Atomic Concepts
All atoms of oxygen have the same:
1) mass #
2) atomic #
3) # of protons plus neutrons
4) # of neutrons plus electrons
2
Answers may vary
Which has a lower freezing point; distilled water or a 0.5 M NaCl(aq)?
NaCl
This phase change goes directly from solid to gas, skipping the liquid phase.
sublimation
What is the oxidation number of Li+?
+1
What subatomic particle has a charge that is equal in magnitude to a proton, but opposite sign?
electron
State, in terms of valence electrons, why boron and oxygen have different chemical properties.
They have a different # of valence electrons (they are in different groups)
Write the molecular formula of an electrolyte that is found in your periodic table.
any acid or base (or ionic compound)
Which sample of matter cannot be broken down by a chemical change; water, butane, niobium, or ammonia?
Niobium
In a redox equation, 5 moles of electrons are lost from one species. How many electrons are gained by the species reduced?
5 moles
How many electrons in Li-6?
3
Which element has five valence electrons in each of its atoms in the ground state; Se, Kr, As, or Ga?
As
According to one acid-base theory, an acid is a H+ _________ (donor/acceptor)
donor
Sort the following terms into two columns; physical changes and chemical changes
sublimation, decomposition, condensation, deposition, synthesis, combustion, vaporization
Physical: sublimation, condensation, deposition, vaporization
Chemical: decomposition, synthesis, combustion
Identify the subatomic particles that flow through the wire as an electrochemical cell operates.
electrons
List one conclusion from the gold foil experiment.
Atoms are mostly empty space OR
Atoms have a dense, positively charged core (nucleus)
Two forms of solid carbon, diamond and graphite, at STP, have the same/different crystal structure and the same/different properties
different/different
A chemical reaction is at equilibrium. What do you know about the rates of the forward and reverse reactions?
The rates are equal
As water is melting, describe what's happening in terms of potential energy and kinetic energy.
PE is increasing, KE is constant
In an electrolytic cell, ________ energy is converted to _________ energy
electrical energy is converted to chemical energy
The bright-line spectrum of an element is produced when excited-state electrons absorb/emit energy and move to higher/lower energy states
emit/lower
As elements are considered in order of increasing atomic number across a period, the atomic radius increases/decreases
Decreases
Draw the structural formula for CH3CH2COOCH2CH3
show structure
Solid aluminum has a specifi c heat capacity of 0.90 J/g•K. How many joules of heat are absorbed to raise the temperature of 14.0 grams of aluminum from 300. K to 360. K?
didn't do it
Which is the most easily oxidized; Ba, Al, Fe, or Pb?
Ba