arsenic(III) oxide (As2O3):
Arsenic(III) oxide is formed when arsenic reacts with oxygen in a 2:3 ratio. The balanced equation for the reaction is:
4 As + 3 O2 -> 2 As2O3

2. Arsenic(V) oxide (As2O5):
Arsenic(V) oxide is formed when arsenic reacts with oxygen in a 2:5 ratio. The balanced equation for the reaction is:
2 As + 5 O2 -> As2O5

The molecular formulas for these oxides were determined by analyzing the stoichiometry of the reactions, which means looking at the ratios of the elements involved in the chemical reaction. By balancing the equation, we determine the ratio of the elements in the resulting compound.

However, it is important to note that these molecular formulas were derived based on stoichiometry and may not accurately reflect the actual molecular structure of the oxides in their gaseous states. For a more precise understanding of the molecular structure, additional experimental techniques like spectroscopy or crystallography would be required.