Half life is defined as the amount of time it takes for a radioactive material to divide itself into half after radioactive decay process. So basically, after the prescribed half-life, what transforms to another material is 1/2 of the original and what is left is 1/2 as well. In this case, the formula applicable is
ln N/No = -kt
where N represents the masses before and after decay, t is the time elapsed and k is the decay rate constant.
Substituting,
ln 10/40 = -k*20
-k = <span>-0.0693
To find t1/2 or half life, then
ln 0.5 = -k*t1/2
t1/2 = ln 0.5 / 0.0693 = 0.1 minutes
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To balance the scale, you need to have the same weight as both sides. So you need total 10 grams to balance which is also ten 1 gram weight.
Answer: True
Explanation:
The statement that "A double replacement reaction is a chemical reaction between two ionic compounds in which ions are interchanged to form two new compounds" is true.
We should also note that a double replacement reaction can also be referred to as a metathesis reaction. In such cases, the ions of the compounds involved will be exchanged in order for a new compound to be formed. An example of a metathesis reaction is:
FeSO4 + CuCl2 = FeCl2 + CuSO4
Question: Why do the inner walls of a vacuum flask have a silver coating?
Answer: it prevents heat transfer by radiation and the walls stops heat entering or leaving the flask by conduction.
Explanation: so as you can see all these parts play a roll to keep ceartain things safe to keep things in and what needs to go out it lets it go out
question answered by
(jacemorris04)