Answer: Rotation occurs at single bonds that are sigma bonds. Rotational barrier is the amount of activation energy required to covert rotamer to another by rotation that occurs around the sigma bond(C-C single bond). Due to the presence of steric hindrance that is the nonbonding interaction effects the reactivity of ions and molecules, activation energy increases. So the rotational barrier in butenyl cation is high.
When ammonium carbonate is heated it decomposes to give ammonia gas, carbon dioxide gas and water. The equation for the decomposition is;
(NH4)2CO3(s) = 2 NH3 (g) + CO2(g) + H2O(l)
A glowing splint would extinguish almost immediately because of the presence of carbon dioxide. Carbon dioxide does not support burning which is the property that makes it used a s a fighter extinguisher.
Answer: 6.Explanation:1) Aluminum

So each atom of aluminum lost 3 electrons to pass from 0 oxidation state to 3+ oxidation state.
2) Manganesium

So, each ion of Mn(2+) gained 2 electrons pass from 2+ oxidation state to 0.
3) Balance
Multiply aluminum half-reaction (oxidation) by 2 and multiply manganesium half-raction (reduction) by 3:

4) Net equation
Add the two half-equations:

As you see the left side has 2 Al, 3Mn, and 3*2 positive charges.
The right side has 2 Al, 3 Mn, and 2*3 positive charges.
So, the equation is balanced.
5) Count the number of electrons involved.
As you see 2 atoms of aluminum lost 6 electrons (3 each).
That is the answer to the question. 6 electrons will be lost.
Answer: 2.48×10^-17 J
Explanation:
Given the following :
Wavelength = 8nm (8 x 10^-9 m)
Energy(e) of X-ray =?
Energy=[speed of light(c) × planck's constant (h)] ÷ wavelength
Speed of light = 3×10^8m/s
Planck's constant = 6.626×10^-34 Js
Wavelength = 8 x 10^-9 m
Energy = [(3×10^8) * (6.626×10^-34)] / 8 x 10^-9
Energy = [19.878×10^(8-34)] / 8 x 10^-9
Energy = 2.48475 × 10^(-26+9)
Energy = 2.48×10^-17 J