Final Exam Flashcards
Decomposition Reaction
One reactant breaks down into two or more elements.
AB –> A + B
Is the solution unsaturated, saturated, or supersaturated, if I have 30 g of Potassium Nitrate in 100 g of Water at 30 C?
Unsaturated
Quantum of Energy
Absorbed when an electron moves from its ground state to its excited state.
Period
Horizontal row on the periodic table.
What is the percent composition of oxygen in CuSO₄?
mass of CuSO₄= 63.546 + 32.065 + 4(15.999) = 159.7 grams
Mass of oxygen = 4(15.999) = 64 grams
(64/159.7) x (100%) = 40.1. %O
A compound contains 21.6 g of silver and 3.21 g of sulfur, what is the percent composition?
21.6/(21.6+3.21) = 87.1% Ag
3.21/(21.6+3.21) = 12.9%S
Fusion
Solubility Curve
Used to determine the mass of solute in 100g (100ml) of water at a given temperature.
HCl + Zn →
2HCl + Zn →ZnCl₂ + H₂ Single Replacement
What are both of the symbols for each of the following types of nuclear decay:
Alpha, Beta, Gamma
Ductile
Capable of being drawn out into a wire or thread.
Weak Acid
Weak acids are not fully ionized or dissociated.
To convert a number less than 1 to scientific notation?
the original decimal point is moved n places to the right, and the resulting number is multiplied by 10^-n.
Turning Standard Notation into Scientific Notation
If the number is greater than 1, the exponent will be positive.
If the number is less than 1, the exponent will be negative.
Scientific Notation Example
Scientific notation (exponential notation) represents very large or very small numbers as powers of ten.
Write a chemical equation from the following word equation:
Magnesium reacts with aluminum chloride to form magnesium chloride and aluminum.
3Mg + 2AlCl₃–> 3MgCl₂ + 2Al
Charge of Group 16 or 6A (O,S, Se, Te):
Charge: 2-
Convert 71,200 inches to miles.
1 ft = 12 inches
1 mile = 5280 feet
Atomic Mass Number
Also known as the Mass Number or Atomic Mass.
What do significant figures show?
Precision
Metals
To the left side of the periodic table (left of the zig zag line).
Usually, solids at room temperature.
Good conductors of heat and electricity.
High melting and boiling points.
Malleable.
Ductile.
In the equation:
4Al + 3O₂→ 2Al₂O₃,
how many moles of Al₂O₃will be produced if there are 3.75 moles of O₂?
- 75 moles O₂ x (2 moles Al₂O₃/ 3 moles O₂) =
- 50 moles Al₂O₃
Anion
Negatively charged Ions. Anions are negatively charged because they have gained an electron(s) (electrons are negative). In general, anions are nonmetals.
Charge of Group 1 or 1A (H, Li, Na, K, Rb, Cs):
Charge = 1+
Diatomic Molecules
If these elements appear by themselves in an equation, the must be in pairs with the subscript 2.
(H₂, N₂, O₂, F₂, Cl₂, Br₂, I₂)
Predict the products of and write a balanced equation from the following statement:
CuCl₂ + H₂S →
CuCl₂ + H₂S →CuS + 2HCl
Double Replacement
Violations of the Octet Rule
Be - 4
B - 6
P - 8 or 10
S - 8, 10, or 12
Xe - 8, 10, or 12
Group or Family
Vertical Column on the periodic table. Elements in the same family have similar properties.
Percent Yeild
A measure of the efficiency of a reaction carried out in the laboratory.
Gases deviate most from ideal behavior under conditions of very ______ temperature and very _______ pressure
low; high
Law of Conservation of Mass
Mass is neither created or destroyed during a chemical reaction - it is conserved.
Mass Reactants = Mass Products
In the equation:
NH₄NO₃ → N₂O + 2H₂O
How many grams of H₂O are produced if you are given 50 g of NH₄NO₃?
50 g NH₄NO₃ x (1 mole NH₄NO₃ /80.04 gNH₄NO₃) x
(2 moles H₂O / 1 mole NH₄NO₃) x (18.02 g H₂O/ 1 mol H₂O) =
22.5 g H₂O
Proton
Positively charged subatomic particle. Contained inside the nucleus. Neutrons and Protons weigh roughly the same (1 atomic mass unit).
