Question

1. Какое из утверждений неверно:а) атомы элементов 2А группы содержат два электрона на внешнем энергетическом уровне б) радиус атома в подгруппе увеличивается от бериллия к радиюв) восстановительные свойства атомов ослабевают от радия к бериллиюг) если у атома на внешнем энергетическом уровне 2 электрона,данный элемент находится во 2А группе?

Answer 1

Неверно Г, кажется. Так как такие элементы могут находиться в группе 2В. Вроде бы...

Answer 2

The Incorrect Statement:

The incorrect statement is d) если у атома на внешнем энергетическом уровне 2 электрона, данный элемент находится во 2А группе.

Explanation:

The elements in the 2A group (Group 2) of the periodic table, also known as the alkaline earth metals, have two electrons in their outer energy level. This is true for all elements in this group, including beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra) [[1]].

However, the statement in option d) is incorrect. Just because an atom has two electrons in its outer energy level does not mean that it belongs to the 2A group. The group number is determined by the number of valence electrons, which are the electrons in the outermost energy level. In the case of the 2A group, the elements have two valence electrons.

For example, helium (He) also has two electrons in its outer energy level, but it belongs to the 8A group (Group 18) because it has a full outer energy level. Similarly, hydrogen (H) has one electron in its outer energy level but belongs to the 1A group (Group 1) because it has one valence electron.

Therefore, the correct statement is that the elements in the 2A group have two valence electrons, not just two electrons in their outer energy level.