Consider the following chemical equation. how many moles of seоg can be produced from 35
g of oxygen and excess selenium?
2se +302 - 2so3

0.73 mole

Explanation:

Data Given

mass of O₂= 35 g

moles of SeО₃ = ?

Reaction Given:

                    2Se + 3O₂ > 2SeO₃

Solution:

First find the mass of SeO₃ from the reaction that it produced from how much mass of oxygen (O₂).

Look at the balanced reaction

                     2Se  +    3O₂   >  2SeO₃

                                  3 mol               2 mol

So 3 mole of O₂ Produce 2 moles of SeO₃

Now

convert the moles into mass for which we have to know molar mass of SeO₃ and O₂

Molar mass of SeO₃

Molar mass of SeO₃ = 79 + 3(16) = 79 + 48

Molar mass of SeO₃ = 127 g/mol

mass of SeO₃

                    mass in grams = no. of moles x molar mass

                    mass of SeO₃ = 2 mol x 127 g/mol

                    mass of SeO₃ = 254 g

Molar mass of O₂ = 2(16)

Molar mass of O₂= 32 g/mol

mass of O₂

                  mass in grams = no. of moles x molar mass

                   mass of O₂ = 3 mol x 32 g/mol

                    mass of O₂ = 96 g

So,

96 g of O₂ Produce 254 g of SeO₃, then how many grams of SeO₃ will produced from 35.0 grams of O2

Apply unity Formula

                     96 g of O₂ ≅ 254 g of SeO₃

                     35 g of O₂ ≅ X g of SeO₃

By cross multiplication

                     X g of SeO₃ = 254 g x 35 g / 96 g

                     X g of SeO₃ = 92.6 g

92.6 g of SeO₃ will produce from 35 g of O₂

Now,

we will convert mass into moles

Formula used

                  no. of mole = mass in g / molar mass              

Put values in above equation

                  no. of mole = 92.6 / 127 g/mol

                  no. of mole SeO₃ = 0.73 mol

SeO₃ = 0.73 mole

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

explanation: