Which atom has the same number of electrons as an ammonium ion?
HCN has been detected in interstellar gas. Which molecule contains the same total number of valence shell (outer shell) electrons as HCN?
An element M has an atomic mass of 19 and atomic number 9; its ion is represented by
Which atom has the same number of electrons as the hydroxide ion, OH-?
How many electrons, protons, and neutrons are present in the element represented by the symbol with atomic number 21 and mass number 43?
What is the total number of protons, neutrons, and electrons present in an ammonium ion with a relative formula mass of 21?
An element has an atomic number of 11 and a mass number of 24. What does the nucleus contain?
What is the number of electrons in (24,12)Mg2+ ?
The ion Y3- contains 18 electrons and has a mass number of 31. How many protons and neutrons does Y3- contain?
An element X has an atomic mass of 39 and an atomic number of 19; its ion is represented by
Sodium azide, NaN3, consists of sodium ions and azide ions. What are the numbers of electrons in the sodium ion and the azide ion respectively?
Which statement about iodine-131 (53/131 I) is correct?
