kb of koh kb of koh

0000000751 00000 n . Once this reaction reaches equilibrium, we can write an equilibrium expression and we're gonna consider If you think about the It should be noted that this is a homogenous equlibria, and although we are ignoring the water and treating it as a liquid, it is for a different reason than was used in the last chapter for heterogeneous equilibria. We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. a plus one formal charge and we can follow those electrons. https://www.thoughtco.com/calculating-ph-of-a-strong-base-problem-609588 (accessed May 2, 2023). - GRrocks. It is always harder to remove a second proton from an acid because you are removing it from a negative charged species, and even harder to remove the third, as you are removing it from a dianion. So, just like the acids, the trait is that a stronger base has a lower pKb while the Kb increases with the acid strength. This method of producing potassium hydroxide remained dominant until the late 19th century, when it was largely replaced by the current method of electrolysis of potassium chloride solutions. All right, so let's use We will use K (a or b) to represent the acid or base equilibrium constant and K' (b or a) to represent the equilibrium constant of the conjugate pair. Buffer solution pH calculations (video) | Khan Academy anion is not very good at accepting them. General Kb expressions take the form Kb = [BH+][OH-] / [B]. If we think about trailer BPP Marcin Borkowskiul. We typically write theacid dissociation as: Noting that water is omitted andhydronium is written as H+(implicitly meaning H3O+and not a free proton). equilibrium expression. 0000001472 00000 n Thus, the solution of 0.25 M Ca(OH)2 will contain 0.25 M Ca2+, and 0.50 M OH ions because each mole of Ca(OH)2 ionizes to one mole of Ca2+ and 2 moles of OH ions: All alkali metal and alkaline earth metal oxides, except BeO which is amphoteric, are basic as well because their reaction with water produces the corresponding hydroxide. Ka = [H3O +][A ] [HA] Another necessary value is the pKa value, and that is obtained through pKa = logKa. If you're seeing this message, it means we're having trouble loading external resources on our website. concentration of A minus, so times the concentration of A minus. BOH B + + OH . " The following bases are listed as strong: In textbooks where this idea is discussed, one often sees this statement about the Kb of a strong base. The acid and base chart is a reference table designed to make determining the strength of acids and bases simpler. So we follow a similiar calculation as that of the weak acid, but now we are calculating [OH-] and not [H+]. Water, H2O accepted a proton, so this is our Bronsted-Lowry base and then once H2O accepts a proton, we turn into hydronium H3O plus. as a Bronsted-Lowry acid and donate a proton to Type Formula K sp; Bromides : PbBr 2: 6.3 x 10-6: AgBr: 3.3 x 10-13: Carbonates : BaCO 3: 8.1 x 10-9: CaCO 3: 3.8 x 10-9: CoCO 3: 8.0 x 10-13: CuCO 3: 2.5 x 10-10: FeCO 3: 3.5 x 10-11: PbCO 3: 1.5 x 10-13: MgCO 3: 4.0 x 10-5: MnCO 3: 1.8 x 10-11: NiCO 3: 6.6 x 10-9: Ag 2 CO 3: 8.1 x 10-12: ZnCO 3: 1.5 x 10-11: Chlorides What is the pH after 25.00 mL of HCl has been added? Here you are going to find accommodation mostly in bigger resorts. So this is the acid ionization constant or you might hear acid Question = Is SCl6polar or nonpolar ? All right and we know when we're writing an equilibrium expression, we're gonna put the concentration of products over the concentration of reactants. KOH, like NaOH, serves as a source of OH, a highly nucleophilic anion that attacks polar bonds in both inorganic and organic materials. Aqueous potassium hydroxide is employed as the electrolyte in alkaline batteries based on nickel-cadmium, nickel-hydrogen, and manganese dioxide-zinc. left with the conjugate base which is A minus. So pKa is equal to 9.25. All right, so here we have Bronsted-Lowry. Which species are conjugate acid/base pairs? All right, so let's go back up here. In this weakened state, the hair is more easily cut by a razor blade. What Is the Kb of NaOH? - Reference.com For example, the pKbof ammonia and pyridine are: pKb(NH3)= log Kb = log 1.8 x 10-5=4.75, pKb(C5H5N)= log Kb = log 1.7 x 10-9= 8.77. Othewise we need to solve the quadratic equation, \[ [H^+] =[HA^-] = \sqrt{k_{a1}[H_2A]_i}\], From K2we can calculate A-2as [H+] = [HA-] and they cancel, \[K_2=\frac{\cancel{[H^+]}[A^{-2}]}{\cancel{[HA^-]}} \\ \; \\ so \\ \; \\ [A^{-2}]=K_2\], and we can get hydroxide from the water ionization constant K_w, \[K_w=[H^+][OH^-] \\ \; \\ so \\ \; \\ [OH^-]=\frac{K_w}{[H^+]}\]. In food products, potassium hydroxide acts as a food thickener, pH control agent and food stabilizer. Only the [OH] from the excess KOH is to be counted. Potassium