Question

Валентность SeO2Валентность FezO3

Answer 1

Валентность селена 4, а кислорода 2
валентность железа 3, кислород 2

Answer 2

The valency or valence of an element refers to its ability to form chemical bonds with other elements. It indicates the number of electrons an atom can gain, lose, or share when forming chemical compounds.

1. Valency of SeO2 (Selenium dioxide): Selenium (Se) is in Group 16 of the periodic table, also known as Group VIA or Group 6A. Elements in Group 16 typically have a valency of -2 when they form compounds. This means that selenium can gain two electrons to achieve a stable electron configuration like noble gases.

In SeO2, the oxygen (O) atom has a valency of -2, and since there are two oxygen atoms, the overall valency of SeO2 becomes:

Valency of SeO2 = Valency of Se + (Valency of O * Number of O atoms) = +4 + (-2 * 2) = 0

So, the valency of SeO2 is 0.

2. Valency of Fe2O3 (Iron(III) oxide): Iron (Fe) is in Group 8 of the periodic table, also known as Group VIIIB or Group 8B. Iron can exhibit different valencies depending on the compounds it forms. In this case, Fe2O3 is iron(III) oxide, which means the iron (Fe) atoms have a valency of +3.

The oxygen (O) atoms, as mentioned before, have a valency of -2. Since there are three oxygen atoms in Fe2O3, the overall valency becomes:

Valency of Fe2O3 = (Valency of Fe * Number of Fe atoms) + (Valency of O * Number of O atoms) = (+3 * 2) + (-2 * 3) = +6 - 6 = 0

So, the valency of Fe2O3 is 0.

To summarize:

• The valency of SeO2 is 0.
• The valency of Fe2O3 is 0.