subatomic particles
what are the subatomic particles? what are their charges?
protons (positive), neutrons (neutral), electrons (negative)
nitrogen has 7 protons, 7 neutrons, and 7 electrons -- what is the atomic mass?
12 amu
group 18 elements are called this. list at least one property of this family.
noble gasses
properties:
- very stable and unreactive
- gas at room temperature
- glow in electric lights
what is ionization energy? in what ways does it increase?
energy required to remove electrons
left to right & down to up
where are each of the subatomic particles found? write and model your answer.
protons (in the nucleus), neutrons (in the nucleus), electrons (in the electron orbit)
how many protons does tin have?
50 protons
the family of halogens are in which group number? list at least oner property of this family.
group 17
properties:
- very reactive
- exist as diatomic molecules
- often form salts when combined with metals
between O (oxygen) and S (sulfur), which has higher electronegativity? why?
O (oxygen) because more protons pulling
what do each of the subatomic particles do for an atom?
protons = atomic number & atomic mass/weight
neutrons = atomic mass/weight
electrons = atomic properties & reactivity
lead has an atomic weight of 207 and an atomic number of 82 -- how many protons does lead have?
82 protons
group 1 elements are called this. list at least one property of this family
alkali metals
properties:
- very reactive
- soft metals
- shiny, but dull quick
what is electron affinity? in what ways does it decrease?
energy change when an atom gains electrons
right to left & up to down
name the fermions that make up subatomic particles and tell me what makes what.
quarks (protons and neutrons), leptons (electrons)
the atomic mass of calcium is 40 -- how many neutrons does it have?
20 neutrons
metalloids are in the middle of __________ and __________. list the atomic numbers of the elements in this family and at least one property of this family.
metals and non-metals. 5, 14, 32, 33, 51, 52, 84
properties:
- can behave as metals or nonmetals depending on the reaction
- semiconductors
across a period (left to right), does atomic radius/mass increase or decrease? down a group (top to bottom), does atomic radius/mass increase or decrease? why?
decrease (less orbits)
increase (less protons = electrons pulled)
describe the building-block hierarchy and their subunits:
fermions (____, ____) → ? (____, ____, ____) → ? → ?/?
fermions (quarks, leptons) → subatomic particles (protons, neutrons, electrons) → atoms → molecules/compounds
calcium has 20 neutrons, 20 electrons, an atomic number of 20, and an atomic weight of 40. how many protons does calcium have?
20 protons
why do elements in the same group react similarly? why do elements in the same period react similarly?
same number of valence electrons / same number of electron shells
across a period (left to right), does reactivity for metals increase or decrease? down a group (top to bottom), does reactivity for non-metals increase or decrease? why?
decrease (less likely to lose electrons and form positive ions)
decrease (tendency to gain electrons decreases)