The isotopes are elements with the same number of protons but different number of neutrons.
Boron atomic number is 5. That is the number of protons.
The natural occurring isotopes of boron contain 5 or 6 neutrons. Other, non stable isotopes, contain from 1 to 16 neutrons.
The answer to your question is position and number of chemical shifts give information about the structure of a organic molecule. Chemical shift describes the relative positions of the resonances in an NMR spectrum. It is also the position on the δ scale (ppm - parts per million) where the peak occurs.
Answer: Be= 2, C =4, Li = 1 and B=3
Explanation:
The valence shell can be define as the outermost shell of an atom that contains the valence electrons.
Beryllium (Be), electronic configuration; 1s2 2s2, = 2 electrons in its valence shell.
Carbon (C), electronic configuration; 1s2 2s2 2p2, = 4 electrons in its valence shell.
Lithium (Li), electronic configuration; 1s2 2s1 = 1 electron in its valence shell.
Boron (B) , electronic configuration; 1s2 2s2 2p1 = 3 electron in its valence shell.
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