Q = mcΔθ
67.5 = m x 0.45 x (28.5 - 21.5)
M = 67.5 / 3.15
= 21.4 g
Answer:
5. Selenium, because it does not have a stable, half-filled p subshell and adding an electron does not decrease its stability.
Explanation:
Electron affinity is the amount of energy released when an isolated gaseous atom accepts electron to form the corresponding anion.
Selenium:-
The electronic configuration of the element is:-
![[Ar]3d^{10}4s^24p^4](https://tex.z-dn.net/?f=%5BAr%5D3d%5E%7B10%7D4s%5E24p%5E4)
Arsenic:-
The electronic configuration of the element is:-
![[Ar]3d^{10}4s^24p^3](https://tex.z-dn.net/?f=%5BAr%5D3d%5E%7B10%7D4s%5E24p%5E3)
The 4p orbital in case of arsenic is half filled which makes the element having more stability as compared to selenium.
Thus, selenium has higher electron affinity because adding electron does not decrease the stability as in case of arsenic.
Answer:
Radiation
Explanation:
Thermal energy (heat) can be transferred between objects as long as there is a temperature difference between them. However, there needs to be some kind of medium transferring it. There are basically three ways in which the energy is transferred:
1. Conduction - transfer via the direct contact
2. Convection - transfer via the circular movement of fluids or air caused by hotter layers moving upward and colder downwards.
3. Radiation - transfer via the waves from the invisible spectrum of electromagnetic radiation ( ultra-violet, infra-red...)
Frequency is not a type of energy transfer, but a number of times something is occurring in one second. When we say that the frequency is 200Hz it means that something is happening at a rate of 200 times in a second. It's most often used in describing oscillations.
Answer:
D:2
Explanation:
H is hydrogen, and the subscript represents the amount of atoms it has so H2SO is two hydrogens
