Question

question 11
1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s²4d¹⁰5p³6s²
select state
number of electrons= select
element= select

Explanation:

Step1: Calculate number of electrons

The superscripts in the electron - configuration represent the number of electrons in each orbital. Add them up: $2 + 2+6 + 2+6 + 2+10 + 6+2 + 10+3 + 2=55$.

Step2: Identify the element

The atomic number of an element is equal to the number of electrons in a neutral atom. Looking at the periodic table, the element with atomic number 55 is Cesium (Cs).

Step3: Determine the state

Since the electron - configuration is given in the ground - state filling order (lowest energy levels filled first), the state is the ground state.

Answer:

state: Ground state
number of electrons: 55
element: Cesium (Cs)