Answer:
0.56
Explanation:
From the formula;
0.693/t1/2 = 2.303/t log (Ao/At)
t1/2 = half life of the C-14 = 5730 y
t = time elapsed = 4800 y
At = Activity of C-14 at time t
Ao= Activity of a living C-14 sample
0.693/5730 = 2.303/4800 log (Ao/At)
1.2 * 10^-4 = 4.8 * 10^-4 log (Ao/At)
log (Ao/At) = 1.2 * 10^-4/4.8 * 10^-4
log (Ao/At) = 0.25
Ao/At = Antilog (0.25)
Ao/At = 1.778
Hence;
At/Ao = (1.778)^-1
At/Ao = 0.56
1. Look at the atomic number of the element(located in upper left corner of the element box).This number represent the number of protons of the element.In same of the elements the number of electrons and protons are the same. in other (negative) you have to calculate
2. Look at the atomical mass( located underneath the element, which is a sum of neutrons and protons.Round the mass to the whole number and substract the atomic number. That will be number of neutrons.
Answer:
2Fe⁺³ + Sn₂ → 2Fe⁺² + 2Sn⁺²
Explanation:
A redox reaction occurs between a compound that loses electrons and others that gain an electron. The first is being oxidized, and the other is being reduced.
In this situation, in the compound Fe₂O₃, the iron, has an oxidation number equal to +3, so it's Fe⁺³, and it will gain 1 electron to become Fe⁺². Because it was first dissolved in HCl, we must use the ion at the equation. The other compound Sn₂ will be oxidized to Sn⁺², so it will need to lose 2 electrons.
So, it will be necessary 2 Fe⁺³ for this reaction happen:
2Fe⁺³ + Sn₂ → 2Fe⁺² + 2Sn⁺²
9 Ways to Prevent Rust
Use an Alloy. Many outdoor structures, like this bridge, are made from COR-TEN steel to reduce the effects of rust. ...
Apply Oil. ...
Apply a Dry Coating. ...
Paint the Metal. ...
Store Properly. ...
Galvanize. ...
Blueing. ...
Powder Coating.
.54 km to dm is 5,400 decimeters. Hope this helps, have a BLESSED day! :-)
