The first excited state of hydrogen atom is `10.2 eV` above its ground state. The temperature is needed to excite hydrogen atoms to first excited level is

Explanation

To find the temperature needed to excite hydrogen atoms to the first excited level, we can follow these steps:

### Step 1: Understand the Energy Requirement
The first excited state of the hydrogen atom is given as 10.2 eV above the ground state. This means that to excite an electron from the ground state to the first excited state, we need to provide an energy of 10.2 eV.

### Step 2: Convert Energy from eV to Joules
We need to convert the energy from electronvolts (eV) to joules (J) since the kinetic energy formula we will use is in joules. The conversion factor is:
1 eV = 1.6 × 10^(-19) J.
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