What element has mass number of 4? Chemistry Matter Mass Number 1 Answer anor277 Sep 19, 2016 #""^4He#? Explanation: #""^4He# is common element in the universe, but only a minor constituent in the earth's atmosphere. Answer link Related questions How do you find mass number of an isotope? What does the difference between the mass number and the atomic number tell us? Why is mass number a decimal? What type of radioactive decay produces no change in mass number? How is the mass number written? What is the nucleon number? What is mass number equal to? What does the mass number tell us? How is mass number related to isotopes? How is the atomic mass number changed by gamma decay? See all questions in Mass Number Impact of this question 2404 views around the world You can reuse this answer Creative Commons License