Question

element y reacts with oxygen to form the compound y₂o and has the lowest ionization energy of any period 4 element on the periodic table. identify this element.

Explanation:

Step1: Determine the charge of element Y

In the compound \(Y_2O\), oxygen has a charge of \(- 2\). Let the charge of \(Y\) be \(x\). Using the rule that the sum of charges in a neutral compound is zero: \(2x+(-2) = 0\). Solving for \(x\): \(2x=2\), so \(x = + 1\). Elements with a \(+1\) charge are in Group 1 of the periodic table.

Step2: Identify the Group 1 element in Period 4

The elements in Group 1 are alkali metals. In Period 4 of the periodic table, the Group 1 element is potassium (\(K\)). Also, as we move down a group, ionization energy decreases, and as we move across a period from left to right, ionization energy increases. Since Group 1 elements are on the far left of the periodic table, and within Period 4, potassium (Group 1) has a lower ionization energy compared to other Period 4 elements.

Answer:

Potassium (\(K\))