Intermolecular Forces
What are the 3 intermolecular forces?
Rank from weakest to strongest
London Dispersion
Dipole-Dipole
Hydrogen Bonding
How many calories are in 1 kilocalorie?
1000 calories
Endothermic
What is to the left of the arrow and to the right of the arrow in a chemical reaction?
Left: Reactants
Right: Products
What is Avogadro's Number?
6.022 x 10^23
You have to compare which of 2 substances have a higher intermolecular force but the catch is that they have the same forces, what do you do?
Look at which substance is larger.
The bigger the substance in size or weight, the strong the forces will be
What is the conversion factor for calories to joules?
1 calorie = 4.184 joules
Solid -> Liquid = ?
Melting
Why are coefficients used in chemical equations
To balance the equation
How much does 1 mole of anything weigh?
(include possible units)
1 mole = 6.022 x 10^23 atoms/molecules/particles/ions
What requirements are needed to satisfy hydrogen bonding?
Hydrogen bonded to a N, O, or F
What is the specific heat equation?
(Words or units work)
SH = heat / mass * delta T
or
SH = calories / g * degrees Celsius
Liquid -> Gas = ?
Vaporization
What is the theory that explains why atoms cannot be created or destroyed in a chemical reaction
Law of conservation of mass
How much does 1 mole of sodium nitrite weigh?
69 g NaNO2 / 1 mole NaNO2
or
69 g/mole NaNO2
What forces are happening on this molecule?
C17H26
London Dispersion
Estimate the number of Calories (food calories!) in a serving of oatmeal that has 4 g of protein, 19 g of carbs, and 2 g fat. Round off your answer to the closest whole number.
Help: 4 Calories of Protein or Carbs / 1 g
9 Calories of Fat/ 1 g
110 Calories
True/False: chemical bonds DO change with phase changes (melting and freezing)
FALSE: chemical bonds DO NOT change, they just get more DISORGANIZED
Balance this equation: H2 + O2 -> H2O
2H2 + O2 -> 2H2O
How many grams are contained in 5.00 moles of Na2SO4?
710 g Na2SO4
Rank the following molecules from weakest to strongest IMF:
1. H2O
2. CH4
3. NaCl
4. NaBr
5. C3H8
CH4, C3H8, NaCl, NaBr, H2O
If it takes 37.0 cal of heat to raise the temperature of 12.0 g of a substance by 8.5 degrees Celsius, what is its specific heat?
0.36 cal/ g * degrees Celsius
What are the units for heat of (fusion/vaporization)?
It will bea conversion factor for future reference!
Ca(OH)2 + 2 HNO3 -> 2 H2O + Ca(NO3)2
How many moles are contained in 25.0 g of fructose (C6H12O6 - molar mass = 180.15 g/mol)?
0.139 mole fructose
or
1.39 x 10^-1 mole fructose