There can be a lot of meanings for isomers. In this case, we are showing the structural isomers of C₇H₁₆. Based on the chemical formula, CₓH₂ₓ₊₂ it is an alkane. They only differ in the positions of methane branches in the parent carbon chain. Basing on the attached picture, the parent carbon chain is pentane for both isomers. But the methyl branches are on the 2nd & 4th, and 2nd & 3rd carbon for 2,4 - dimethylpentane and 2,3 - dimethylpentane, respectively.
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:
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U-238 has 92 protons, 146 neutrons, and 92 electrons.
Rn-222 has 86 protons, 136 neutrons, and 86 electrons.
U-238 is Uranium 238 and Rn-222 is Radon 222.