The number of electrons plus neutrons in ${}_{19}^{40} K^{+}$ is $.....$

Calculate the number of protons,neutrons and electrons in $_{35}^{80}Br$.

Which of the following sets of ions represents a group of isoelectronic ions?

What is the atomic number and the number of electrons in a hydrogen atom (containing $1$ proton) and a sodium atom (containing $11$ protons) respectively?

An element has an atomic weight of $40$ and its electronic configuration is $1s^2 2s^2 2p^6 3s^2 3p^6$. What are its atomic number and the number of neutrons?

The charge on the atom containing $17$ protons,$18$ neutrons and $18$ electrons is