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.
Answer: Chyme
Explain: Chyme passes from the stomach to the small intestine. Further protein digestion takes place in the small intestine.
Answer:
Lonic.an electron will be transferred from potassium to the chlorine atom
Answer:
Bohr thought that electrons orbited the nucleus in circular paths; whereas in the modern view atomic electron structure is more like 3D standing waves. Bohr built upon Rutherford's model of the atom. ... He believed that electrons moved around the nucleus in circular orbits with quantised potential and kinetic energies.
Explanation:
Answer:
Explanation:
Hello,
In this case, since the chemical reaction is:
We can see that hydrochloric acid and magnesium hydroxide are in a 2:1 mole ratio, which means that the neutralization point, we can write:
In such a way, the moles of magnesium hydroxide (molar mass 58.3 g/mol) in 500 mg are:
Next, since the pH of hydrochloric acid is 1.25, the concentration of H⁺ as well as the acid (strong acid) is:
![[H^+]=[HCl]=10^{-pH}=10^{-1.25}=0.0562M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D%5BHCl%5D%3D10%5E%7B-pH%7D%3D10%5E%7B-1.25%7D%3D0.0562M)
Then, since the concentration and the volume define the moles, we can write:
![[HCl]*V_{HCl}=2*n_{Mg(OH)_2}](https://tex.z-dn.net/?f=%5BHCl%5D%2AV_%7BHCl%7D%3D2%2An_%7BMg%28OH%29_2%7D)
Therefore, the neutralized volume turns out:
Best regards.
