atomic structure Flashcards
(24 cards)
a neutral atom has more electrons than
ions
What are atoms
1.smallest particles of an element that have the chemical properties of that element
2.elements are made up of the same type of atoms
what can you infer from the observation that most alpha particles passed straight through the gold foil
atoms are mostly empty space
what can you infer from the observation that a few alpha particles(+) deflected after passing through the gold foil
nucleus of gold atom contains positive charges
what can you infer from the observation that 1 in 10000 alpha particles bounced back from the gold foil
the alpha particles collided with the positively charged nucleus of the gold atom
what does an atom consists of
1.a positively charged nucleus surrounded by negatively charged electrons
2.electrons are orbiting in its respective shells (energy levels)
3. nucleus is tiny in comparison to the size of atom
mass of electron
1/1840
why negatively charged electrons do not get attracted to positively charged nucleus
electrons are orbiting VERY FAST in its respective electron shells
what do valence electrons influence
chemical properties
what do number of neutrons influence
physical properties
chemical reaction only involves
electrons
define isotope
atoms of the same element with same number of protons & electrons but different number of neutrons
nucleon number affects
relative mass and physical properties
why do negatively charged electrons not get attracted to the positively charged nucleus
electrons are orbiting very fast in its respective shells
cations are
metals form positively charged ions (hydrogen and ammonia)
anions are
non metal form negatively charged ions
what happens if too many electrons are added to an atom
strong repulsion when added, might break apart due to strong negative charge
what is an ion
charged particle formed from an atom or a group of atoms by gain or loss of electrons
group of atoms in other words
polyatomic - sulfur sulfate
sharing valence electrons
covalent bond (non metal and non metal)
lose or gain valence electrons
ionic bonds (metal and non metal)
why is argon used to fill tungsten light bulbs but not oxygen
metal serves as fuel for oxygen to cause flame
two valence electrons
duplet configuration
8 valence electrons
octet configuration