Charge of Group15 or 5A (N, P, As):
Charge = 3-
Inversely Proportional
As the value of one variable increases, the value of the other decreases and vice-versa (e.g., pressure and volume)
Reactants
Substances being mixed in a chemical reaction. The left side of the equation.
Conductor
A material which permits the flow of energy. A material which allows the flow of charged particles is an electrical conductor. A material which allows the transfer of thermal energy is a thermal conductor or heat conductor.
Charge of Group17 or 7A (F, Cl, Br, I)
Charge: 1-
Predict the products and write a balanced equation from the following word statement:
Methane (CH₄) plus Oxygen Gas forms:
Writing Formulas for Ionic Bonds
Absolute Value Criss Cross Oxidation #’s
Mg + I₂ →
Mg + I₂ →MgI₂ Synthesis
CaCl₂ + K₂CO₃ →
CaCl₂ + K₂CO₃ →CaCO₃ + 2KCl Double Replacement
Coefficients
The large numbers in front of chemical formulas. Represent the number of molecules of the substance in the reaction.
2Cl
Directly Proportional
As the value of one variable increases, the value of the other increases and vice-versa (e.g., temperature and volume, temperature and pressure)
How much solute will not dissolve if I have 80g of Potassium Nitrate in 100g of Water at 30C?
35g Potassium Nitrate
When multiplying and dividing with Significant Figures, ___________________.
round to least number of sig figs
Rules for Significant Figures?
1) ALL non-zero numbers (1,2,3,4,5,6,7,8,9) are ALWAYS significant.
2) LEADING zeroes are NEVER significant
3) Zeroes CAPTURED between non-zero numbers are ALWAYS significant.
4) TRAILING zeroes without a decimal are NEVER significant
5) TRAILING zeroes with a decimal are ALWAYS significant.
6) When using SCIENTIFIC NOTATION all digits in front of “x 10‾³” or “E-3” are ALWAYS significant
Standard Temperature & Pressure (STP) - a shorthand method that can be used when writing word problems.
Balance the following chemical equation:
__C + __O₂ → __CO₂
1C + 1O₂ → 1CO₂
The three types of radiation and their penetration abilities:
How to PREDICT PRODUCTS of the 4 Main Types of Chemical Reactions.
If the total pressure of a two gas system is 100 torr and the partial pressure of one gas is 70 torr, what is the pressure of the other gas?
Pother = 30 torr
Negative Exponents in Scientific Notation
Negative Exponents in Scientific Notation mean you should move the decimal to the left to change the number to standard notation.
STANDARD SOLUTION
Solution of known concentration
Vapor Pressure
The pressure of the vapor resulting from evaporation of a liquid (or solid) above a sample of the liquid (or solid) in a closed container.
Ideal Gas
A gas that behaves exactly as the Kinetic Molecular Theory describes
Hydronium Ion
[H+]
Oxidation Numbers
In Order +1 +2 Break until Boron +3 +4 -4 -3 -2 -1 0 at Helium
Scientific Notation in TI-84 and class calculators
(Number) 2nd EE (Exponent)
Hint: negative button is not the minus button
Electrons
Negatively charged subatomic particles. Electrons can be found in the space around the nucleus. This area is often called the electron cloud. Electrons have NO mass.
Anions
Anions are named by adding the suffix -ide to the stem of the name of the nonmetal from which they are derived. N³⁻ = Nitride O²⁻ = Oxide F⁻ = Flouride
A balloon with a volume of 2.0 L is filled with a gas at 3 atmospheres. If the pressure is reduced to 0.5 atmospheres without a change in temperature, what would be the volume of the balloon?
Since the temperature does not change, Boyle’s law can be used. Boyle’s gas law can be expressed as:
PiVi = PfVf (i=initial and f=final)
To find the final volume, solve the equation for Vf:
Vf = PiVi/Pf
Vi = 2.0 L
Pi = 3 atm
Pf = 0.5 atm
Vf = (2.0 L)(3 atm)/(0.5 atm)
Vf = 6 L/0.5
Vf = 12 L
Answer:
The volume of the balloon will expand to 12 L.
Write a chemical equation from the following word equation:
Lithium chloride reacts with magnesium nitrate to form lithium nitrate and magnesium chloride.
