DAT BC GC PT #4
Consider the following reduction half-reactions: Which of the following is the Eº cell for the reduction of chlorine?
The half-reaction for nickel has a negative E°, indicating that the reaction prefers to go in the reverse direction, getting oxidized. This half-reaction must be flipped, with an E° of 0.28. The half-reaction of the chlorine is positive, indicating that chlorine prefers the forward reaction, getting reduced. Calculate the E° cell: E° cell = E° cell reduction + E° cell oxidation E° cell = 1.36 + 0.28
To separate a homogeneous mixture of salt water, which of the following pieces of laboratory equipment is necessary? A. Buret (3%) B. Pipet (1%) C. Condenser (47%) D. Filter (29%) E. Separatory funnel (21%)
condenser Homogeneous mixtures are often separated using distillation. In distillation, the different boiling points of the substances are used to separate the mixture. The mixture is boiled, until one of the compounds evaporates. The evaporated compound is then immediately cooled through the condenser and collected on the other end in a flask. A. Buret. A buret is used during titration experiments to determine concentrations. B. Pipette A pipet is used for transferring substances of small volumes. D. Filter A filter would be used to separate a heterogeneous mixture. E. Separatory funnel A separatory funnel is useful for separating heterogeneous mixtures, like an organic solvent and aqueous solvent.
Which process would be used to separate two miscible liquids? A. Filtration (11%) B. Distillation (75%) C. Decantation (7%) D. Disproportionation (1%) E. Crystallization (7%)
distillation The two liquids can be boiled to separate them. Liquids that are able to mix in all proportions are said to be miscible. Miscible liquids form homogeneous mixtures that can only be separated by exploiting the differing chemical properties of the two liquids. A. Filtration Filtering or straining the homogeneous mixture would not help to separate the two liquids. C. Decantation Decantation is the process to remove the top layer of liquid after the precipitate has settled at the bottom. Decantation will not work because a precipitate is not present. D. Disproportionation In a disproportionation reaction, a substance is simultaneously oxidized and reduced, giving two different products. E. Crystallization In crystallization, a product is precipitated out, then is separated through filtration.
A solid compound that has a vapor pressure higher than atmospheric pressure will most likely be able to do which of the following? A. Melt (12%) B. Freeze (3%) C. Condense (4%) D. Vaporize (34%) E. Sublime (46%)
sublime If a solid compound has a high internal vapor pressure relative to the external environment, the compound will be able to sublime. The particles can turn into vapor without first transitioning into the liquid state. This is seen in dry ice. Dry ice has a higher vapor pressure than the atmosphere, thus as the dry ice "evaporates" the solid particles sublime.
Adding sodium oxalate to a solution of oxalic acid causes the pH to A. increase due to the common ion effect. (37%) B. decrease due to the common ion effect. (20%) C. remain constant because the resulting solution is a buffer. (15%) D. increase due to shifting the Ka. (18%) E. decrease due to shifting the Ka. (10%)
A. increase due to the common ion effect. We can represent this reaction with: HA ⇌ H+ + A- Where HA represents our acid (oxalic acid), H+ is a proton, and A- is the conjugate base (sodium oxalate, where sodium is just a spectator ion). Adding sodium oxalate adds more oxalate (the common ion) conjugate base (A-) to the solution. More A- on the right side of the equation pushes the reaction to the left. This consumes H+ in the process, decreasing H+ in the solution. Less H+ means the reaction is less acidic (more basic), meaning the pH has increased. Therefore, adding a common ion increases the pH. Another way to think about this question- we're adding a base to something. If you add a base, you increase the pH of the solution. C. remain constant because the resulting solution is a buffer. While it is true the resulting solution is a buffer, the initial solution is NOT a buffer. It was just oxalic acid. Adding sodium oxalate will increase the pH of this solution. If we add something else to the resulting solution, then the pH will tend to stay constant. D. increase due to shifting the Ka. E. decrease due to shifting the Ka. This is critical to remember, only temperature can change the Ka. Changes in concentration will not change the Ka. Ka stands for acid dissociation constant, therefore this value stays constant and only changes if you change the temperature.
