Answer:
n = 2.208x10¹⁸ photons
Explanation:
The energy of a photon( an elementary particle) is given by the equation:
E = nxhxf
Where n is the number of photons, h is plank constant (6,62x10⁻³⁴ J.s), and f is the frequency. Knowing that the power level is 0.120mW (1.2x10⁻⁴ W), the energy in J, for a time of 78 min (4680 s)
E = 1.2x10⁻⁴x4680 = 0.5616 J
The frequency of a photon is its velocity ( c= 3x10⁸ m/s) divided by its wavelength, which is 780 nm = 780x10⁻⁹ m
f = 3x10⁸/780x10⁻⁹
f = 3.846x10¹⁴ s⁻¹
Then, the number of photons is:
0.5616 = nx6,62x10⁻³⁴x3.846x10¹⁴
n = 2.208x10¹⁸ photons.
<span>
Phenobarbital is derivative of
Barbituric Acid and Barbituric Acid is derivative of
Urea. (structures shown in Fig below)
Urea has H</span>₂N- group attached to Carbonyl Group (C=O), and such class of comounds conataining H₂N-C=O bond are called as Amides.
Result: So, <span>Phenobarbital belongs to
Amides.</span>
Moles=volume*concentration
=0.1*.83
=.083 Moles of HC2H3O2
Mole ratio between HC2H3O2 and CO2 is 1:1
This means .083 Moles of CO2
Mass =Moles*Rfm of CO2
=.083*(12+16+16)
=3.7grams
Part 1)
Cu- <span>[Ar] 3d¹⁰4s¹ </span><span>atomic number: 29
</span>
<span>O- [He] 2s2 2p<span>4 atomic number:8
</span></span>La- <span>[Xe] 5d¹ 6s² </span><span>atomic number:57
Y- </span><span>[Kr] 4d¹5s² </span><span>atomic number:39
Ba- </span><span>[Xe] 6s² </span><span>atomic number:56
Tl- </span><span>[Xe] 4f¹⁴ 5d¹⁰ 6s² 6p¹ </span><span>atomic number:81
Bi- </span> <span>[Xe] 4f¹⁴ 5d¹⁰ 6s² 6p³ </span>atomic number:83
Part 2)
You are able to this by consulting the periodic table and following this steps:
-Find your atom's atomic number;
<span>-Determine the charge of the atom (these were all uncharged)
</span><span>-Memorize the order of orbitals (s, d, p, d.. and how many electrons they can fit)
</span>-<span>Fill in the orbitals according to the number of electrons in the atom
- </span><span>for long electron configurations, abbreviate with the noble gases</span>
The equation for this reaction is

This means that for every mole of magnesium consumed, 1 mole of magnesium oxide is produced.
So, the answer is <u>0.094</u> moles.