2LiCl + Mg(NO₃)₂ –> 2Li(NO₃) + MgCl₂
Ionic Compound Formulas
- Metal written first Nonmetal written second 2. Use criss-cross method and subscripts to insure sum of charges = 0
Convert 89.2 inches to centimeters.
2.54 cm = 1 inch
Neutrons
Neutrally charged subatomic particle. (No charge) Contained inside the nucleus. Neutrons and Protons weigh roughly the same (1 atomic mass unit)
Roman Numerals
Above groups/families Roman Numerals represent the number of valence electrons.
When writing the name of an ionic compound which includes a transition metal a Roman Numeral is used to denote the quantity of positive charge associated with that transition metal.
Properties of Bases
Bitter and slippery
Principle Energy Level
The possible locations around an atom where electrons having specific energy values (quantum number) may be found. Divided into sublevels s, p, d, and f.
In the equation:
2Na + Cl₂→ 2NaCl
How many grams of NaCl are produced from 3.75 moles of Cl₂?
- 75 moles Cl₂ x ( 2moles NaCl/1 mole Cl₂ ) x ( 58.5g NaCl / 1 mol NaCl =
- 75 g NaCl
Solvent
The component doing the dissolving.
The component in the largest amount.
Water is the universal solvent.
If pressure is constant, the volume of a sample of gas _____________ as temperature increases.
increases
At constant pressure, the volume of a sample of gas is ___________ proportional to temperature as measured on the ____________ temperature scale
directly; Kelvin
Polyatomic Ionic Formulas
- Metal written first, Polyatomic Ion is written second 2. Use criss-cross method and subscripts to insure sum of charges = 0 3. When using a subscript for polyatomic ions: place a parentheses around the polyatomic formula, put the subscript outside of the parentheses
If the [H+] =1E-5 in a Coca-Cola what is the concentration of [OH-]? Is the solution acidic, basic, or neutral?
[H+] [OH-] = 1E-14
[OH-] = (1E-14) / ([H+])
[OH-] = (1E-14) / (1E-5)
[OH-] = 1E-9
The solution is acidic because 1E-5 is less than 1E-7.
How many moles are in 3.67 x 10²⁴ molecules of SO₂?
- 67 x 10²⁴ molecules SO₂ x (1 mole SO₂/6.02x10²³ molecules SO₂)=
- 10 moles SO₂
Diatomic Molecule
If these elements appear by themselves in an equation, the must be in pairs with the subscript 2.
What is the molarity of a solution in which 58 g of NaCl are dissolved in 1.0 L of solution?
1.0 M
Malleable
Able to be hammered or pressed permenately out of it’s original shape without breaking or cracking.
CuCl₂ + H₂S →
CuCl₂ + H₂S →CuS + 2HCl Double Replacement
Write a chemical equation from the following word equation:
Water decomposes into hydrogen gas and oxygen gas:
2H₂O → 2H₂ + O₂
Properties of Ionic Compounds
Crystalline Structure High Melting Point Rigid Strong Bond Conduct Electricity (when dissolved or melted) Good Insulators
Given the following reaction: S₈ + 4Cl₂ → 4S₂Cl₂. If there is 200g of sulfur and 100g of chlorine, what mass of disulfur dichloride will be produced?
- Perform a mass-to-mass calculation between sulfur and disulfur dichloride.
200g S₈ x (1mol S₈ / 256.5g S₈) x (4mol S₂Cl₂ / 1 mol S₈) x (135g S₂Cl₂ / 1 mol S₂Cl₂) = 421g S₂Cl₂.
- Perform a mass-to-mass calculation between chlorine and disulfur dichloride.
100g Cl₂ x (1mol Cl₂ / 70.91g Cl₂) x (4mol S₂Cl₂ / 4 mol Cl₂) x (135g S₂Cl₂ / 1 mol S₂Cl₂) = 190.4g S₂Cl₂.
The limiting reactant is chlorine (Cl₂ ) because… it produced only 190.4g S₂Cl₂.
The excess reactant is sulfur (S₈) because… it would have produced 421g S₂Cl₂.
Octet Rule
All atoms other than hydrogen and helium bond to fill their valence shell with eight electrons.
Are zeros after a decimal and before a significant digit “significant” or “not significant”?
Not Significant
Atmospheric Pressure
Pressure resulting from the collisions of atoms and molecules with objects.
