chapter 2 Flashcards
what subatomic particles does an atoms nucleus consist of ?
protons and neutrons
what subatomic particle occupies the region outside the nucleus arranged in shells?
electrons
atoms and their subatomic particle have tiny masses instead of working in grams, what do chemists use compare the masses of subatomic particles?
relative mass
what does a proton have virtually the same mass as?
neutron
an electron has a negligible mass what is is in terms of a proton?
1/1836th the mass of a proton
accurate measurements show that neutrons have a slightly greater mass than a proton by a factor of what? however its so close to 1 chemists usually assume equal mass.
1.001375
what charge does a proton have?
positive
what charge does an electron have?
negative
what is the charge on a proton compared to the charge of an electron?
equal but opposite the charges balance
what charge does a neutron have?
no charge
what’s the actual charge of a proton and electron? buts its much easier to use relative charges of 1+ for a proton 1- for an electron.
+1.60217733 x 10-19C, -1.60217733 x 10-19C
where is nearly all the atoms mass?
in the nucleus
what to atoms contain the same number of?
protons and electrons
what the abbreviation, relative charge, and relative mass of a proton?
p*+, 1+, 1
what the abbreviation, relative charge, and relative mass of a neutron?
n, 0, 1
what the abbreviation, relative charge, and relative mass of a electron?
e*-, 1-, 1/1836
what is the total positive charge from protons cancelled by?
total negative charge of electrons
what is the overall charge of an atom?
0- an atom is neutral
neutrons can be thought as providing the glue that hold the nucleus despite what?
the electrostatic repulsion between its positively charged protons
most atoms contain the same number or slightly more of what?
neutrons than protons
as the nucleus gets larger more and more of what are needed.
neutrons
what identifies the element?
the number of protons
as of 2014, the existence of how many elements have been confirmed not including those that have been tentatively reported?
114
every atom of the same element contains the same number of what?
protons
different elements contain atoms that have different numbers of what?
protons
what order does the periodic table list elements?
by the number of protons in the nucleus
what’s another way to say proton number(number of protons)?
atomic number
what’s an isotope?
atoms of the same element with different numbers of neutrons and different masses
what are most elements made from?
mixture of isotopes
what is the mass number?
number of protons + number of neutrons
what is the atomic number?
number of protons
what do chemical reactions involve?
electrons surrounding the nucleus
different isotopes of the same element have the same number of what?
protons and electrons
what does the number of neutrons have no effect on?
the reactions of an element
different isotope of an element react..
in the same way
where may there be a small difference in higher-mass isotopes?
higher melting point, boiling point, and density
what isotope of hydrogen is in heavy water?
2, 1 H
what is the 2,1 hydrogen isotope often referred to as and given the symbol of?
deuterium, D
what the formula of heavy water?
D2O
what’s the melting point of heavy water?
3.8 d.c
what is the boiling point of heavy water?
101.40 d.c.
what’s the density of heavy water?
1.11 d.c.
what’s the density of heavy water?
1.11 d.c.
what gives heavy water its name?
it’s greater density
what gives heavy water its name?
it’s greater density
if all water was heavy water what would you see far more often?
ice as the water freezes at a higher temperature
what is the third isotope of water called?
tritium, T
how many neutrons does tritium contain?
two
tritium forms an oxide called..
super-heavy water
what’s the relative mass of H2O, D2O and T20
1.2 and 3
how does the melting point, boiling point, and density of T2O differ from H2O and D2O
higher melting point, higher boiling point and, larger density
what’s an ion?
a charged atom, the number of electrons differ from the number of protons
what’s a cations?
a positive ion with fewer electrons then protons.
what’s an anions?
a negative ion with more electrons then protons
what do ions and atoms have the same number of and a different number of?
same number of protons different number of electrons
