GENERAL CHEMISTRY 2: General Chemistry I Review Flashcards

The sample represents a review of General Chemistry I for General Chemistry II.

1
Q

How many significant figures are in the numbers shown below?

4.0001 meters

0.00706 meters

0.050410 meters

A

4.0001 meters = 5 sig figs

0.00706 meters = 3 sig figs

0.050410 meters = 5 sig figs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are two situations where numbers will have unlimited (infinite) significant figures?

A
  1. Counting numbers are exact values and cannot be made more accurate. Example: “I have 5 pencils.”
  2. Known conversions are exact values and cannot be made more accurate.
    Example: “1 foot = 12 inches”
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Find the permimeter and area of the rectangle show below.

Hint: Report answers to the correct number of significant figures.

A

Remember the different rules for sig figs when multiplying/dividing versus adding/subtracting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the difference between a homogeneous mixture versus a heterogeneous mixture?

A

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.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Is the diagram a pure substance or a mixture?

A

Diagram is a pure substance, more specifically a compound.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

When an element forms an anion, what is happening in terms of subatomic particles?

A

The element is gaining one or more electrons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Looking at the nuclear notation of the element provided, determine the number of protons, neutrons, and electrons present.

A

Protons: 20
Neutrons: 22
Electrons: 18

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

If an ion of manganese were to have a +7 charge, how many electrons would it have?

A

18 electrons

Neutral manganese (Mn) has 25 protons and 25 electrons. A +7 charge indicates 7 fewer electrons than protons.

25 - 7 = 18 electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

True or False:

The elements calcium and strontium are more chemically similar that calcium and potassium.

A

True: Remember that elements that are in the same group are more chemically similar than elements in the same period.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

List the seven diatomic elements.

A

Have No Fear Of Ice Cold Beer is a useful mnemonic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Identify each of the following as ionic or molecular compounds:

NaCl = ???

CO = ???

NH3 = ???

AgCl = ???

XeCl4 = ???

A

NaCl = Ionic

CO = Molecular

NH3 = Molecular

AgCl = Ionic

XeCl4 = Molecular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Provide the name for the following ionic compounds:

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Provide the name for the following ionic compounds:

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Provide the formula for the following ionic compounds:

Aluminum iodide = ???

Sodium nitrite = ???

Magnesium thiosulfate = ???

Cadmium phosphate = ???

Calcium oxalate = ???

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Provide the name of the molecular compounds shown below:

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

True or False:

The number of molecules on both side of a chemical equation must be the same to have a balanced chemical equation.

A

False: Only the number of atoms needs to be the same to have a balanced chemical equation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

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.

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

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.

A

Grams and moles of aluminum chloride will cancel and you will be left with moles of chlorine gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Given the balanced chemical equation and initial reaction vessel, which element is the limiting reactant and which is the excess reactant?

A

Element B is the limiting reactant and element A is the excess reactant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

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?

A

Cl2 (g)

Per reaction, we need 3 chlorine gas molecules for every 2 aluminum atoms, meaning the chlorine gas will run out first.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

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?

A

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.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

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?

A

1.57 moles of Al remaining

4.50 mols of Al initial - 2.63 mols of Al consumed = 1.57 mols Al remaining

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

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%.

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

True or False:

Molecular substances are usually classified as non-electrolytes.

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

In the picture, identify the solution that represents a strong electrolyte, the weak electrolyte, and the non-electrolyte.

A

I = Strong electrolyte.
II = Weak electrolyte.
III = Non-electrolyte.

26
Q

Classify each compound in the picture as a strong electrolyte, a weak electrolyte, or a non-electrolyte.

A
27
Q

Provide the dimensional analysis set up for determining the number of grams of sodium chloride present in 565 mL of a 0.576 M solution of sodium chloride. Note: MW of sodium chloride is 58.44 g/mol

Please do not solve, only provide the set up.

A
28
Q

In a 1.0 M aqueous solution of potassium sulfate, how would you relate concentration of potassium ions in solution to the concentraion of sulfate ions in solution?

A
29
Q

Determine whether each of the following ionic compounds is soluble or insoluble in water.