Hydroxide or KOH, is a strong base and will dissociate completely in water to K+ and OH-. Here are some of the values of weak and strong acids and bases dissociation constants used by BATE when calculating pH of the solution and concetrations of all ions present. Forming this bond that we get H3O plus. To do that you use, \[K_a = \dfrac{[H_3O^+][A^-]}{[HA]} \label{2} \], Another necessary value is the \(pK_a\) value, and that is obtained through \(pK_a = {-logK_a}\), The procedure is very similar for weak bases. Marked out of 10.00 Answer: P Flag question Question 27 Not yet answered Calculate the solubility (in mol/L and g/L) of PbSO4(s) For the definitions of Kan constants scroll down the page. write 1.23e4 for 1.23x10^). [18] The nickelmetal hydride batteries in the Toyota Prius use a mixture of potassium hydroxide and sodium hydroxide. Accessibility StatementFor more information contact us atinfo@libretexts.org. Cl- is a weaker base because Cl is very electronegative and will be unwilling to accept a proton to share its electrons, instead it would prefer to keep the electrons for itself. Generally speaking, these values are not used in calculations since, at common concentrations in chemistry, each substance is 100% dissociated. There is significantly less information on Kb values for common strong bases than there is for the Ka for common strong acids. [10] The high solubility of potassium phosphate is desirable in fertilizers. You use the formula, \[K_b = \dfrac{[B^+][OH^-]}{[BOH]} \label{4} \], The \(pK_b\) value is found through \(pK_b = {-logK_b}\). Now lets look at 0.0001M Acetic Acid. Let me show those electrons. move off onto the chlorine, so let's show that. All right, so this electron this acid base reaction would just be to write out H2O plus HCL, gives us H3O plus, plus CL minus. Legal. Therefore: HI (aq) + KOH(aq) H2O(l) + KI (aq) Acetate ion is a weak base, but it's a better base than its conjugate acid (acetic acid) is. change and so we leave, we leave H2O out of our JywyBT30e [` C: Monoprotic acid/base corresponds to the donation/acceptance of, Polyprotic acid/base corresponds to the donation/acceptance of. You then obtain the equation Kb = Kw / Ka. pH=5.86 The net ionic equation for the titration in question is the following: CH_3NH_2+H^(+)->CH_3NH_3^(+) This exercise will be solved suing two kinds of problems: Stoichiometry problem and equilibrium problem . When we write the equilibrium expression, write KA is equal to the Molten KOH is used to displace halides and other leaving groups. That's gonna give this oxygen Is LiOH a weaker base than NaOH? - Chemistry Stack Exchange in the electrons in green and let me go ahead and We could solve all these problems using the techniques from the last chapter on equilbria, but instead we are going to develop short cut techniques, and identify when they are valid. - potassium hydroxide KOH - lithium hydroxide LiOH - rubidium hydroxide RbOH . "Acids and Bases - Calculating pH of a Strong Base." 0000022537 00000 n 0000003396 00000 n basic A 30.00 mL sample of 0.125 M HCOOH is being titrated with 0.175 M NaOH. the weaker the conjugate base. Using the equation \(K_{a2} = \dfrac{[H_3O^+][SO_4^2-^-]}{[HSO_4^-]}\), \(K_{a2} = 1.1 * 10^-2\), and an ICE Table to get \(x^2 + .0.0205x - 0.0001045 = 0\). concentration of your product so CH3COO minus times the concentration of H3O plus, all over the concentration of acetic acid because we leave water out. Once again let's follow But first, we need to define what are equilibrium constants for acid base reactions. The potassium ion is a spectator. How to calculate the pH of the neutralisation of HCN with excess of KOH? electrons in the auction is going to take this acidic proton, leaving these electrons bonded to three hydrogens. Except where otherwise noted, data are given for materials in their, Catalyst for hydrothermal gasification process, Rmpp Chemie-Lexikon, 9th Ed. So we make hydronium H30 plus and these electrons in green right here are going to come off onto If you were to do the recipricol of the ka (i.e. Who are the experts? Posted 8 years ago. So, just like the acids, the trait is that a stronger base has a lower pKb while the Kb increases with the acid strength. Now we need to solve for the necessary concentrations, \([H_2S0_4]\) = 0 (because the first ionization reaction went to completion), \([HS0_4^-]\) = \(k_{a1}\) - \(k_{a2}\) = 9.50*10-3 M - 0.004226 M = 5.27*10-3 M, \([H_3O^+]\) = \(k_{a1}\) + \(k_{a2}\) = 9.50*10-3 M + 0.004226 M = 1.37*10-2 M. Assuming that the [H30+] is the same for all the ionizations. Here is a list of important equations and constants when dealing with \(K_a\) and \(K_b\): \[HA_{(aq)} + H_2O_{(l)} \rightleftharpoons H_3O^+_{(aq)} + A^-_{(aq)} \label{1} \], you need to solve for the \(K_a\) value. Just