I attached the working and the answer to both questions below.
Please note that E = energy, ν = frequency, h = Plank's Constant
<span>The energy of a 4.66 x 10</span>¹⁴<span> Hz wave is
3.088 </span>
× <span>
10</span>
⁻¹⁷ J
Brass is a homogeneous mixture.
In the liquid state, the copper and zinc formed a solution.
They did not separate from each other when the brass solidified.
Thus, brass is a solid solution.
<h2>
Answer: O: 1s22s22p4</h2>
Explanation: In writing the electron configuration for oxygen the first two electrons will go in the 1s orbital. Since 1s can only hold two electrons the next 2 electrons for O go in the 2s orbital. The remaining four electrons will go in the 2p orbital. Therefore the O electron configuration will be 1s22s22p4.
To help, I drew a diagram. This represents an ionic bond between Na and Cl. Na is giving his single electron to Cl, which is indicated by the arrow, to make Cl full with 8 electrons.
