Chemistry 1 Flashcards
Effect on equilibrium:
Changing TEMP if the rxn is EXOthermic
CHANGES Keq
shifts equilibrium
increase temp=
- shifts left
- Keq decreases
decrease temp=
shifts right
Keq increases
PT trends: trend for most metallic/gives up VE easiest
to the left and down=most metallic & most willing to give up its ve
- Define “Work Function”
- bombarding metals with (sufficient) energy
causes valence electrons to be ejected
If you add MORE energy than Work Energy ( “ φ “), what happens?
- the energy is transferred
…into the KE of the ejected valence electron
Periodic Table
- Where is the S-BLOCK?
the first 2 columns
WORK FUNCTION
- Give the formula
KE=hf - φ
or KE=E - φ
(since E=hf)
Think of NEUTRONS as:
PROTON + ELECTRON
How do you calculate Percent (%) Mass?
Percent % Mass=
mass of ONE element / TOTAL mass of cpd
x 100%
Think of METALS as:
LARGER atoms with LOOSELY held electrons
What is “Theoretical Yield?”
amt of product (in g) that would be produced IF rxn ran to 100% completion
Elements in the same FAMILY have…
similar CHEMICAL and PHYSICAL properties
Finding the LIMITING REAGENT
- What 2 things MUST you do BEFORE you can go about finding the limiting reagent?
- Once these 2 things are done, what are the 2 steps to finding the limiting reagent?
You MUST:
- Have a balanced equation
- Convert to moles first
STEPS:
- Compare # of moles YOU have to # moles REQUIRED TO RUN THE REACTION
- as indicated by coefficients
- The reactant you run out of FIRST:
= the limiting reagent
- Metals like to ____ e’s and form___
- Metals are (3 physical properties)
- What are metals’ conductive properties?
Metals like to LOSE ELECTRONS and form CATIONS
Metals are:
- lustrous
- ductile
- malleable
Metals are good conductors of heat AND electricity
What qualifies something as a good “Electrolyte?”
-
Covalent cpds that dissociate 100% in water are GOOD electrolytes
- ex: SA’s & SB’s are good electrolytes
ALL IONIC compounds that are water soluble are GOOD electrolytes
Recognizing Compounds:
Sulfate
SO42-
Yield is a function of what 2 things?
Addition of what NEVER increases yield?
- Yield is a function of: R
- Reactants
- Equilibrium
NOT Rate!
- Adding a catalyst with increase rate, but not yield
Define “Radioactive Decay”
the process by which UNSTABLE atoms change their chemical composition over time
- Element symbols
- Z=
- Atomic NUMBER
- (number of protons)
Will NaCl or KCl have a higher CONDOSITY?
Why?
KCl
because K is more METALLIC than Na
- therefore is a better conductor
To get a MOLECULAR formula (NOT Empirical!) from Percent Mass:
- What do you need?
- How do you do it?
You need the MW of the unknown!
- Divide MW of unknown by MW of the empirical formula
- which should be a whole number
- Multiply each subscript by that #
- …to get the molecular formula
What is the definition of “Atomic Weight?”
is the mass of 1 mol of any atom (g/mol)
What are the 2 adjustements to Bohr Model?
- Electrons have dual nature–
- act as a wave AND a particle
- ex: light
- act as a wave AND a particle
- E’s DONT orbit in circular fashion
- i.e., s,p,d, & f have DISTINCT shapes
Anti Bonding vs Bonding orbitals
- Which kind is HIGHER in energy?
ANTI bonding
What does the “Pauli Exclusion Principle” state?”
- NO 2 e’s can have the exact same 4 quantum numbers
They CAN have UP TO 3 identical numbers
but they will have different spin states (4th quantum #)
Ammonium
NH4+
Ionic cpds have a hi/lo BP
High
When electron drops to a lower level, what happens?
energy is released as a photon (this is electromag. radiation)-energy released is exactly equal to diff b/t 2 energy levels
Q
rxn goes to right (favors products)
Ionic cpds are ___at room temp
solid
Carbonate
CO32-
Why does ATP being converted to ADP release energy?
because forming of new bonds in ADP releases more energy than was req’d to break bonds in ATP (energetically favorable)
Coordinate Covalent bonds: what do the donor and recipient molecules need to have?
donor: one LPrecipient: needs empty orbital
CHLORITE**
ClO2-
Isotope definition
different version of the same atom, with different # neutrons
Radioactive decay common in what kinds of questions? (2)
Conservation of momentumreverse collisions
NITRATE**
NO3-
Per coulombs law, smaller atoms have what?
Greater Force
Work function formula. What can you substitute for “E?” (2 options)
KE=E-IPyou can use E=hf OR E=hc/lamda
MANGANATE**
MnO42-
Percent yield formula
actual yield/theoretical yield x 100%
Third quantum number, aka
aka “mt” or “magnetic quantu, number
Fourth quantum number gives what?
gives the spinis either + 1/2or -1/2
Empirical vs Molecular formula
Empirical: represents lowest possible # of moles of each element that can be present in a cpd, while still maintaining the same mole-to-mole ration b/t the elements Molecular: ACTUAL # of moles of each element found in a compoundbasically, empirical is when you reduce the molecular formula as far as you can go
Beta decay
neutron changed to proton with ejection of e’
Larger atoms are better at what? What are properties of orbitals of big atoms
at stabilizing chargesdont form pi bonds, and have d orbitals where they “store” extra electrons
Q>K
rxn proceeds to left (favors reactants)
What should you remember about transition metals emitting light?
Trans metals have partially filled d orbitals-this allows e’s to absorb at many different wavelengths–color emitted is due to the few wavelengths of UNabsorbed light being reflected
- Element symbol A=
- mass number (protons + neutrons)
At a rxn equilibrium…
forward & reverse cancel outdeltaS is at maximum possible valuedeltaG is at 0
Inorganic Nomenclature: Binary cpds
name element furthest down and to the left FIRSTuse poly prefixes (di, tri, tetra) if neededSome have common names, like ammonia and water
Ionic characterWhat 2 elements have highest IC?
-all bonds between 2 different elements have IC-is a measure of polarity between bondLiCl=highest IC
Hydroxide
OH-
PT: d block
transition metals
Define le chatelier’s principle
systems already at equilibrium that experience a change will SHIFT, to reduce the effects of that change