Calculate the work done by an ideal gas on its surroundings when the gas is heated at constant pressure of 1 atm from volume 50L to 100L at 298K. A. 10 L•atm (6%) B. 100 L•atm (12%) C. -0.821 L•atm (9%) D. -150 L•atm (11%) E. -50 L•atm (62%)
-50 L•atm The work done when a gas is heated at constant pressure (isobaric) is: W = -P delta V = -P (V2-V1) Plug in the given values and solve: - 1 atm ( 100 -50) DAT Pro-Tip: Conceptually confirm that the answer should be negative. The gas is being heated, the volume is expanding, and that the system does work on its surroundings as it expands. When the system does work on the surroundings, work is negative and energy is lost. Alternatively, if the surroundings do work on the system, work is positive and the energy is gained.
A gas cylinder has an internal volume of 165 liters. How many moles of nitrous oxide are in the tank? Assume the apparatus is at sea level and the ambient temperature is 22° C.
1 x 165 / 0.082 x 295 Use the ideal gas law: PV = nRT Solve for the number of moles (n). The pressure (P) at sea level is 1 atmosphere. The volume (V) is given. There are two values for the constant (R), depending on the units for pressure: 0.082, used for atm, and 8.314, used for kPa. The temperature (T) must be converted to kelvin. 22° C equals 295° K.
What is the molar solubility of BaF2 (Ksp = 1.8 × 10-7) in 0.10 M sodium fluoride?BaF2(s) --> Ba2+(aq) + 2F-(aq)
1.8 x 10^-5M Write the balanced equation: Draw an ICE table Write the Ksp equation: Ksp = [Ba2+][F-]2 Fill in the values from the ICE table: Ksp = (x)(0.10 + 2x)2 Assume that the + 2x will not contribute substantially to the molar solubility because Ksp is <<< 1. Rewrite the Ksp equation and solve: Ksp = (x)(0.10)2 Ksp = 1.8 x 10-7 = (x)(0.10)^2 solve for x
When the following reaction is balanced in acidic solution using whole number coefficients, what is the coefficient of H+?CrO42- → Cr2O72-
2 Balance the equation to solve for the coefficient of H+: 1. Balance the chromium: 2CrO42- → Cr2O72- 2. Balance the oxygens by adding H2O: 2CrO42- → Cr2O72- + H2O 3. Balance the hydrogens by adding H+. Because this is in acidic solution, the H+ will be in the final half-reaction equation. 2H+ + 2CrO42- → Cr2O72- + H2O 4. Add electrons to balance the charges, as needed. In this case no electrons are needed. 2H+ + 2CrO42- → Cr2O72- + H2O
What is the pOH of a solution prepared by adding 20 mL of 0.02 M NaOH(aq) to 20 mL of water?
2 Use the dilution equation to find the new concentration of NaOH. Make sure to use 0.04 L for the second (final) volume. 0.02 L of NaOH(aq) is added to 0.02 L of water for a total new volume (V2) of 0.04 L. m1v1=m2v2 NaOH is a strong base and fully dissociates into Na+ and OH-. Because NaOH is a strong base, [OH-] = 0.01 M. Use the pOH equation to solve:
How many total electrons does Sn have in its p-subshells?
20 lectron configurations summarize the position of electrons in orbitals around an atom's nucleus. An electron can be placed in s, p, d, or f orbitals with each orbital having a different number of subshells, which hold 2 electrons each. In order to solve this problem, first write out the electron configuration for Sn: 1s22s22p63s23p64s23d104p65s24d105p2 Notice that each p-orbital can hold a maximum of 6 electrons, count the total number of electrons in each p-orbital: 2p6 → 6 electrons 3p6 → 6 electrons 4p6 → 6 electrons 5p2 → 2 electrons Sn has a total of 20 electrons in p-subshells. Key Takeaway: Electrons can be placed in s, p, d, or f orbitals. Each orbital has a different number of subshells, with each subshell containing 2 electrons.
10 mL of 1 M salt water is added to 40 mL of water. What is the relative concentration of salt in the new solution? A. 10% (5%) B. 20% (45%) C. 25% (34%) D. 40% (13%) E. 50% (3%)
20% Let's begin by using the dilution formula to find the molarity of the diluted (new) solution. We should be aware that 40 mL of water is being added to 10mL of the original solution, giving us a new volume of 10 mL + 40 mL = 50 mL. M1V1 = M2V2 (1 M) (10 mL) = M2 (50 mL) M2 = (1 M) (10mL) / (50 mL) M2 = 0.2 M DAT Pro-Tip: M (molarity) has units mol/L. In this case, we didn't convert 10 and 50 mL to L because the units cancel out. This saves time and simplifies the math (vs. dividing decimals e.g. 0.01 and 0.05 L). Both will give you the same answer whether you use mL or L. Now, let's compare the new molarity to the old molarity. (0.2 M) / (1 M) * 100% = 20% In other words, the new molarity of 0.2M is 20% of our old molarity of 1M. Key Takeaway: To find the relative percent concentration of solute in a diluted solution, divide the new molarity by the old molarity, then multiply by 100. Make sure to use the new total volume of the solution to perform this calculation.
