an atom has 14 protons and 13 neutrons what is its mass number?

Question

Could you explain to me how you know the answer thanks.

thanks for the help i'm starting to understand this now. I just had one more question. an atom has 15 protons and a mass of 31 so the atomic number is 15 and it has 16 neutrons right? it asks what the element is, I think its phosphorus because its atomic number is 15 is that right?

also how many neutrons can be found in the nucleus of an atom chlorine-37? I dont know how to get this answer could you explain this please.
thanks

Answer 1

# electrons = #protons

atomic weight = protons + neutrons

so:

14 + 13 = 27

Answer 2

(27:) WELL let me tell you that The atomic weight is basically a measurement of the total number of particles in an atom's nucleus. In reality, it isn't that clean cut. The atomic weight is actually a weighted average of all of the naturally occurring isotopes of an element relative to the mass of carbon-12. Didn't understand that? Doesn't matter. All you really need to find is something called the mass number. Unfortunately, the mass number isn't listed on the Table of Elements. Happily, to find the mass number, all you need to do is round the atomic weight to the nearest whole number. In our example, krypton's mass number is 84 since its atomic weight, 83.80, rounds up to 84.

The mass number is a count of the number of particles in an atom's nucleus. Remember that the nucleus is made up of protons and neutrons. So, if we want, we can write:

Mass Number = (Number of Protons) + (Number of Neutrons)

For krypton, this equation becomes:

84 = (Number of Protons) + (Number of Neutrons)

If we only knew how many protons krypton has, we could figure out how many neutrons it has. Wait a minute... We do know how many protons krypton has! We did that back in Step 2! The atomic number (36) is the number of protons in krypton. Putting this into the equation, we get:

84 = 36 + (Number of Neutrons)

What number added to 36 makes 84? Hopefully, you said 48. That is the number of neutrons in an atom of krypton.

The interesting thing here is that adding or removing neutrons from an atom does not create a different element. Rather, it creates a heavier or lighter version of that element. These different versions are called isotopes and most elements are actually a mixture of different isotopes.

If you could grab atoms of krypton and count the number of neutrons each one had, you would find that most would have 48, others would have 47, some would have 50, some others would have 46, a few would have 44 and a very few would have 42. You would count different numbers of neutrons because krypton is a mixture of six isotopes.

Answer 3

27

The mass number or weight is the sum total of all of the inner nucliec particles: protons + neutrons = Mass

The atomic number is the number of protons, so the atomic number of that atom would be 14 which, in the real periodic table of elements is Si or Silicon, and it has 14 neutrons, so your 'atom' is probably an isotope of Silicon.

Answer 4

27

Answer 5

The total number of protons and electrons presnt in an element is called its mass number.

so mass number is equal to=number of protons + electrons
so mass number=14 + 13
= 27
similarly with mass number and protons or electrons you can find electrons or protons respectively

Answer 6

mass number is the sum of the number of protons and neutrons
your mass number is 27