Answer:
A=emitted B=absorbed
Explanation:
If an electron drops down from n=2 to n=1 energy is emitted, and if the electron moves up from n=1 to n=2 energy is absorbed. The amount of energy that is either absorbed or emitted is called quanta.
There are several elements in the Periodic Table that are both malleable and good conductors of electricity and even heat. The Alkali metals such as potassium and sodium from Group 1 of the Periodic Table are very good conductors of electricity and are also pliant and malleable. From the group of Transition metals iron, copper, silver and gold are instances of all the 38 metals of this group that fulfil the conditions of being conductors and malleable. Some metals such as tin, lead, thallium, and aluminium are instances of elements that are malleable and can conduct electricity in the solid form. These elements belong to the Metalloids group in the Periodic Table.
The net ionic equation for the neutralization reaction involving equal molar amount amount of HNo3 and KoH is
H^+ + OH^- = H2O (l)
explanation
write the chemical equation
HNO3 (aq) + KOH(aq) = KNO3(aq) +H2O (l)
ionic eequation
H^+(aq) + NO3^- (aq) + K^+9aq) OH^-(aq) = K^+ (aq) + NO3^-(aq) + H2O(l)
cancel the spectator ions( ions which does not take place in equation ) for this case is NO3^- and No3^-
thus the net ionic is
H^+(aq) + OH^- (aq) = H2O(l)
Which device is designed to produce mechanical energy?
Well, mechanical energy is the sum of potential and kinetic energy. Kinetic energy is a unit of energy in which is the reason why an object does movement, while potential energy is another unit of energy in which is the reason why an object doesn't move, or stops. While you can stop a fan or a lamp, it isn't automatic. It's manually. So the answer is (4) an oven because mechanical energy happens automatically, not manually, or for a greater reason.
Bc in the old times there were no phone and social media like now so that’s why it changed a lot the technology