Answer:
The frequency
Step-by-step explanation:
The formula for the energy of an electromagnetic wave is
E = hf Thus,
E ∝ f and
f ∝ E
I cannot see the whole equation.Therefore I shall not answer
Answer:
Carbon-13
Explanation:
Carbon have three isotopes. Isotopes are the atoms of the same element which has a different number of neutrons. Carbon has 3 isotopes.
Carbon-12 : 6 electrons I 6 protons I 6 neutrons
Carbon-13 : 6 electrons I 6 protons I 7 neutrons
Carbon-14 : 6 electrons I 6 protons I 8 neutrons
<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>
Answer:
they are composed of water
