Quantum Mechanical model (as per my knowledge)
It’s C I think and I’m not sure
Answer:
The radioactive isotopes within these brains typically record the ages of the grains-not the time when the sedimentary rock was formed, making it difficult to date using radiometric dating. The half-life of U-235 is 704 million years.
Explanation:
hope this helps but if i'm wrong then i'm sorry..
Answer:
Element
Explanation:
Each different kind of atom represents an atom. Elements like atoms are considered to be distinct substances that cannot be split into simpler substances. Such substances are known to be made up of just one kind of atom.
Like an atom, elements are made up of protons, neutrons and electrons. Both the protons and neutrons are found in the nucleus of the atom.
The percentage by mass of water in Na2CO3.10H2O from the calculation is 62.9%
<h3>What is percentage by mass?</h3>
The term percentage by mass refers to the amount of a particular moiety by mass in a molecule.
In this case, we know that the molar mass of Na2CO3.10H2O is 286 g/mol the molar mass of the 10 moles of water is 180 g/mol hence the percentage by mass of water in the compound is; 180 g/mol /286 g/mol * 100/1 = 62.9%
Learn more about percentage by mass: brainly.com/question/16885872
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