How Many Neutrons Does Promethium (Pm) Have?

Answer:

promethium (Pm) has 86 neutrons for this isotope.

Hello, chemistry lover! today I am going to help you to find out how many neutrons promethium (Pm) have in just 3 steps.

To find out the number of neutrons for promethium (Pm),we have to have knowledge about atomic number,atomic mass and mass number of promethium (Pm).

.Click picture to see clearly.

Step-1:

●The atomic number of  promethium (Pm)  is the number of protons in promethium (Pm)'s nucleus.

●The atomic mass of  promethium (Pm)   is the average number of protons plus neutrons of all the isotopes of promethium (Pm) .

●The masss number of  promethium (Pm)  is the number of protons plus neutrons of a specific isotope of  promethium (Pm)   .

Step-2:

We need to convert atomic mass of  promethium (Pm)  to mass number of  promethium (Pm) by rounding if necessary (In case of fraction) .

From periodic table,

●Atomic number of  promethium (Pm) is 61.

●Atomic mass of  promethium (Pm) is 147

●To find out mass number,we need to round 147 to a whole number.

So,by rounding,we are getting the mass number of promethium (Pm).The mass number of promethium (Pm) (we are getting) is 147.

Step-3:

By the difference between mass number and atomic
number of promethium (Pm),we get the number of neutrons in promethium (Pm).

●Number of neutrons=147-61=86

In another way,

●Mass number=Protons +Neutrons

Or,147 =61+Neutrons

Or,142-61=Neutrons

Therefore,

Neutrons=86

Therefore,the number of neutrons in promethium (Pm) is 86 here for this isotope.Remember that neutrons are present in the nucleous of promethium (Pm) and it's charge is zero.

●Number of protons in promethium (Pm) is 61.Protons are present in the nucleus of promethium (Pm) .

● Number of electrons in promethium (Pm) is 61.Remember that number of electron equals to proton in a neutral atom.Eletrons are present outside of nucleus of promethium (Pm) .

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