Answer:
Excited state of an electron is the state attained by an electron after it has absorbed energy and it moves further from the nucleus.
an electron is at higher energy when excited and at lower energy when at ground state.
an excited electron is less stable due to the decrease in the nuclear force of attraction and the grounded electron is more stable due to it's close distance to the nucleus.
The reason people describe water as a universal solvent is because it dissolves almost anything.
<h3>Answer:</h3>
Strontium (Sr)
<h3>Explanation:</h3>
The condition given in statement is the presence of two valence electron. Hence, first we found the electronic configuration of given atoms as follow;
Rubidium [Kr] 5s¹
Strontium [Kr] 5s²
Zirconium [Kr] 4d² 5s²
Silver [Kr] 4d¹⁰ 5s¹
From above configurations it is cleared that only Strontium and Zirconium has two electrons in its valence shell.
We also know that s-block elements are more reactive than transition elements due to less shielding effect in transition elements hence, making it difficult for transition metals to loose electrons as compared to s-block elements. Therefore, we can conclude that Strontium present in s-block with two valence electrons is the correct answer.
It is a nuclear reaction since a change has occurred in the nucleus. In nuclear reactions the particles in the nucleus are changed and one element is transformed into another element when particles in the nucleus gained are lost. Unlike chemical reactions which involve the electrons in an atom, nuclear reaction involve the nucleus. A nuclear reaction may be a nuclear fission or nuclear fusion; An example of nuclear reaction is where two isotopes of hydrogen (tritium and deuterium) are fused together under high pressure and temperature, to form a more stable atom of helium. This is an example of nuclear fusion reaction.
The answer is -11.2 fahrenheit.