An atom is the smallest possible amount of a single element like silicon or carbon.
The animation shows a beryllium atom with four protons and four electrons.
The particles are minute and the atom is mostly empty space.
The electrons are shown as dots but they are more like a cloud of fog.
All familiar everyday objects are made of atoms.
Atoms consist of a small positive nucleus surrounded by a cloud of negative electrons.
Electrically neutral (not charged) matter has equal or balanced amounts of positive nuclei and surrounding negative electrons.
Electrons are arranged around the nucleus in layers or shells. The outer shell is the important one for chemistry, electronics and semiconductor manufacturing.
Last Name Class ID
Q: qNum of last_q
Q ID: Question ID
Score: num correct/num attempts
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