Question
On what does the work function of a metal depend?

Answer

The value of work function depends on temperature. But since this dependence is negligible, it can be considered fixed for the substance. The work function is expressed as $W _0$ or $\phi_0$. Its value is different for different substances. For tungsten its value is around 4.5 eV . Its value is very small for alkali metals. For sodium its value is 1.5 eV .

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