Answer:
= 72900 years
Explanation:
- The half-life is the time taken by a radioactive material to decay by half the original amount.
- The half-life of plutonium-239 is 24300 years which means it takes 24300 years to decay by half the original amount.
To calculate the time taken for a mass of 8 kg to decay to 1 kg we use;
New mass = Original mass x (1/2) ^n, where n is the number of half-lives
Therefore;
1 kg = 8 kg × (1/2)^n
1/8 = (1/2)^n
solving for n;
n =3
Therefore;
Time = 3 × 24300 years
= 72900 years
It will, therefore, take 72900 years for 8 kg of plutonium-239 to decay to 1 kg.
Any substance that increases the concentration of 
in aqueous solutions is Arrhenius's acid.
<h3>What are Arrhenius acids?</h3>
Arrhenius define acids as substances with the chemical capacities to increase the concentration of hydrogen ion in aqueous solutions.
Thus, substances like HCl, HNO3, HBr, etc. would be considered an acid. This is because they ionize in aqueous solutions as follows:
HCl ---> + 
More on Arrhenius acids can be found here: brainly.com/question/9936252
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Answer:
D
Explanation:
I think but it is an better attempt than the other guy answer.
A solid that forms and separates from a liquid mixture is a chemical change.
