GENERAL CHEMISTRY 2: General Chemistry I Review Flashcards
The sample represents a review of General Chemistry I for General Chemistry II.
How many significant figures are in the numbers shown below?
4.0001 meters
0.00706 meters
0.050410 meters
4.0001 meters = 5 sig figs
0.00706 meters = 3 sig figs
0.050410 meters = 5 sig figs
What are two situations where numbers will have unlimited (infinite) significant figures?
- Counting numbers are exact values and cannot be made more accurate. Example: “I have 5 pencils.”
- Known conversions are exact values and cannot be made more accurate.
Example: “1 foot = 12 inches”
Find the permimeter and area of the rectangle show below.
Hint: Report answers to the correct number of significant figures.
Remember the different rules for sig figs when multiplying/dividing versus adding/subtracting
What is the difference between a homogeneous mixture versus a heterogeneous mixture?
In homogeneous mixtures, the different particles are evenly distributed (uniform).
In heterogeneous mixtures, the different particles are not evenly distributed. In these mixtures, particles tend to congregate with one another.
Is the diagram a pure substance or a mixture?
Diagram is a pure substance, more specifically a compound.
When an element forms an anion, what is happening in terms of subatomic particles?
The element is gaining one or more electrons.
Looking at the nuclear notation of the element provided, determine the number of protons, neutrons, and electrons present.
Protons: 20
Neutrons: 22
Electrons: 18
If an ion of manganese were to have a +7 charge, how many electrons would it have?
18 electrons
Neutral manganese (Mn) has 25 protons and 25 electrons. A +7 charge indicates 7 fewer electrons than protons.
25 - 7 = 18 electrons
True or False:
The elements calcium and strontium are more chemically similar that calcium and potassium.
True: Remember that elements that are in the same group are more chemically similar than elements in the same period.
List the seven diatomic elements.
Have No Fear Of Ice Cold Beer is a useful mnemonic.
Identify each of the following as ionic or molecular compounds:
NaCl = ???
CO = ???
NH3 = ???
AgCl = ???
XeCl4 = ???
NaCl = Ionic
CO = Molecular
NH3 = Molecular
AgCl = Ionic
XeCl4 = Molecular
Provide the name for the following ionic compounds:
Provide the name for the following ionic compounds:
Provide the formula for the following ionic compounds:
Aluminum iodide = ???
Sodium nitrite = ???
Magnesium thiosulfate = ???
Cadmium phosphate = ???
Calcium oxalate = ???
Provide the name of the molecular compounds shown below:
True or False:
The number of molecules on both side of a chemical equation must be the same to have a balanced chemical equation.
False: Only the number of atoms needs to be the same to have a balanced chemical equation.
Write a balanced chemical equation from the nomenclature information:
Aqueous lead(II) nitrate reacts with aqueous potassium carbonate to produce solid lead(II) carbonate and aqueous potassium nitrate.
Using the balanced chemical equation, provide the dimensional analysis set up for determining the number of moles of chlorine gas required to produce 67.89 g of aluminum chloride. Assume excess aluminum.
Please do not solve, only provide the set up.
Grams and moles of aluminum chloride will cancel and you will be left with moles of chlorine gas
Given the balanced chemical equation and initial reaction vessel, which element is the limiting reactant and which is the excess reactant?
Element B is the limiting reactant and element A is the excess reactant.
An equimolar amount of solid aluminum and chlorine gas are placed in a reaction vessel to produce aluminum chloride. Which reactant will limit how much product can be produced?
Cl2 (g)
Per reaction, we need 3 chlorine gas molecules for every 2 aluminum atoms, meaning the chlorine gas will run out first.
4.50 moles of solid aluminum react with 4.40 moles of chlorine gas:
Based on the provided work, what is the maximum amount (in moles) of aluminum chloride that we could produce?
The maximum amount of aluminum chloride we could produce would be 2.93 moles.
We cannot make more product than what is dictated by the limiting reactant.
4.50 moles of solid aluminum react with 4.40 moles of chlorine gas:
Based on the provided work, how much of the excess reactant remains after the reaction has gone to completion?
1.57 moles of Al remaining
4.50 mols of Al initial - 2.63 mols of Al consumed = 1.57 mols Al remaining
Using the balanced chemical equation, determine how many grams of potassium chloride were obtained if we expected 100.0 grams and the precent yield of the reaction was 75.00%.
75.00 g
We are given the percent yield and the theoretical yield (we expected this amount)
Actual yield = Percent yield x Theoretical yield = 100.0 g x 0.7500 = 75.00 g
True or False:
Molecular substances are usually classified as non-electrolytes.
True