Symbols used in writing chemical equations
Predict the products of and write a balanced equation from the following statement:
Mg + I₂ →
Mg + I₂ →MgI₂
Synthesis
NEUTRALIZATION REACTION
When an acid and base react in solution to form salt and water.
Ionic Bond
Metals GIVE electrons, Nonmetals TAKE electrons
Balance the following chemical equation:
__C₂H₆ + __O₂ → __CO₂ + __H₂O
2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O
Saturated
Contains as much solute as it can at that temperature.
If you add more solute it will not dissolve.
Strong Acid
Completely dissociates.
pH, pOH, [H+], [OH-] Calculation Road Map
If 2.5g of sulfur hexafluoride is introduced to an evacuated 500.0mL container at 83*C, what is the pressure, in atmospheres, inside the container?
PV = nRT
2.5g SF6 (1mole SF6/ 146.08 g SF6) = 0.017 moles SF6
P = (nRT)/V
P =[ (0.017 moles)x(0.08205746 L atm/K mol)x(83+273K)/(.5 L)
P =0.99atm
Combustion
Any compound formed from only Carbon an Hydrogen (fuel) added to Oxygen to produce Carbon Dioxide and Water.
Boyle’s Law
The pressure and volume of a gas are inversely proportional at a constant temperature.
P1V1 = P2V2
Ideal Gas Law
Metalloid
Have properties of both metals and nonmetals.
Semiconductors.
Transition Metals
Are zeros before significant digits “significant” or “not significant”?
Not Significant
Nucleus
The center of an atom. Contains the protons and neutrons. Since neutrons have no charge and protons are positively charged, the nucleus has an overall positive charge.
Na + MgCl₂ →
2Na + MgCl₂ →2NaCl + Mg Single Replacement
Titration Curve
Atomic Size
Size of an atom.
Depends on the number of energy levels and the overall charge of the nucleus (the nucleus’s charge depends on the number of protons).
As you go down a group you are adding energy levels (rings around the nucleus) so the atomic size increases.
As you go across a period the atomic size decreases because the energy levels (which contain negative electrons) are increasingly attracted to the positive protons in the nucleus of the atom.
Ions
Atoms or groups of atoms with a charge. To have a charge an atom must have gained or lost electrons. If an atom gains electrons it becomes negatively charged. If an atom loses electrons it will become positively charged.
Calculate the pH of a solution with a Hydronium ion concentration of 1.3E-9 M
pH= -log(1.3E-9) =8.89
What mass of copper (II) sulfide is equal to 4.79 x 10²² atoms?
- 79 x 10²² atoms CuS x (1 mole CuS/6.02x10²³ atoms CuS) x (95.61 g CuS/1 mole CuS) =
- 61 g CuS
Covalent or Molecular Compounds (Molecules)
The first word gives name of the element that appears first preceded by a prefix that shows number of atoms in that element. Do NOT use the prefix mono before the name of the first element. The second word consists of a prefix designating the number of atoms of that element, the stem name of the second element, and the suffix -ide.
How many atoms are in 2.7 moles of iron?
2.7 moles Fe x (6.02x10²³ atoms Fe/1 mole Fe) =
1.6 x 10²⁴atoms Fe
K + Cl₂ →
2K + Cl₂ →2KCl Synthesis
Is the solution unsaturated, saturated, or supersaturated, if I have 60g of Potassium Nitrate in 100g of Water at 30 C?
Supersaturated
Significant Figures
All the digits in a measurement that are known with certainty plus a last digit that must be estimated.
Sublevel
Principal energy levels are broken down into sublevels designated s, p, d, or f upon which electrons travel.
Combined Gas Law
P1V1T2 = P2V2T1
Dalton’s Law of Partial Pressures
Bases
Electron donator.
Yeilds OH- in solution.
H+ Ion acceptor.
Write the formula for Mg²⁺ and PO₄³⁻
Using the criss-cross method and subscripts to insure sum of charges is zero: Mg₃(PO₄)₂
Dimensional Analysis
A method of mathmatical analysis which involves converting between units.
Orbital Diagram
Shorthand method of writing the location of electrons by orbital.
Rules for Multiplying and Dividing with Significant Figures
The result has the same number of significant figures as the factor with the fewest significant figures.
