The work function of sodium is 2.28 V.
(i) What is the minimum energy for a quantum of radiation to cause photoelectric emission from a sodium surface?
(ii) Calculate the wavelength of this radiation.

Explanation

To solve the problem step by step, let's break it down into two parts as per the question.

### Part (i): Minimum Energy for Photoelectric Emission

1. **Understanding Work Function**: The work function (φ) is defined as the minimum energy required to remove an electron from the surface of a material. For sodium, the work function is given as 2.28 eV.

2. **Minimum Energy Calculation**: Since the work function is already given in electron volts (eV), the minimum energy (E) required for a quantum of radiation to cause photoelectric emission from sodium is equal to the work function:
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