1st Semester Things
What is the same amount as the number with the fewest in the problem
Consider the decomposition of hydrogen peroxide to water and oxygen:
2 H2O2(l) → 2 H2O(l) + O2(g) ΔH = -196 kJ
If hydrogen peroxide was in solid phase, would the enthalpy of reaction change? If so, will it decrease or increase?
What is: it will increase. H202 in liquid form takes less energy to break the bonds than when it is in solid form
Which is more likely to react with the halogens, alkali metals or alkali earth metals?
What is alkali metals
What is the graph of frequency to stopping voltage
A vertical line on the x axis until the threshold energy is met at one point it becomes linear 1:1
Why do things "want" to be in equilibrium?
It s the most stable state, and has the lowest amount of energy
The metric prefix for 1/100,000
What is micro
The molarity of a solution that was prepared by dissolving 82.0 g of CaCl2 (molar mass = 111.1 g/mol) in enough water to make 812 mL of solution?
What is 0.909 M
What is the correct name for the ionic compound, PbCO 3?
a) lead(IV) carbonate
b) lead bicarbonate
c) lead (II) carbonate
d) lead tricarbonide
What is lead (II) carbonate
How might the photoelectric effect relate to microwaves?
It is one! You can't put metal in microwaves because the radiation that microwaves provide would cause free moving electrons in the metal to leave (in the form of sparks) and blow up your kitchen
Theorize about why ice is slippery
Due to the phenomenon of "pre melt" which is when a layer on top of ice melts. This water has very little friction.
a) Separation technique used for 2 liquids.
b) Separation technique used for 2 liquids WITH similar boiling points
a) what is distillation
b) what is decanting
The steps for finding something's empirical formula
(There are multiple ways but...
What is:
1. find the empirical formula
2.find the molar mass of the empirical formula
3. divide the molar mass of the molecular formula by the molar mass of the empirical formula
4. multiply the formula by that number
Does beta radiation cause an element to move "up" or "down" the periodic table (in terms of atomic #)
What is up
Using full electron notation, what is the electron configuration for a neutral atom of magnesium?
1 s^2 2 s^2 2 p^6 3 s^2
Consider examples like boiling water (physical) versus burning wood (chemical). What's happening at the molecular level in each case?
In boiling water
- water molecules gain energy move faster, break free from the intermolecular bonds become steam
In burning wood
- chemical bonds within the wood's molecules break, new bonds formed making CO2, water vapor and ash
How do you calculate the percentage error of a result?
What is (experimental value/literature value ) x 100
Calculate the enthalpy of the following chemical reaction:
CS2(ℓ) + 3O2(g) ---> CO2(g) + 2SO2(g)
Given:
C(s) + O2(g) = CO2(g)ΔH = −393.5 kJ/molS(s) +
O2(g) = SO2(g)ΔH = −296.8 kJ/mol
C(s) + 2S(s) = CS2(ℓ)ΔH = +87.9 kJ/mol
What is -1075 kJ/mol (fully might be wrong)
Thompson's evidence for the plum pudding model
What is
- cathode rays were deflected by magnetic/electric fields indicating the existence of electrons
Which will have greater distance between particles CH2F2 or CH3^+1
CH3^+1
The reason you're out of breath in high altitude areas
What is: when you are above sea level the air pressure is lower, meaning there is less oxygen for you to breathe
The volume 2.34 grams of CO2 occupies @ STP
What is 1.19 L
An eccentric inventor attempts to levitate by first placing a large negative charge on himself and then putting a large positive charge on the ceiling of his workshop. Instead, while attempting to place a large negative charge on himself, his clothes fly off. Explain.
If you have a compound the shape of a potato, and one the shape of a green bean which will have higher intermolecular forces? (Assume same polarity)
The potato