Answer:
3.4x10⁻¹⁹J is the energy of the photon
Explanation:
To find the energy of a photon from its frequency we must use the equation:
E = hf
<em>Where E is the energy of the photon in J, our incognite</em>
<em>h is Planck's constant = 6.6262x10⁻³⁴Js</em>
<em>And f is the frequency = 5.2x10¹⁴Hz = 5.2x10¹⁴s⁻¹</em>
<em />
Replacing:
E = 6.6262x10⁻³⁴Js*5.2x10¹⁴s⁻¹
E = 3.4x10⁻¹⁹J is the energy of the photon
<em />
Answer: C
Explanation: Picture attached.
I think, either 100 degrees celsius (as of water)
56 degrees celsius (acid)
or 118.1 degrees celsius (acetone)
<span>PbO
Let's look at each of the 4 compounds and see what's needed.
PbO.
* Oxygen has a valance shell that's missing 2 electrons and wants to get those 2 elections. Lead donates them, so you have a Lead (II) ions. This is a correct choice.
PbCl4
* Chlorine wants to grab 1 electron to fill it's valance shell and Lead donates that election. However, there's 4 chlorine atoms and every one of them wants and electron, and lead is donating all 4 of the desired electrons making the Lead (IV) ion. So this is a bad choice.
Pb2O
* Oxygen still wants 2 electrons and gets them from the lead. But there's 2 lead atoms and each of them donates 1 election making for 2 Lead(I) ions. So this too is a bad choice.
Pb2S
* Sulfur is in the same column of the periodic table as oxygen and if this compound were to exist would have similar properties as Pb2O and would have Lead(I) ions. So this is a bad choice.</span>
Explanation:
most of the x-rays are absorbed in thermosphere of earth's atmosphere