Predict the products of and write a balanced equation from the following statement:
HCl + Zn →
2HCl + Zn →ZnCl₂ + H₂
Single Replacement
A cylinder contain a gas of volume 30 L, at a pressure of 110 kPa and a temperature of 420 K. Find the temperature of the gas which has a volume 40 L at a pressure of 120 kPa.
Vi = 30 L, Pi = 110 kPa, Ti = 420 K, Vf = 40 L, Pf = 120 kPa
Final Temperature(Tf) = PfVfTi / PiVi
Tf= (120kPa x 40L x 420K) / (110kPa x 30L)
Tf = 610.91 K
Duet Rule
Hydrogen bonds to fill it’s valence shell with two electrons. Helium already has two electrons and thus does not need to form bonds to increase stability.
Double Displacement
There are two compounds on each side of the equation. During a DD Reaction the positively charged cations in each compound switch places. Also known as Precipitate Reaction.
AB + CD –> AD + CB
A 600 mL sample of nitrogen is heated from 27 °C to 77 °C at constant pressure. What is the final volume?
The first step to solving gas law problems should be converting all temperatures to absolute temperatures. This is the most common place mistakes are made in this type of homework problem.
K = 273 + °C
Ti = initial temperature = 27 °C
K = 273 + 27
Ki = 300 K
Tf = final temperature = 77 °C
K = 273 + 77
Kf = 350 K
The next step is to use Charles’ law to find the final volume. Charles’ law is expressed as:
ViTf = VfTi
where
Vi and Ti is the initial volume and temperature
Vf and Tf is the final volume and temperature
Solve the equation for Vf:
Vf = ViTf/Ti
Enter the known values and solve for Vf.
Vf = (600 mL)(350 K)/(300 K)
Vf = 700 mL
Answer:
The final volume after heating will be 700 mL.
Cations
Positively Charged Ions. In general, cations are metals.
Atomic Number
Identifies an element. The number of protons. For a neutral atom, the number of electrons will equal the number of protons. For an ion (charged atom) the number of electrons will not be the same as the atomic number.
Products
Substance(s) being made. Right side of the equation.
Hydroxide Ion
[OH-]
Charge of Group 2 or 2A (Be, Mg, Ca, Sr, Ba):
Charge = 2+
Oxidation Number
Ion Charge - number of electrons transferred to or away from an atom when it becomes an ion.
Are digits 1-9 “significant” or “not significant”?
Significant
Dilute
Relatively small amount of solute.
Determine the conjugate acid/base pairs.
NH3 + H2O —> NH4+ + OH-
How to deterermine if a solution is unsaturated, saturated, or supersaturated.
Add more solute and observe the results.
How much solute would crystallize out of solution once a solution of 85g of Potassium Nitrate in 100g of Water at 50C is cooled to 20C?
55g Potassium Nitrate
Kinetic Energy
The energy an object has due to its motion.
Molarity
M
Properties of Acids
Sour
In the equation:
C₃H₈ + 5O₂→ 3CO₂+ 4H₂O
How many moles of CO₂are produced when 7 moles of C₃H₈ are burned?
7 moles C₃H₈ x (3 moles CO₂ / 1 mole C₃H₈) =
21 moles CO₂
Scientific Notation
A way of expressing really large or really small numbers.
Solute
The component being dissolved.
The component in the smallest amount.
Isotopes
Atoms of the same element which have a different Mass Number due to a differing number of neutrons.
The symbol for an Isotope is the element symbol followed by the Mass Number, for example:
Na-23 and Na-24
Non Polar Covalent
A type of covalent bond between two atoms in which electrons are shared equally.
Calculate the % Yield of solid silver chromate produced in the following reaction:
K₂CrO₄ + 2AgNO₃ → Ag₂CrO₄ + 2KNO₃
In the reaction there was .500g of the limiting reactant AgNO₃. In the actual experiment, .455g of Ag₂CrO₄ was produced.
Calculating the Theoretical Yield of Ag₂CrO₄ that was produced:
0.500g AgNO₃ x (1 mole AgNO₃ / 169.9g AgNO₃) x
(1mole Ag₂CrO₄ / 2 mole AgNO₃) x (331.7 g Ag₂CrO₄ / 1 mol Ag₂CrO₄) =0 .488g Ag₂CrO₄.