A
30
Q

Sodium hydroxide reacts in solution with iron(III) chloride. Predict the products of this reaction and write a balanced chemical equation (including states of matter).

A

Products are insoluble iron(III) hydroxide and soluble sodium chloride.

31
Q

Write out a balanced chemical equation, the total ionic equation, and the net ionic equation when nickel(II) bromide reacts with silver nitrate in solution.

A
32
Q

What are the spectator ions when lead(II) nitrate reacts with potassium sulfate?

A

The spectator ions are the potassium ion and the nitrate ion.

33
Q

A student is forming carbon disulfide in a reaction flask. Once the reaction has completed, the flask is colder than it was before the reaction started. Is this an endothermic or exothermic reaction?

A

Endothermic reaction

34
Q

Classify each of the following as a path function or a state function:

Enthalpy = ???
Work = ???
Heat = ???
Internal energy = ???

A

Enthalpy = State function
Work = Path function
Heat = Path function
Internal energy = State function

35
Q

If ΔH = -45 J, what does this mean for the system and the surroundings? Does this represent an endothermic or an exothermic process?

A

The system is losing 45 J while the surroundings are gaining 45 J.

This represents an exothermic process.

36
Q

Two metal spheres that are the same mass, but have different specific heat capacities are shown in the picture. If both spheres are heated, which sphere would feel warmer after 5 minutes?

A

Sphere 1

37
Q

Two metal spheres that are the same mass, but have different specific heat capacities are shown in the picture. If each sphere were heated to 200 C° and dropped in a bucket of water, which sphere would cause the water’s temperature to increase the most?

A

Sphere 2

Both sphere are heated to 200 C°, but the sphere with the higher specific heat capacity will cause the water’s temperature to increase the most.

38
Q

A piece of silver metal with a mass of 125 g is placed into a refrigerator. If the
initial temperature of the silver metal was 75.0 °C, and it is cooled to 10.0 °C, how much heat (kJ) did the refrigerator absorb? Note: The specific heat of silver is 0.235 J/g∙°C.

A

1910 J

39
Q

What is atomic radius? What is the trend for atomic radius using the periodic table?

A

Atomic radius is defined as the half distance between nuclei in a molecule consisting of identical atoms.

Moving down a given group on the periodic table, the atomic radius will increase. As you go down a group on the periodic table, the principal quantum number of the valence orbitals increases. There are more electron orbitals further from the nucleus, increasing the atomic radius.

Moving across a period from left to right on the periodic table, the atomic radius will decrease. This is caused by the increase in the effective nuclear charge as the strength of positive charge increases in the nucleus.

40
Q

How is atomic radius impacted when an ion forms?

A

The formation of a cation or anion has an impact on atomic radius. When an ion forms, we can look at the ionic radius.

Cations: When an element loses an electron and becomes a positively charged species, the ion is smaller than the neutral atom.

Anions: When an element gains an electron and becomes a negatively charged species, the ion is larger than the neutral atom.

41
Q

Describe the general trend for ionization energy as seen on the periodic table.

A

Moving across a period from left to right on the periodic table, the ionization energy will increase. It is more difficult and energy-intensive to remove an electron from a species farther right in a period due to the increase in Zeff.

Moving down a given group on the periodic table, the ionization energy will decrease. It is easier to remove electrons from larger species due to the increasing distance between valence electrons and the nucleus.

42
Q

What is the general trend for electron affinity?

A

Moving across a period from left to right on the periodic table, the electron affinity of the atom will increase. This is caused by a decrease in atomic radius and an increase in effective nuclear charge.

Moving down in a group of atoms on the periodic table, the electron affinity will decrease. This is caused by added electrons being farther from the nucleus as the atom increases in size and that added electrons experience more repulsive forces from other electrons.

43
Q

True or False:

The compound potassium sulfate is an example of a compound that contains only ionic bonding.

A

False: The polyatomic ion sulfate is held together via covalent bonding while the bond between sulfate and the potassium ion is an example of an ionic bond.

Potassium sulfate contains both covalent and ionic bonding.

44
Q

Describe the general trend for electronegativity on the periodic table.

A

Electronegativity increases from left to right across the period and increases from the bottom to the top of a group.

45
Q

What is the difference between a polar covalent bond and a non-polar covalent bond?

