1) The set of quantum numbers (4, 2, 1, +1/2) represent this:
a) first quantum number, 4: is the the main quantum number, it represents the main energy level, if it were the last electron of the atom, that means that the electron belonged to an element in the row number 4 of the periodic table, that is one element between the atomic numbers 19 and 36.
b:second quantum number, 2; is the sub-level of energy, it indicates the kinf (shepe) of orbital, the number 2 means that the orbital is type d.
c. third quantum number, 1: it represents the orientation of the orbital in the space.
d. fourth quantum number, +1/2: it is the spin quantum number, given that two electrons in an atom cannot have the same set of four quantum numbers and two electrons can share the same orbital, when one electron has spin +1/2 the other electron in the same orbital has opposite spin (- 1/2).
2) Set of quantum numbers (4, 1, 1, +1/2).
This electron is in the same main energy level than the previous one (4), but it is in a p orbital (second quantum number = 1), instead of a d orbital, and the orientation is px (third quantum number = 1). The spin is +1/2 the same as the other electron.
M=6.58 g
ρ=0.7899 g/ml
v=m/ρ
v=6.58g/(0.7899g/ml)=8.33 ml
Answer:
2.86 kJ
Explanation:
When a substance is heated and there's no phase change happening, the amount of heat (Q) necessary for the heating can be calculated by:
Q = m*c*ΔT
Where m is the mass, c is the specific heat capacity of the substance, and ΔT is the variation of temperature. So, in this case, m = 53.8 g, c = 1.05 J/g°C, and ΔT = 50.6 K. The temperature variation is the same in °C and K, so:
Q = 53.8*1.05*50.6
Q = 2858.394 J (÷1000)
Q = 2.86 kJ
Okay so we know that pOH + pH = 14, so if pOH is 0.253 the pH would be 13.747.
<span>And pH = -log [H+], so [H+] = 10^(-pH) -->This is just the antillog... </span>
<span>so [H+] = 1.791e-14, which would make sense for the strongly basic solution (so B is the correct answer) </span>
<span>Hope this helps...</span>