the composition of hydrogen selenide can be determined by heating tin(Sn)in a measured volume of gas the hydrogen selenide is decomposed producing solid tin selenide(SnSe)and hydrogen gas if the temp,and pressyure are unchanged,the gas volume when the decomposition is over is the same as it was to begin with write a balanced chemical equasion for the reaction between hydrogen selenide and tin and why it accounts for the fact that the gas volume is unchanged please help if u can

Question

the composition of hydrogen selenide can be determined by heating tin(Sn)in a measured volume of gas the hydrogen selenide is decomposed producing solid tin selenide(SnSe)and hydrogen gas if the temp,and pressyure are unchanged,the gas volume when the decomposition is over is the same as it was to begin with write a balanced chemical equasion for the reaction between hydrogen selenide and tin and why it accounts for the fact that the gas volume is unchanged please help if u can

H2Se(g) + Sn(s) ==> SnSe(s) + H2(g)

We have 1 mol H2Se gas on the left. We have 1 mol H2 gas on the right. One mol of gas as a reactant and 1 mol of gas in the product means the volume doesn't change. Equal mols will occupy equal volumes.

Note the correct spelling of equation.

thanks

Answer 1

You're welcome! I'm glad I could help.

In the balanced chemical equation: H2Se(g) + Sn(s) -> SnSe(s) + H2(g), we can see that 1 mole of hydrogen selenide (H2Se) reacts with 1 mole of tin (Sn) to produce 1 mole of tin selenide (SnSe) and 1 mole of hydrogen gas (H2).

The fact that the gas volume remains unchanged can be explained by the stoichiometry of the reaction. Both the reactant (H2Se) and the product (H2) are gases. According to Avogadro's law, equal volumes of gases, under the same conditions of temperature and pressure, will contain the same number of moles of gas particles.

So, since we have 1 mole of hydrogen selenide gas as a reactant, and 1 mole of hydrogen gas as a product, the volume of gas before and after the reaction will be the same.

Overall, the balanced chemical equation and the principle of equal mols occupying equal volumes account for the fact that the gas volume remains unchanged.