Free help with homework

Why join Brainly?

  • ask questions about your assignment
  • get answers with explanations
  • find similar questions

To calculete the mass number of the chemival element with,Z=15,knowing that the,number is higher than electron on proton? very nice please !!!



Z=15 means that element is phosphorus . and it contains 15 electrons and 15 protons. and its atomic weight is 31.
0 0 0

This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
Z = 15 means there are 15 protons in the element
As number of proton is equal to number of electrons, there are 15 electrons.
From z = 15, you also know that it is Phosphorus. 
But z= 15 does not provide information about its atomic mass(mass number). You have to know the number of neutrons init. Number of neutrons is 16 and hence the mass number is (15+16) = 31.
0 0 0
The Brain
  • The Brain
  • Helper
Not sure about the answer?
Learn more with Brainly!
Having trouble with your homework?
Get free help!
  • 80% of questions are answered in under 10 minutes
  • Answers come with explanations, so that you can learn
  • Answer quality is ensured by our experts