What is the maximum number of electrons that can be held in the fourth energy level? A. 2 (2%) B. 8 (15%) C. 10 (12%) D. 14 (25%) E. 32 (45%)
32 The fourth energy level has four orbitals: s, p, d, and f. The s orbital can hold a maximum of 2 electrons, the p orbital can hold a maximum of 6 electrons, the d orbital can hold a maximum of 10 electrons, and the f orbital can hold a maximum of 14 electrons. The fourth energy level can hold at most 2 + 6 + 10 + 14 = 32 electrons.
What is the mass percent of methanol in a solution prepared by diluting 16 grams of methanol with 32 grams of water? A. 8% (1%) B. 16% (4%) C. 25% (9%) D. 33% (62%) E. 50% (24%)
33% The formula for mass percent is: grams solute / grams solution x 100% Plug in the values given: 16 / 16 + 32 x 100 = 33
Rank the following acids from lowest pKA to highest pKA: I. HF II. HCl III. HBr IV. HI
4 3 2 1 Ka is the equilibrium constant of an acid. If Ka is less than 1, then the acid is considered very weak and does not dissociate highly. A large Ka means the acid is very strong. pKa is the negative log of Ka, which is just used to make the numbers a bit simpler. The smaller the pKa, the stronger the acid. Therefore, ranking the acids from LOWEST to HIGHEST pKa is the equivalent of ranking acids from STRONGEST to WEAKEST acid. Acid strength depends on the strength of the H−X bond. The weaker the bond, the more easily H+ can be formed, the stronger the acid. Atoms get larger down a group (vertical column) of the periodic table, which means that the strength of the bond gets weaker. As the strength of the bond gets weaker, the acids strength gets stronger. Therefore looking at the periodic table, we'd expect HI to be the strongest acid (I has the largest atomic radius of the options), and HF to the weakest acid (F has the smallest atomic radius of the options). [Lowest pKa = strongest acid] HI < HBr < HCl < HF [Highest pKa = weakest acid] Key Takeaway: Hydrogen halides (ex. H-I) get stronger as you move down the halogen column on the periodic table as the atomic radius gets bigger which makes the bond weaker
What is an activated complex? A. A molecule that fully dissociates in solution. (3%) B. A molecule that contains electrically neutral groups of atoms held together by covalent bonds. (6%) C. A molecule that contains unpaired electrons in the molecular orbital diagram and is attracted to a magnetic field. (22%) D. An unstable arrangement of atoms that exists momentarily at the peak of the activation energy barrier. (69%)
An unstable arrangement of atoms that exists momentarily at the peak of the activation energy barrier. A reaction coordinate diagram shows the amount of energy a reaction must traverse in order to convert the reactants into products. An activated complex, also known as a transition state, is an unstable, high-energy state that briefly exists between a reactant and intermediate, or between a reactant and product. It exists at the peak of the hill in the reaction coordinate diagram. A. A molecule that fully dissociates in solution. Strong acids and bases are molecules that fully dissociate in solution. B. A molecule that contains electrically neutral groups of atoms held together by covalent bonds. Molecules contain electrically neutral groups of atoms held together by covalent bonds. C. A molecule that contains unpaired electrons in the molecular orbital diagram and is attracted to a magnetic field. Paramagnetic atoms contain unpaired electrons in the molecular orbital diagram and are attracted to a magnetic field.
Which of the following is an example of a compound that has polar bonds but is non-polar overall? A. SO2 (12%) B. H2O (6%) C. N2 (5%) D. CF4 (64%) E. NH3 (13%)
CF4 Molecular polarity depends on the shape of the molecule. Draw the Lewis structure for each answer choice to determine the overall shape. Draw an arrow towards the more electronegative atom in each bond, and ask yourself whether the truck would move in the mud. A. SO2 B. H2O E. NH3 CF4 and N2 are the only compounds that are molecularly non-polar, and would not move in the mud. In bond polarity, if there is a large difference in the electronegativities of the elements that make up a bond, then the elements are most likely sharing the electrons in the bond unequally, resulting in a polar bond. C. N2 In N2, the N-N bond is non-polar. In CF4, the C-F bonds are polar because C and F's electronegativities are not equal. CF4 has polar bonds but is non-polar overall.
