proton - particle with a positive charge, neutron - particle with a neutral charge, electron - particle with a negative charge, nucleus - center of an atom, atom - smallest unit of matter, element - substance made of 1 type of atom, matter - anything that takes up space or has mass,

लीडरबोर्ड

दृश्य शैली

विकल्प

टेम्पलेट स्विच करें

ऑटो-सेव पुनःस्थापित करें: ?