Find the ratio of the actual yield (.455g) to the theoretical yield (.488g) …
% Yield = (.455g Ag₂CrO₄ ÷ .488g Ag₂CrO₄ ) x 100 =
93.2 %
Intermolecular Forces
Attractive forces BETWEEN molecules
Concentrated
A relatively large amount of solute.
Radioactivity
When the nucleus of an atom becomes unstable and decays. This tends to happen to large atoms (larger than atomic number 83) becuase the number of protons to neutrons in the nucleus is unbalanced.
Predict the products of and write a balanced equation from the following statement:
C₄H₆ + O₂ →
2C₄H₆ + 7O₂ →4CO₂ + 6H₂O
Combustion
Synthesis or Combination
Two or more elements combine to make one product.
A + B –> AB
Hydrogen
Group 1 Nonmetal
Percent Error
Titration
The process of adding a known amount of solution of known concentration to determine the concentration of another solution.
Group/Family Names
Calculate the volume required to prepare the diluted solution: Given 6.0M NaOH; need 5.0L of 0.10M NaOH.
M1V1 = M2V2
V1 = (M2V2)/(M1)
V1 = 0.083L
A cylinder contain a gas of volume 10 L, at a pressure of 80 kPa and a temperature of 200 K. Find the temperature of the gas which has a volume 20 L at a temperature of 220 K.
Vi = 10 L, Pi = 80 kPa, Ti = 200 K, Vf = 20 L, Tf = 220 kPa
Final Pressure(Pf) = PiViTf / TiVf
Pf= (80 x 10 x 220) / (200 x 20)
Pf = 44 kPa
Intramolecular Forces
Attractive forces WITHIN a molecule (Ionic & Covalent Bonds)
When adding and subtracting with Significant Figures, ___________________.
keep the least number of decimal places
Calculate the concentration of the solute in the diluted solution: 1.00mL of 0.50M NH4Cl diluted to 250.0mL
M1V1 = M2V2
M1 = (M2V2)/(V1)
M1 = (0.5 M x 1 ml)/(250 ml)
M1 = 0.0020M
Excess reagent/reactant
The reactant/reagant which is not completely used up during a reaction.
Subscript
Small numbers to the lower right of chemical symbols. Represent the number of atoms of each element in a molecule.
O₂
Significant Figure Rules for Multiplication and Division:?
The calculated answer can be no more precise than the least precise number from which the answer is derived.
The least precise number is the one with the fewest sig figs.
Products of an acid/base reaction
Salt + Water
Photon
Energy given off in the form of light by an excited electron. Otherwise known as a “quanta of light”.
Fission
Single Replacement
An element and a compound are located on each side of the equation. The element on the reactant side switches with the similarly charged ion within the compound on the reactant side.
A + BC –> AC + B
Convert 5.2L to quart.
1 gallon = 3.785 L
1 gallon = 4 quartds
Are zeros after a decimal and after a significant digit “significant” or “not significant”?
Significant
Amphoteric
Acid or Base
Chain Reaction
Polyatomic Ion
A group of atoms that acts like an ion (has a charge)
The Mole
A unit of measure.
1 mole = the atomic mass of an element
and
1 mole = 6.02 E23 atoms, particles, molecules, units, etc.
Lone Pairs
Electron pairs which are not involved in bonding. They do however, affect the shape because electron pairs repel other electron pairs.
pH Scale
pH = (-) log [H+]
pOH = - log [OH-]
pH + pOH = 14
[H+] = 2nd Log (-) pH
[OH-] = 2nd Log (-) pOH
[H+] [OH-] = 1E-14
Naming Covalent Compunds
You DO NOT use the “criss-cross” method. Use prefixes. The only time you do not use a prefix is when there is only one of the first nonmetal. Remember : 1-Mono 2-Di etc…
Solution
Solute + Solvent
What is the solubility of Potassium Nitrate at 50 C?
86 g Potassium Nitrate
Significant Figure Rules for Addition and Subtraction:?
The answer of a calculation based on measurements cannot have greater significance than any of the measurements that produced the answer.
The least certain measurement (fewest decimal places) limits the certainty of the calculated answer.
*Line up the decimal points and report the answer based upon the fewest decimal places.
Coefficients
The large numbers in front of chemical formulas. Represents the number of molecules of the substance.
2Al
How much more solute could I dissolve if I have 10g of Potassium Nitrate in 100g of Water at 30C?