A

Non-polar covalent bonds arise when there is not a great difference in electronegativity between the two atoms forming the bond. Electrons will be shared equally.

Polar covalent bonds arise when two atoms with larger differences in electronegativities are bound together. When two atoms having larger differences in electronegativities are bound together, the atoms will share electrons within the bond unevenly.

46
Q

Looking at the polar covalent bond in H-F, where would the partial positive charge go and where would the partial negative charge go?

A

Remember that in a polar covalent bond, the partial positive charge will go on the more electropositive atom and the partial negative charge will go on the more electronegative atom.

47
Q

What is the formula for determining formal charge?

A
48
Q

Draw the Lewis structure for the following molecules:
1. Sulfur tetrachloride
2. Xenon difluoride
3. Ammonia

A
49
Q

Draw the Lewis structure for propanoic acid (CH3CH2COOH) and answer the following questions:
How many single bonds are present in the Lewis structure?
How many double bonds are present in the Lewis structure?
How many triple bonds are present in the Lewis structure?
How many lone pairs of electrons are present in the Lewis stucture?

A

Single bonds = 9
Double bonds = 1
Triple bonds = 0
Lone Pairs = 4

50
Q

Two resonance forms for benzene are shown. How are these two forms different from one another?

A

The two resonance structures for benzene differ from one another by the placement of electrons only.

51
Q

Draw the Lewis structure for the carbonate ion. How many equivalent resonance strucutres are possible?

A

There are 3 equivalent resonance forms for carbonate.

52
Q

What is the difference between electronic geometry and molecular geometry?

A

Electronic geometry looks at ALL pairs of electrons surrounding the central atom of a compound. This includes electrons involved in bonding AND lone pairs of electrons.

Molecular Geometry ONLY looks at pairs of electrons involved in bonding. It does not consider lone pairs of electrons.

53
Q

Determine the electronic geometry given the following regions of electron density:

2 regions of electron density = ???
3 regions of electron density = ???
4 regions of electron density = ???
5 regions of electron density = ???
6 regions of electron density = ???

A

2 regions of electron density = Linear
3 regions of electron density = Trigonal planar
4 regions of electron density = Tetrahedral
5 regions of electron density = Trigonal bipyramidal
6 regions of electron density = Octahedral

54
Q

Draw the Lewis structure for Iodine pentafluoride and answer the following questions:
What is the electronic geometry?
What is the molecular geometry?
How many bonding pairs of electrons are present?
How many lone pairs are present on the central atom?

A

Electronic geometry = Octahedral
Molecular geometry = Square pyramindal
Bonding pairs of electrons = 5
Lone pairs on central atom = 1

55
Q

True or False:

If a molecule contains polar bonds, then it must be a polar molecule.

A

False: Just because a molecule has polar bonds does not mean that it is a polar molecule. It will depend on if the dipoles cancel out or not.

56
Q

What molecular geometries are associated with always being polar?

A

Bent
Trigonal pyramidal
Seesaw
T-Shaped
Square pyramidal

57
Q

Draw the Lewis structure for xenon dichloride and answer the following questions:
What is the electronic geometry?
What is the molecular geometry?
Is the molecule polar or non-polar?

A

Electronic geometry = Trigonal bipyramidal
Molecular geometry = Linear
Polarity = Non-polar

58
Q

The molecular structure for caffeine is provided in the picture. Determine how many sigma and pi bonds are present in the structure.

A

Sigma bonds: 25
Pi bonds: 4

59
Q

The structure of propofol, which is widely used as an anesthetic, is shown. How many sp3 hybridized atoms are in the molecule?

A

7 sp3 hybridized atoms.

There are 6 sp3 hybridized carbons and 1 sp3 hybridized oxygen. The sp3 hybridized atoms are circled in the picture.

60
Q

The central atom of a molecule has trigonal bipyramidal electronic geometry. Determine the hybridization of the central atom.

A
61
Q

Draw the Lewis structure for water and determine the electronic geometry, molecular geometry, polarity, and hybridization of the central atom.

A

Electronic geometry = Tetrahedral
Molecular geometry = bent
Polarity = Polar
Hybridization = sp3