Answer is: <span>The general rule of thumb is that the smaller a substance's atoms and the stronger the bonds, the harder the substance will be.
If the distance between atoms is higher, lesser will be attraction between electrons and protons of atoms, smaller distance means stronger atoms attraction.
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Oxygen- atomic number 8
1s² 2s² 2px² 2py¹ 2pz¹
Answer : La carga nuclear efectiva (Zef) es la carga positiva neta experimentada por un electrón en un átomo polielectrónico. El término "efectiva" se usa porque el efecto pantalla de los electrones más cercanos al núcleo evita que los electrones en orbitales superiores experimenten la carga nuclear completa
Explanation:
Boron would have the lower first ionization energy.
Be: 1s2 2s2
B: 1s2 2s2 2p1 -> electron from the p orbital is easier to eject than than electron from the s orbital.