Which of the following transformations has ΔS < 0? A. CO2(s, -78.5 oC, 1 atm) → CO2(g, -78.5 oC, 1 atm) (7%) B. CO2(s, -100 oC, 1 atm) → CO2(s, -200 oC, 1 atm) (73%) C. CO2(l, -23 oC, 6 atm) → CO2(g, -23 oC, 6 atm) (6%) D. CO2(g, 30 oC, 1 atm) → CO2(g, 40 oC, 1 atm) (14%)
CO2(s, -100 oC, 1 atm) → CO2(s, -200 oC, 1 atm) Entropy decreases (ΔS < 0) with a decrease in temperature, decrease in volume (which is an increase in pressure) or decrease in the number of gas particles. CO2(s, -78.5 oC, 1 atm) → CO2(g, -78.5 oC, 1 atm) - phase change from solid to gas: ΔS > 0 CO2(s, -100 oC, 1 atm) → CO2(s, -200 oC, 1 atm) - temperature has decreased: ΔS < 0 CO2(l, -23 oC, 6 atm) → CO2(g, -23 oC, 6 atm) - phase change from liquid to gas: ΔS > 0 CO2(g, 30 oC, 1 atm) → CO2(g, 40 oC, 1 atm) - temperature has increased: ΔS > 0
Consider the following chemical reactions. What is the total enthalpy for the equation:
E. (-1)(-242) + (-2)(-286) Hess's law states that the total enthalpy (ΔH) of a reaction is the sum of the individual ΔH's of the reaction's intermediate steps. DAT Pro-Tip: Both steps have H2O, however, the subscripts (l) and (g) represent the states of water. These waters are considered different for ΔH because one is in liquid form and the other is in gaseous form. Change the two steps as necessary to produce the final equation. The ΔH of a step must be multiplied by -1 when reversing an equation. The ΔH of a step must be multiplied by 2 when multiplying the coefficients in the equation by two. This produces the overall reaction: Calculate the ΔHrxn: ΔHrxn = (-1)(-242) + (-2)(-286)
Which of the following compounds would have Lewis dot diagrams constructed with the same number of valence electrons as NH4+? A. NO3- (10%) B. H2O (54%) C. CN- (14%) D. SO3 (9%) E. BF3 (13%)
H2O The ammonium ion, NH4+, has five valence electrons from the nitrogen, and one valence electron from each of the four hydrogens. The "+" indicates that one valence electron was lost. The total number of valence electrons in NH4+ is: 5 + 4 - 1 = 8. The only compound that also has eight valence electrons is H2O, with six valence electrons from the oxygen, and one valence electron from each of the two hydrogens.
Place the following elements in order of DECREASING ionization energy: Si, He, F, Cs
He F Si Cs Ionization energy is the energy needed to remove an electron. Ionization energy increases towards the top right of the periodic table. He has the highest ionization energy of options, at the top right of the periodic table. Caesium has the lowest ionization energy of the options, at the bottom left of the periodic table.
A real gas is most likely to exhibit ideal gas behavior under which of the following conditions?
High temperature and low pressure The assumptions we make when classifying a gas as an 'ideal gas' are: 1. The volume or size of each individual gas molecule is insignificant. 2. Gas molecules' collisions with each other are perfectly elastic. No intermolecular forces. 3. The average kinetic energy of a gas depends only on the system's temperature. So in order to get our real gas to exhibit ideal gas behavior, we want to make it so the volume or size of each individual gas molecule is insignificant compared to the volume of the container the gas is in. So what conditions could we impose to achieve this requirement? Well, we can't decrease the volume of the gas molecules themselves, but we can increase the volume of the container to make the volume of the gas molecules insignificant! According to Boyle's Law, volume and pressure have an inverse relationship, so if we wanted to increase the volume of the container we need to decrease the pressure. Therefore, at low pressures we can increase the volume of the container so as to make the volume of the gas molecules themselves more negligible. This gets us closer to having ideal gas behavior. Now for the second assumption, what does it mean to have the collisions between gas molecules be perfectly elastic? Well, if there are intermolecular forces between two gas molecules, then when they collide they will want to stick together through those electrostatic interactions. This is why we need there to be no intermolecular forces between the gas molecules. We want the molecules to bounce right off each other in the event of a collision. So how could we manipulate our conditions to achieve perfectly elastic collisions? At high temperatures, molecules have high kinetic energy and will be moving very rapidly in the container. If they are moving more rapidly there will be less of a chance of a "sticky" collision between molecules due to intermolecular forces. Thus, increasing the temperature would create more elastic collisions between gas molecules. Choice [B] suggests having high temperatures and low pressures in order to get our real gas to behave more closely with an ideal gas, and is, therefore, our correct answer.
