Question

an element has a lower electronegativity than boron and 1 valence electron. where is the element located on the p.t.?
group 17, period 3
group 1, period 2
group 7, period 4

Explanation:

Step1: Recall electronegativity trend

Electronegativity increases across a period and decreases down a group in the periodic table. Boron (B) is in Group 13, period 2. Elements with lower electronegativity than boron are likely to be below and to the left of boron.

Step2: Consider valence - electron condition

Elements in Group 1 have 1 valence electron.

Step3: Determine the position

The element with 1 valence electron (Group 1) and lower electronegativity than boron (so likely in a lower - numbered period or same period but to the left) is in Group 1, period 2.

Answer:

Group 1, period 2