An exponential decay law has the general form: A = Ao * e ^ (-kt) =>
A/Ao = e^(-kt)
Half-life time => A/Ao = 1/2, and t = 4.5 min
=> 1/2 = e^(-k*4.5) => ln(2) = 4.5k => k = ln(2) / 4.5 ≈ 0.154
Now replace the value of k, Ao = 28g and t = 7 min to find how many grams of Thalium-207 will remain:
A = Ao e ^ (-kt) = 28 g * e ^( -0.154 * 7) = 9.5 g
Answer 9.5 g.
I'm not the best with science but I believe the answer is B. Na.
10 electrons
Explanation:
The maximum number of electrons in a single d-subshell is 10 electrons.
The d-sub-orbital used to denote azimuthal or secondary quantum numbers.
The maximum number of electrons in the orbitals of sublevels are:
two electrons in the s-sublevel, it has one orbital
six electrons in the p-sublevel, it has three orbital
ten electrons in the d- sublevel, it has five orbitals
fourteen electrons in the f-sublevel, it has seven orbitals
The maximum number of electrons in an orbital is two.
learn more:
Atomic orbitals brainly.com/question/1832385
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Answer:
The Periodic Table is organized in order of atomic number.
Explanation:
Plz give me brainliest I worked hard on this... thank u in advance.
The concentration of lead nitrate is 3.48 M.
<u>Explanation:</u>
The molarity can be found by dividing moles of sucrose by its volume in litres. We can find the number of moles of sucrose by dividing the given mass by its molar mass. Now we can find the moles as,
Here mass of Pb(NO₃)₂ is 380 g
Molar mass of Pb(NO₃)₂ is 331.2 g/mol
Number of moles = 
= 
= 1.15 moles
Volume in Litres = 330 ml = 0.33 L
Molarity = 
= 3.48 mol/L or 3.48 M
So the concentration of lead nitrate is 3.48 M.
