The work function of indium is 6.56 x 10^-19 j. what is the minimum frequency of a photon that will eject an electron from the indium metal surface?
1. 9.90 x 10^14 hz
2. 2.97 x 10^23 hz
3. 3.42 x 10^14 hz
4. 4.57 x 10^26 hz
5. 2.19 x 10^-27 hz

1. 9.90 x 10^14 Hz

Explanation:

The work function is the minimum energy required to eject electron's from the surface of the metal. The frequency of photons that are capable of doing this is called the threshold frequency. Given the work function, the threshold frequency can be calculated in the following way

Work function = Planck's constant * frequency

6.56 x 10^-19 J = 6.62607004 × 10-34 m²-kg/s  * f

                      f = 9.90 x 10^14 Hz

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6