~32g of Potassium Nitrate
Positive Exponents in Scientific Notation
Postive Exponents mean move the decimal to the right when changing a number to standard notation.
Electronegativity
Tendency of an atom to attract electrons to itself when it combines with another element.
Electronegativity increases from left to right across a period on the periodic table.
Electronegativiy decreases as you go down a group on the periodic table.
Percent Mass
Polar Covalent
A type of covalent bond between two atoms in which electrons are shared unequally. Because of this, one end of the molecule has a slightly negative charge and the other a slightly positive charge.
Balance the following chemical equation:
__Al₂(SO₄)₃ + __Ca(OH)₂ → __Al(OH)₃ + __CaSO₄
Al₂(SO₄)₃ + 3Ca(OH)₂ → 2Al(OH)₃ + 3CaSO₄
Write a chemical equation from the following word equation:
Sodium reacts with fluorine to form sodium fluoride
2Na + F₂–> 2NaF
Hund’s Rule
When filling sublevels other than s, electrons are placed in individual orbitals before they are paired up.
Electrons fill like people do on a bus. You would never sit right next to someone you do not know if there are free seats available, unless of course all the seats are taken then you must pair up.
So, when working with the p sublevel, electrons fill like this…up, up, up….down, down, down…
Nonmetals
To the right hand side of the periodic table (right of the zig zag line).
Not good conductors.
Low melting and boiling points.
Brittle.
VSPER
Valence Shell Electron Pair Repulsion
Most important aspect of determining the shape or geometry of a molecule. The molecule will adopt the shape which minimizes te electron pair repulsion.
Barometer
Measures atomospheric pressure.
To convert a number greater than 1 to scientific notation?
The original decimal point is moved n places to the left, and the resulting number is multiplied by 10^n.
Definition of a balanced chemical equation:
no atoms are lost or gained
the number of reacting atoms is equal to the number of product atoms
END POINT
When the indicator changes color.
Supersaturated
Contains more solute than it should at that temperature. Ussually the solution is heated to allow that much solute to dissolve and then cooled back down.
If you add solute to a supersaturated solution the “super” part (amount over the saturation point) will crystallize out of solution.
Actual Yeild
The amount of product which is actually formed when the reaction is carried out in the laboratory.
Predict the products of and write a balanced equation from the following statement:
H₂O₂ →
H₂O₂ → H₂ + O₂
DECOMPOSITION
Limiting Reagant/Reactant
Determines the amount of product that can be formed.
The reactant/reagant that is completely used up during a reaction.
(In the attached picture, beef patties are limiting how many hamburgers we can make.)
Rules for Writing Lewis Dot Structures
- Total the Valence Electrons and Update during each step.
- Form a single bond between the central atom and each surrounding atom (each bond uses two electrons).
- Place electrons around the outer atoms until you run out or they each have eight electrons around them. (Hydrogen and Helium can only have two electrons around them).
- Place any remaining electrons around the central atom.
- Does each atom other than hydrogen have eight electrons around it?
- Rearrange (share) electrons so that all atoms other than hydrogen have eight electrons around them.
9.08 g of Al₂0₃ is equal to how many moles?
9.08 g Al₂0₃ x (1 mole Al₂0₃/101.96 g Al₂0₃) = 0.0890 moles Al₂0₃
Molarity and Molality
Expressions of Concentration ( [] )
The amount of a component in a given area or volume.
What are the conversions between pressure units? (What amount of atm equals what amount of kPa, psi, torr, etc)
1 atm = 760 torr = 760 mmHg = 101.3 kPa
Acids
Electron acceptors.
Yeild H+ Ions in solution.
H+ donor.
Predict the products of and write a balanced equation from the following word statement:
Methane (C3H8) reacts with Oxygen gas to form __________.
Kinetic Molecular Theory of Gases
- Gases consist of tiny particles.
- These particles are so small, their volume can be assumed to be negligible (zero).
- The particles are in constant, random motion, colliding with the walls of the container. These collisions with the walls cause the pressure exerted by the gas.
- The particles are assumed not to attract or repel each other.
- The kinetic energy of the particles is directly proportional to the Kelvin temperature of the gas.
