Question

1. Which element has the electron configuration:

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d⁵ ?

a. Br

b. Mn

c. Nb

d. Tc

2. What is the value of 27^oC on the Fahrenheit scale?

Group of answer choices

a. -6.8

b. 106

c. 300

d. 81

e. none of these

3.

Which of the following atoms has the largest radius?

Group of answer choices

a. S

b. Se

c. Br

d. O

Answer 1

Qn1.

According to the electron configuration the element has 43 electrons. So the atomic number of the element is also 43. This is the atomic number of Technetium.

Technetium of Tc has this electron configuration.

Qn2.

We know, C /5=( F -32)/9

where, C = Temperature in celcius

F= Temperature in Fahrenheit

So, F -32 = (27/5)×9

F = 80.6 or ~81

So the answer is 81 .

Qn3.

Se atom has the largest radius.

Selenium has the largest atomic radius.