Answer:
Use the activity formula,
T1/2 = 4.468 x 10^9 yr x 365 x 24 x 3600 = 1.409 x 10^17 sec
l = ln(2)/T1/2 = ln(2)/1.409 x 10^17 = 4.91932697 x 10^-18 s-1
DN/Dt = lN, 265 = 4.91932697 x 10^-18 x N
<u><em>N = 5.38 x 10^19 nuclei</em></u>
The answer is/6-(1-2)
Explain why it is not that because it shown
Na₂CrO₄ + PbCl₂ → PbCrO₄ + 2 NaCl
<u>Explanation:</u>
In a double displacement reaction, the reactants which are involved in the reaction exchanging their ions thereby produces 2 new compounds. Here sodium chromate and lead chloride are undergoing double displacement reaction, the ions exchanges their position there by forming sodium chloride and lead chromate. So the double displacement reaction is given as,
Na₂CrO₄ + PbCl₂ → PbCrO₄ + 2 NaCl
Well, all of this we owe it to Bohr who analyzed the atomic emission spectrum of hydrogen and he could probe matematically that it was a result of movement of e- from an especific energy level to a lower one. The understanding of levels of energy took to the development of the atomic theory
Answer:
(a) Potassium 3; phosphorus 1; oxygen 4
(b) Aluminium 3; oxygen 9; hydrogen 9
(c) Iron 10; sulfur 15; oxygen 60
Explanation:
(a) K₃PO₄
In one formula unit of K₃PO₄ , there are three atoms of potassium (K), one atom of phosphorus (P), and four atoms of oxygen (O).
In two formula units there are
Potassium — six atoms
Phosphorus — two atoms
Oxygen — eight atoms
(b) Al(OH)₃
In one formula unit of Al(OH)₃, there is one atom of aluminium (Al), three atoms of O, and three atoms of Hydrogen (H).
In three formula units there are
Aluminium — three atoms
Oxygen — nine atoms
Hydrogen — nine atoms
(c) Fe₂(SO₄)₃
In one formula unit of Fe₂(SO₄)₃, there are two atoms of iron (Fe), three atoms of sulfur (S), and 12 atoms of O.
In five formula units there are
Iron — 10 atoms
Sulfur — 15 atoms
Oxygen — 60 atoms
