The element involved in the process of petrification, replacement, and permineralization is silica, were petrification is the combination of 2 types of fossilization, replacement, and permineralization
Permineralization is a way of fossilization in which minerals ( like silica have deposited the fill the empty pores of shells or the hard animal parts). Petrification is a process where the organic material is converted to stone by replacing the original material and the pores with minerals, and Replacement occurs when the original bones or shells dissolve away and is replaced by a different mineral, which occurs along with permineralization, the whole process is called petrification.
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The amount left after 20 years = 154.15 mg
<h3>Further explanation
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The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.
Usually radioactive elements have an unstable atomic nucleus.
The main particles are emitted by radioactive elements so that they generally decay are alpha (α), beta (β) and gamma (γ) particles
The decay formula for isotope :

Then for t=20 years, the amount left :

Answer:
The answer is "3.81041978"
Explanation:


In 1860 





Explanation:
Atomic number , protons and electrons have the same value / their value is same .
But for the neutron there is no specific technique. You have to remember the neutrons of every element
Scirnce uses a method of testing to declare rules or facts. myth and fairy tales have no way of being tested. cats are a physical creature we can see, test, and observe. a mythical idea canny be tested. for example: mermaids cannot be tested as we have none to observe.