Question

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An elements X who atomic number is 20 mass number is equal to 40 find me and valency metal or nonmetal?
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Answer 1

Answer:

Ca have atomic number 20

&mass number 40

Explanation:

valency is-2

or 12

Answer 2

Answer:

It is given that ,

• Element X whose atomic number = 20
• Mass number = 40

we have to calculate the valency and decide whether it is metal or non metal.

Firstly we find the name of element X

As per given condition the mass of element X is 20 and its mass is 40

So, the elements will be Calcium .

Electronic Configuration of Calcium

Ca = 2,8,8,2

Now, we know that valency of an element is calculated " The number of electrons present in last orbit of an element "

Here, in last orbit of calcium 2 electrons are present .

• So, valency of element X is 2

Since ,2 electrons present in its last orbit so it like to loose 2 electrons from its orbit to gain it stability/noble gas configuration .

And , the elements which loose electrons to gain stability are generally Metal .

• Hence, the element X is a "Metal" .