KClO is dissolved in water. Which of the following reaction equations represents what is taking place throughout the solution? KClO → K+ + ClO- ClO- + H2O ⇌ HClO + OH- ClO- + H2O ⇌ HClO + H3O+ H2O ⇌ H+ + OH- A. I only (7%) B. I and IV only (11%) C. I and III only (10%) D. I, III, and IV only (9%) E. I, II, and IV only (63%)
I, II, and IV only This is a multi-step question that tests your integration of solubility rules and acid-base equilibria. Recall that ionic compounds with group 1 metal cations are soluble, meaning they will completely dissociate into their constituent ions in water. Solubility of Ionic Compounds in Water 1. Most Group 1 metal cations, NO3-, ClO4-, C2H3O2-, and NH4+ salts are soluble. 2. Most Ag+, Pb2+, S2-, OH-, Hg22+, CO32-, and PO43- salts are insoluble. 3. The solubles generally trump the insoluble. I. KClO → K+ + ClO- KClO, when placed into water, will completely dissociate into K+ and ClO- ions, aligning with reaction [I]. II. ClO- + H2O ⇌ HClO + OH- Now, looking at ClO-, recall that charged compounds will react with H2O, which is polar. In this case, the negatively charged hypochlorite ion will react with H2O, stripping away H+ to form HClO and OH-. Now, recalling our strong acids and bases, hypochlorous acid is not a strong acid, meaning it will partially dissociate in water back into its conjugate base, ClO-. Strong Acids and Bases 1. Strong acids: HI, HBr, HCl, HClO3, HClO4, H2SO4, HNO3 2. Strong bases: Group 1 metal hydroxides, Mg(OH)2, Ca(OH)2, Sr(OH)2, Ba(OH)2 The formation and subsequent dissociation of HClO is represented by reaction [II]. IV. H2O ⇌ H+ + OH- Water can and does react with itself, spontaneously forming H3O+ and OH-. This is called autoionization of water and is represented by reaction [IV]. The complete dissociation of KClO, acid-base equilibria of ClO- and HClO, and autoionization of water. Key Takeaway: When KClO is placed in water, it completely dissociates into K+ and ClO-. ClO-, as the conjugate base of HClO, will react with water to form HClO and subsequently partially dissociate back into H+ and ClO-. Water spontaneously autoionizes into H+ and OH-.
Which of the following would be the empirical formula of a compound that has 4 moles of oxygen and 10 moles of nitrogen? A. N2O (3%) B. N2O4 (4%) C. N5O2 (88%) D. N10O4 (4%)
N5O2 To find the empirical formula of the given compound, calculate the mole ratio between the nitrogen and oxygen by dividing by the lower mole number (4 moles of oxygen): 4/4 moles of oxygen = 1 mole oxygen 10/4 moles of nitrogen = 2.5 mole nitrogen This produces the empirical formula N2.5O. Elements combine to form compounds using whole number ratios, so multiply the subscripts by 2, resulting in N5O2. Key Takeaway: If an empirical formula calculation yields a decimal number, multiply the subscripts by the same number until a whole number ratio is obtained.
Which best describes an isotope? A. Same number of neutrons, but different number of protons (5%) B. Same number of neutrons, but different number of electrons (2%) C. Same number of protons, but different number of electrons (12%) D. Same number of protons, but different number of neutrons (82%)
Same number of protons, but different number of neutrons The atomic mass of an element is approximately equal to the number of protons and neutrons in the atom. The atomic number of an element is equal to the number of protons in the atom. The atomic number defines the identity of the atom (what element it is). Isotopes are two or more types of atoms that have the same atomic number but different atomic mass. Because the atomic number (and identity of the atom - what element it is) is defined by the number of protons, the proton number can't change. If the proton number changed, we'd be looking at a different element. Therefore, for mass to change without atomic number changing: isotopes have the same number of protons, but different numbers of neutrons. Key Takeaway: Isotopes are two or more types of atoms that have the same atomic number but different atomic mass. Isotopes have the same number of protons, but different numbers of neutrons.
