Atoms and elements

Subdecks (1)

Cards (25)

  • The atom is composed of protons , neutrons and electrons
  • Atoms have a nucleus containing protons and neutrons .
  • Electrons move around the nucleus of the atom
  • All atoms have a nucleus . The nucleus is always positively charged as it contains protons which have a positive charge and neutrons which do not have a charge .
  • The nucleus contains more than 99% of the mass of the atom
  • The total number of protons in an atoms nucleus must be the same as the total electrons in the outer shells
  • Electrons in atoms always orbit the nucleus and have a negative charge
  • Atoms are always neutral because the positive charge from protons cancels out the negative charge from electrons
  • The nucleus of a atom of an element may contain different number neutrons .
  • The diameter of the atom is about 10 to the power of -10 . Whereas the diameter of the nucleus is much smaller at around 10 to the power of -15
  • An electron will move from a lower to a higher orbit if it absorbs electromagnetic radiation .
  • An electron will move from a higher to lower obit if it emits electromagnetic radiation.
  • Is an image of an electron absorbing electromagnetic radiation
  • Is an image of an atom if it emits electromagnetic radiation
  • The atom is the smallest part of an element that can exist
  • All substances are made of atoms
  • Atoms are very small with a radius of 0.1 nm
  • An element contains only one type of atom
  • Elements are found on the periodic table
  • There are about 100 elements.
  • An isotope is the same element with a different number of nuetrons