D. through measuring and observing !
it exists as atom or ion but not as sodium molecule. So there is no any sodium sodium bonding between two sodium atoms. Sodium combines with other element or group to form compounds of sodium like sodium chloride ,sodium carbonate ,sodium sulphate etc. Sodium has symbol Na and its atomic no. is 11 .
Because pure silicon is a perfect semiconductor.
For room temperature, it rarely conducts, you can search for the threshold temperature, the characteristic equation is fairly complicated.
Ca, V, Cu, Kr
Remember a period is a the horizontal rows in the Periodic Table.
Hello beth what exactly is the question here !!
