Answer:
frequency = 8.22 x 10¹⁴ s⁻¹
Explanation:
An electron's positional potential energy while in a given principle quantum energy level is given by Eₙ = - A/n² and A = constant = 2.18 x 10⁻¹⁸j. So to remove an electron from the valence level of Boron (₅B), energy need be added to promote the electron from n = 2 to n = ∞. That is, ΔE(ionization) = E(n=∞) - E(n=2) = (-A/(∞)²) - (-A/(2)²) = [2.18 x 10⁻¹⁸j/4] joules = 5.45 x 10⁻¹⁹ joules.
The frequency (f) of the wave ionization energy can then be determined from the expression ΔE(izn) = h·f; h = Planck's Constant = 6.63 x 10⁻³⁴j·s. That is:
ΔE(izn) = h·f => f = ΔE(izn)/h = 5.45 x 10⁻¹⁹ j/6.63 x 10⁻³⁴ j·s = 8.22 x 10¹⁴ s⁻¹
Answer:
6
Explanation:
As , 2H2 + O2 = 2H2O
with 6 H2, 4O2 is excess.
H2O molecules formed = 6
Answer:
1.5 of mag 1 phos 1 oxygen
Explanation:
hope this helps well sorry i don't really know lol i tried
Answer: The final concentration when 5 ml of a 2.5M copper sulphate solution is diluted to 750 ml is 0.017 M
Explanation:
According to the dilution law,
where,
= molarity of stock 
solution = 2.5 M
= volume of stock solution = 5 ml
= molarity of diluted solution = ?
= volume of diluted solution = 750 ml
Putting in the values we get:
Therefore the final concentration when 5 ml of a 2.5M copper sulphate solution is diluted to 750 ml is 0.017 M
Th correct answer is option C. Calling can be hazardous because it also attracts parasites and predators.
The mating call is used by the males to attract females for sexual reproduction. By using vocal sounds males are not only making themselves attractive to females, they are also making themselves vulnerable to predators.
Thus the mating call can have a disastrous effect on the survival of the species.
