For answering for the question, there exists four choices:
1) Na+ + e- -------------- Na
2) Na --------Na+ + e-
3) Cl2 + 2e- ------------ Cl-
4) 2Cl- ---------Cl2 + 2e-
reduction half-reaction general formula is
oxidant + e - or + -------- Product
so in our case the answer is
1) Na+ + e- -------------- Na (exactly balanced)
<span>The </span>elements are arranged<span> in order of increasing atomic number. Vertical columns(called groups) contain </span>elements with similar properties. Horizontal rows called periods elements with<span> the same number of atomic orbitals(That's why Hydrogen and Helium are separated from the rest of the table).
Hope this helps:)</span>
Answer:
it allows us to determine whether objects will float or sink when placed in a liquid or even a gas.
Explanation:
For example, In an oil spill in the ocean, the oil rises to the top because it is less dense than water, creating an oil slick on the surface of the ocean. A Styrofoam cup is less dense than a ceramic cup, so the Styrofoam cup will float in water and the ceramic cup will sink.
Answer:
Equilibrium concentrations of the gases are



Explanation:
We are given that for the equilibrium

Temperature, 
Initial concentration of



We have to find the equilibrium concentration of gases.
After certain time
2x number of moles of reactant reduced and form product
Concentration of



At equilibrium
Equilibrium constant
![K_c=\frac{product}{Reactant}=\frac{[H_2]^2[S_2]}{[H_2S]^2}](https://tex.z-dn.net/?f=K_c%3D%5Cfrac%7Bproduct%7D%7BReactant%7D%3D%5Cfrac%7B%5BH_2%5D%5E2%5BS_2%5D%7D%7B%5BH_2S%5D%5E2%7D)
Substitute the values



By solving we get

Now, equilibrium concentration of gases


