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100
Use the terms endothermic and exothermic correctly to describe chemical reactions in the laboratory.
Endothermic means it is absorbing heat, for example, heating up ice melts it (physical change).
Exothermic means it is releasing heat, for example, burning gasoline (chemical change).
100
Describe energy changes associated with chemical reactions in terms of bonds broken and formed (including intermolecular forces).
Energy is required to break bonds and is released when bonds form, if more energy is required than is released, it is endothermic, if more is released than is required, it is exothermic.
200
Given the name, write the formula of simple binary compounds.
Aluminium Phosphate
AlPO4
200
Predict products of an acid-based neutralization.
HCl + NaOH =
H2O + NaCl
200
Provide macroscopic examples, atomic and molecular explanations, and mathematical representations (graphs and equations) for the pressure-volume, pressure-temperature, and temperature-volume relationship in gases.
Heating up a balloon causes it to expand. Putting pressure on a balloon squishes it.
200
Balance simple chemical equations applying the conservation of matter:
HCl + Al2S3 = H2S + AlCl3
6HCl + Al2S3 = 3H2S + 2AlCl3
200
Calculate the amount of heat produced for a given mass of reactant from a balanced chemical equation:
6HCl + Al2S3 = 3H2S + 2AlCl3 + 600 kJ
If you used 18.0g of hydrochloric acid how many kiojoules of energy are released?
50kJ
300
Given a formula, name the compound.
Cu(NO3)3
copper (II) nitrate
300
Describe tests that can be used to distinguish an acid from a base.
Acids are sour, react with metals, have a pH below 7. Bases are bitter, slippery, have a pH above 7.
300
Measure, plot, and interpret the graph of the temperature versus time of an ice-water mixture, under slow heating, through melting and boiling.
The flat line on the graph is the point where the phase change occurs.
300
A balanced chemical equation will allow one to predict the amount of product formed:
6HCl + Al2S3 = 3H2S + 2AlCl3
If you used 18.0g of hydrochloric acid how many grams of aluminum chloride could you produce?
22.0g
300
Explain why it is necessary for a molecule to absorb energy in order to break a chemical bond.
The bonds have to be broken first for the reaction to start.
400
Given the name, write the formula of ionic and molecular compounds: Iron (II) sulfate
FeSO4
400
Classify various solutions as acidic or basic, given their pH:
pH 0-7 & pH 7-14
pH 0-7 acidic, pH 7-14 basic
400
Calculate the number of moles of any compound or element given the mass of the substance:
MgSO4
The total weight is 120 g/mol. If you have 30 grams of it, that would be 0.25 moles
400
Predict single replacement reactions.
CuSO4 + Mg = ...
CuSO4 + Mg = MgSO4 + Cu
400
Explain why freezing is an exothermic change of state.
Because energy is released as the particles slow down to form physical bonds.
500
Predict the formula for binary compounds of main group elements: The formula for the compound formed between calcium and nitrogen is...
Ca3N2
500
Calculate the pH from the hydronium concentration.
Using the -log[H+] = pH, if the H+ is 0.00040 the pH is...
pH is 3.398
500
Calculate the percent by weight of each element in a compound based on the compound formula:
MgSO4
The total weight is 120 g/mol.
Magnesium is 24 g/mol, so (24/120)*100% = 20%
Sulfur is (32/120)*100% = 26.7%
Oxygen is (64/120)*100% = 53.3%.
500
If four molecules of ammonia undergo decomposition, how many molecules of nitrogen and hydrogen will form?
2 molecules of nitrogen and 6 molecules of hydrogen?
500
Compare the energy required to raise the temperature of one gram of aluminum and one gram of water the same number of degrees.
Water has a very high specific heat, so it requires more energy to raise its temperature per gram than aluminum: using the formula q=CmT