The energy of an electron in a hydrogen atom is:
<span>E= (-2.179 x 10 ^-18 J)(1/n^2)
</span>where n is the principle energy level of the electron.
<span>
E= (-2.179 x 10 ^-18 J)(1/4)
</span><span>E= -2.179 x 10 ^-18 J
</span>E = -5.4 <span>x 10 ^-19 J</span>
Answer:
Argon has 8 valence electrons making it non reactive.
Explanation:
Reactive chemicals are store in containers filled with Argon gas because the argon gas is non reactive. This is true because the argon gas has completely filled octet structure.
This can further be explained by writing the electronic configuration of argon.
The electronic configuration of argon is given below:
Ar (18) => 1s² 2s²2p⁶ 3s²3p⁶
Valence electron => 3s²3p⁶ = 2 + 6 = 8
From the above illustration, we can see that the outermost shell (i.e 3s²3p⁶) is having 8 electrons indicating that it is completely filled as the maximum number of electrons any shell can accommodate outside the first shell is 8 electrons. Thus, argon has 8 valence electrons ( i.e electrons in the outermost shell) and hence it is non reactive as the outermost shell is completely filled.
Answer:
177253.125hrs
Explanation:
Given parameters:
Number of hours spend per day on phone = 6.25hrs
Unknown:
Average hours pend by an average American if they lived for 77.7yrs
Solution:
Let us find the number of hours an average American spends on their phone per year;
there are 365days in a year
Number of hours = 365 x 6.25 = 2,281.25hrs
Now, if they lived for 77.7yrs;
They will spend = 77.7 x 2,281.25 = 177253.125hrs
Answer: A convex lens is used to converge ligtht.
Explanation:
A concave lens is a lens that is thicker on the ends than in the middle. As consequence of this, a concave lens diverges (separate) the rays of light. A concave lens is also called diverging lens.
A convex lens is is thicker in the middle than on the ends. As consequence of this, a convex lense converge the parallel rays that pass through it. A convex lens is also called converging lens.