А5. В ряду Ве-В-С-N происходит
1) увеличение радиуса атомов
2) уменьшение силы притяжения валентных электронов к ядру
3) увеличение электроотрицательности
4) уменьшение числа валентных электронов
According to the Moseley's law, which states that the atomic number of an element is directly proportional to its atomic radius, the trend in A5 is due to the increase in the atomic number of the elements. The first two trends, namely the increase in the atomic radius and the decrease in the force of attraction of valence electrons to the nucleus, are mainly caused by the increase in the number of protons, which outweighs the increase in the number of electrons. This leads to an increase in the repulsive forces between the electrons and a decrease in the attractive forces between the nucleus and the electrons. As for the increase in electronegativity, it is caused by the increase in the number of valence electrons, which leads to a higher probability of forming covalent bonds and thus a higher tendency to attract electrons. To decrease the number of valence electrons, elements tend to use their valence electrons to form compounds and become more stable. So in order to decrease all the trends observed in A5, all the elements need to do is to join forces and share their valence electrons with each other, thus achieving a more stable state and reducing the competition for electrons.