Why does a nucleus weigh less than the sum of its neutrons and protons? A. Neutrons have negligible mass (11%) B. Some of the nucleus's mass is converted into nuclear binding energy (58%) C. The repulsive force between the protons and neutrons decreases the mass of the nucleus (17%) D. The combined mass of an atom's electrons is subtracted to determine nuclear mass (9%) E. Atoms in nature have lower masses due to long-term radioactive decay (6%)
Some of the nucleus's mass is converted into nuclear binding energy Recall that all atoms must expend a certain amount of energy to keep their nuclei intact, which can be referred to as nuclear binding energy. We can also define nuclear binding energy as the amount of energy required in order to separate a nucleus into its constituent protons and neutrons. The source of this energy is actually the nucleus itself, which uses mass as energy according to Einstein's famous equation: E = mc2. Because mass is directly converted into energy, nuclear binding energy results in a mass defect, which means that the nucleus is not quite as heavy as the combined mass of the nucleus' protons and neutrons. A. Neutrons have negligible mass The mass of a nucleus includes both the neutrons and protons that make up the nucleus, which both hold a roughly equivalent mass. C. The repulsive force between the protons and neutrons decreases the mass of the nucleus. Protons and neutrons do not exert repulsive forces on each other. Neutrons, by definition, are neutral, meaning they do not interact electronically with other subatomic particles. D. The combined mass of an atom's electrons is subtracted to determine nuclear mass. Electrons are not involved with the calculation of nuclear mass, as they do not reside in the nucleus. E. Atoms in nature have lower masses due to long-term radioactive decay. Although this sounds plausible, even if all parts of this statement were true, it does not answer the question stem. Key Takeaway: Mass defect in nuclei is a direct result of the conversion of some nuclear mass to energy, called nuclear binding energy.
If a liquid is found to have weak intermolecular forces, then that liquid will generally have a A. low volatility. (16%) B. low viscosity. (76%) C. high density. (2%) D. high boiling point. (3%) E. high surface tension. (3%)
low viscosity viscous - think honey and maple syrup B. low viscosity. The viscosity is the resistance to flow. Weak intermolecular forces lead to a low viscosity because the particles are less attracted to one another. A. low volatility. Volatility is a liquid's readiness to evaporate. A liquid with low intermolecular forces will evaporate easily, and have high volatility. C. high density. Density is not related to intermolecular forces. D. high boiling point. Weak intermolecular forces lead to a low boiling point. E. high surface tension. The stronger the intermolecular forces, the higher the surface tension.
Which of the following elements reacts explosively with water? A. Lead (7%) B. Iodide (10%) C. Potassium (67%) D. Hydrogen (5%) E. Argon (12%)
potassium The group 1 elements, alkali metals, react vigorously with water to produce hydrogen gas. The group 2 elements, alkaline earth metals, also react with water. However, they do not react as vigorously as the alkali metals.
In the reaction 2X + Y → X2Y, X is second order and Y is zero order. What would we expect to occur if [X] is tripled and [Y] is doubled?
rxn incre by factor of 9 Evaluating 2X + Y → X2Y with X being second-order and Y being zero-order, we can begin this problem by completely leaving out Y since changing the concentration of Y would have no effect on the overall rate of the experiment. We are now left with evaluating the effect of increasing the concentration of X. Understanding the experiment is second-order overall, we then can interpret that the rate is proportional to the square of the concentration. Rate = [X]2, and we triple the concentration of X so Rate = [3X]2 = 9X2. So, if we triple the concentration of X, we multiply the rate by nine.
What are the units of the rate constant for the integrated rate law graph?
s-1 the graph was Ln concen on y-axis on DAT BC A general set of rules for finding the integrated rate law graphs for ordered reactions: Zero-order reactions give a straight line with negative slope for the [concentration] vs. time graph: Slope = -k (units: M1s-1) Example rate law: Rate = k First-order reactions give a straight line with negative slope for the ln[concentration] vs. time graph: Slope = -k (units: s-1) Example rate law: Rate = k[A] Second-order reactions give a straight line with positive slope for 1/[concentration] vs. time graph: Slope = k (units: M-1s-1) Example rate law: Rate = k[A]2
