Position of element in periodic table is depend on the electronic configuration of element.
Element with 62 electrons has following electronic configuration:
<span>1s2 2s2 </span>2p6 <span>3s2 </span>3p6 4s2 3d10 4p6 <span>5s2 </span>4d10 5p6 4f6 <span>6s<span>2
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From above electronic configuration, it can be seen that highest value of principal quantum number, where electron is present, is 6. Hence, element belongs to 6th period.
Further, last electron has entered f-orbital, hence it is a f-block element. Position of f-block element is the bottom of periodic table.
Further, there are 6 electrons in f-orbital. Hence, it is the 6th f-block element in 6th period of periodic table.
The alpha particle is the helium nucleus.
The mass of helium nucleus (⁴₂He) is 4u.
The mass of radioactive atom decreases by 4u. Look at the reaction below:
²²³₈₈Ra ---> ⁴₂He + ²¹⁹₈₆Rn
1 mole is equal to 1 moles NaOH, or 39.99711 grams.
Hope this helped
The law that states the volume and absolute temperature of a fixed quantity of gas are directly proportional under constant pressure conditions would be the Charles Law. It <span>is an experimental gas </span>law<span> that describes how gases tend to expand when heated. Hope this answers the question.</span>
<u>Answer:</u> The amount of sample left after 20 years is 288.522 g and after 50 years is 144.26 g
<u>Explanation:</u>
We are given a function that calculates the amount of sample remaining after 't' years, which is:

Putting values in above equation:


Hence, the amount of sample left after 20 years is 288.522 g
Putting values in above equation:


Hence, the amount of sample left after 50 years is 144.26 g