What is the smallest unit of an element that retains its chemical properties?
Which subatomic particle has a positive charge?
Which particle is found outside the nucleus?
The center of an atom is called the:
Which particle has no electric charge?
The atomic number represents the number of:
The mass number is equal to the sum of:
Which scientist proposed the planetary model of the atom?
Atoms of the same element always have the same number of:
An atom becomes an ion when it:
Elements in the same group of the periodic table have the same number of:
The periodic table is arranged in order of increasing:
Horizontal rows in the periodic table are called:
Vertical columns in the periodic table are called:
Which group contains the noble gases?
Which group contains the alkali metals?
Which element is a halogen?
Which of the following is a metal?
Which element has the atomic number 1?
Which statement about noble gases is correct?
