Explain, in terms of sub-atomic particles, why the mass number of a magnesium atom is 24.

On the periodic table, Magnesium has the symbol 12Mg24, where 24 is the mass number and 12 is the atomic number. The atomic number is the number of protons found inside an atom, while the mass number tells us how many neutrons and protons are found in an atom. As the atomic number is 12, we can see we have 12 protons. To calculate the number of neutrons, we do 24-12, which gives us 12. Therefore, the mass number is 24 because Magnesium has 12 protons and 12 neutrons. 

Answered by Matthew N. Chemistry tutor

17261 Views

See similar Chemistry GCSE tutors

Related Chemistry GCSE answers

All answers ▸

Calculate the atom economy for making hydrogen when zinc is reacted with HCL?


What happens to the reactivity of Group 1 elements going down the group and describe why that trend occurs?


Chlorine reacts with potassium bromide to form potassium chloride and bromine. In this reaction chlorine forms chloride ions: Cl2 + 2KBr --> 2KCl + Br2. Explain, using the equation, how you know that chlorine has been reduced.


How does the reactivity of group 7 elements (the halogens) change down the group and why? (A Level)


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2024

Terms & Conditions|Privacy Policy
Cookie Preferences