<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.
Elements that belong to the same period which is seen horizontally in the periodic table have different properties. Elements with similar properties are seen in columns or groups. Elements in the same period have similar principal quantum number and belong to the same principal shell. Hence the answer is that t<span>hey have different properties that repeat across the next period</span>.
different parts of the sum rotate at different rates
a thing, especially a trend or fact, that indicates the state or level of something.
Answer:
Its color.
Explanation:
The color of ice is white and we know that white color is a good reflector while black color is a good absorbent. So that's why people in warm countries uses white clothes due to its reflecting property uses black clothes in winter due to its absorbing property. So due to white color of the ice sheet, more solar radiations are reflected back into the atmosphere after striking.
