The vertical columns in the periodic table are called _____, whereas the horizontal rows are referred to as _____.

Which of the following is a true statement regarding the atomic number of an element?

Which one of the following changes when you change the number of neutrons in the nucleus of an element?

Which of the following appropriately represents the subatomic particles in the given image of an atom?

Which one of the following pairs will contain the same number of molecules?

Noble gases have full electron shells, while halogens readily gain an electron to fill their outermost shell. Which of the following statements is therefore true?

Select the correct term for elements that are rarely found on the earth