(As the temperature increases the energy increases)
How to calculate neutrons:
of Neutrons = Atomic Mass Number - Atomic Number
NaOH + HClO₄ →
NaOH + HClO₄ →NaClO₄+ H₂O Double Replacement
Subscripts
Small numbers to the lower right of chemical symbols. Represent the number of atoms of each element in a molecule.
0₂
Percent Composition
The amount of a given element in a compound.
In the equation:
2Na + Cl₂→ 2NaCl
How many moles of Na are needed if 285 g of NaCl are produced?
285g NaCl x (1 mole NaCl/ 58.5 g NaCl) x (2 moles Na / 2 moles NaCl) =
4.87 moles Na.
Predict the element formed and write a balanced nuclear equation for the following statement:
Uranium-238 decays by alpha emission to form __________.
Molality
m
Ionic Compounds
two words, first names cation second names anion. Indicate charge of transition metal cation by Roman Numeral. MgCl₂ = Magnesium Chloride Cr(NO₃)₃ = Chromium(III) Nitrate SnCl₂ = Tin(II) Chloride
Covalent/Molecular Bonding
Nonmetals SHARE electrons
Naming Ionic Bonds
State the name of the metal followed by the nonmetal with the ending changed to “ide”. If the metal is a transition metal, add a (Roman numeral). AlCl₃ = Aluminum Chloride CuCl₃ = Copper (III) Chloride
Polyatomic Ion
Polyatomic Ions ions made up of more than one atom; acts as an individual ion in a compound; charge applies to entire group of atoms.
Theoretical Yeild
The maximum amount of product that is CALCULATED to be formed from the given amounts of reactants.
Pauli Exclusion Principle
If there are two electrons in an orbital, they must have opposite (paired) spins.
Bond Pairs
Pairs of electrons which form a bond.
Valence Electrons
Electrons found on the outer energy level. Represented by Roman Numerals. Transition Elements do not have Roman Numerals which denote their valence electrons.
Greek Prefixes used in nomenclature 1= 2 = 3 = 4= 5 = 6= 7= 8= 9= 10=
1= mono 2 =di 3 =tri 4=tetra 5 = penta 6=hexa 7=hepta 8=octa 9=nona 10=deca
Unsaturated
Contains less solute than it can at that temperature.
C₄H₆ + O₂ →
2C₄H₆ + 7O₂ →4CO₂ + 6H₂O Combustion
Charles’ Law
The volume of a gas is directly proportional with the KELVIN temperature at a constant pressure.
V1T2 =V2T1
The pressure of a mixture of nitrogen, carbon dioxide, and oxygen is 150 kPa. What is the partial pressure of oxygen if the partial pressures of the nitrogen and carbon dioxide are 100 kPA and 24 kPa, respectively?
P = Pnitrogen + Pcarbon dioxide + Poxygen
150 kPa = 100 kPa + 24 kPa + Poxygen
Poxygen = 150 kPa - 100 kPa - 24 kPa
Poxygen = 26 kPa
Electron Configuration
A shorthand method of writing the location of electrons by sublevels.
Are zeros between significant digits “significant” or “not significant”?
Significant
Orbital
Sublevels can be broken down into regions called “orbitals”. An orbital is defined as the most probable location for finding an electron. Each orbital holds 2 electrons.
Molar Volume of a Gas
1 mole of any gas at STP = 22.4 Liters
How would you calculate the pH of a solution with a hydronium concentration of 1E-5 M?
pH = -log 1E-5 =5
What is the molarity of a solution made by dissolving 2.5g of NaCl in enough water to make 125 ml of solution?
According to _____________ law, pressure and volume are ______________ proportional provided all other factors remain constant. Mathematically, this means that their ____________ is a constant.
Boyle’s; inversely; temperature
Rules for Rounding Off Numbers?
- When the leftmost number removed is less than 5, the preceding number is left unchanged.
Ex: Round 45.2624 to four significant digits: 45.26
- When the leftmost digit removed is 5 or greater, the
preceding number is increased by 1.
Ex: Round 3.75 to two significant figures: 3.8
Half Life
The time it takes for the amount of a radioactive element to decay by half.
Rules for Adding and Subtracting with Significant Figures
The result has the same number of decimal places as the number with the fewest decimal places.
Write a chemical equation from the following word equation:
Magnesium reacts with oxygen to form magnesium oxide.
2Mg + O₂ –> 2MgO
Precipitate
Formation of a solid in a solution.