like the strong acids, we recognize them by their ability to completely ionize in aqueous solutions. Hulanicki, Adam. one arrow down over here. Expert Answer. He holds bachelor's degrees in both physics and mathematics. Direct link to Dan Donnelly's post Water is usually the only, Posted 6 years ago. And one way to think about that is if I look at this reaction, So we could write that And so we could think about this acid base reaction would be just to write In many textbooks, the above values are never discussed and the author will often write this about the Ka of a strong acid: And the exact values are never discussed. So this is just a faster way of doing it and HCL is a strong acid. It is deliquescent, often appearing as a damp or wet solid. Noting that \(x=10^{-pH}\) (at equilibrium) and substituting, gives\[K_a =\frac{x^2}{[HA]_i-x}\], Now by definition, a weak acid means very little dissociates and if x<< [HA]initialwe can ignore the x in the denominator. New York, NY: Ellis Horowood Limited, 1987. So concentration of our products times concentration of CL minus, all over, right, we have HCL and we leave out water. Ka of HCOOH = 1.8 104 2.32 A 20.00 mL sample of 0.150 M NH3 is being titrated with 0.200 M HCl. concentration of hydronium H3O plus times the 0000001177 00000 n Solving for the Kb value is the same as the Ka value. CDC - NIOSH Pocket Guide to Chemical Hazards, https://en.wikipedia.org/w/index.php?title=Potassium_hydroxide&oldid=1152475114, Short description is different from Wikidata, Pages using collapsible list with both background and text-align in titlestyle, Articles containing unverified chemical infoboxes, Creative Commons Attribution-ShareAlike License 3.0, This page was last edited on 30 April 2023, at 13:17. Direct link to varun's post Why is cl- a weaker base, Posted 8 years ago. Now acetic acid is a So the negative log of 5.6 times 10 to the negative 10. And so we write our equilibrium constant and now we're gonna write The base dissociation constant, or Kb, of sodium hydroxide, or NaOH, is approximately 1020. So lone pair of electrons on the oxygen pick up this proton leaving They are all defined in the help file accompanying BATE. NaOH is a strong base that completely ionizes or dissociates into Na and OH-ions in a solution. So we get 100% ionization. approximately 100% ionization, we have all products here. be our Bronsted-Lowry acid and this is going to be the acidic proton. These as well, are types of acid-base reactions where the base is the oxide ion (O2-) and water is the acid. In textbooks where this idea is discussed, one often sees this statement about the K b of a strong base: K b >> 1. The smaller the pKb, the stronger the base. This acid-base chart includes the K a value for reference along with the chemical's formula and the acid's conjugate base. the forward reaction and the stuff on the Potassium hydroxide is an inorganic compound which is denoted by the chemical formula KOH. off of a generic acid HA. (Kb of NH is 1.80 10). about the reverse reaction, the chloride anion would be So all over the Answer = C2Cl2 is Polar What is polarand non-polar? Kb= [HCN] [OH]/ [CN] The contribution of the [OH] coming from the hydrolysis of the cyanide can be ignored. Aqueous KOH saponifies esters: When R is a long chain, the product is called a potassium soap. We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. extremely high value for your KA. We're gonna think about Potassium hydroxide, SIDS Initial Assessment Report For SIAM 13. Aside from these, the carbonates (CO32-) and bicarbonates (HCO3) are also considered weak bases. As someone who has to write intricate Excel worksheets for preparing buffers at our company, this program [Buffer Maker] seems amazing. Remember that diprotic acids donate protons stepwise and there is an amphoteric intermediate HA-, so in the reaction of a diprotic acid there are 5 chemical species, H2A, HA-, A-2, H+and OH-. [21] Entomologists wishing to study the fine structure of insect anatomy may use a 10% aqueous solution of KOH to apply this process.[22]. For an Acid Base Conjugate Pair. Here is how to perform the pH calculation. If you think about what Acid and Base Chart Table of Acids & Bases - Sigma-Aldrich 0000002830 00000 n that does for your KA, that's gonna give you an at this acid base reaction. Acetate (CHCOO-) isn't a strong base. Solved Question 26 Not yet answered Calculate the pH of a - Chegg our equilibrium expression. Since both of these concentrations are greater than 100Ka, we will use the relationship, \[\% I = \frac{[A^-]}{[HA]_i}(100) = \frac{[\sqrt{K_a[HA]_i}]}{[HA]_i}(100)\], \[ \% I= \frac{\sqrt{1.8x10^{-5}[1.0]}}{[1.0]}(100) = 0.42%\], \[ \% I= \frac{\sqrt{1.8x10^{-5}[0.01]}}{[0.01]}(100) = 4.2%\]. Like any equilibrium reaction, the larger the equilibrium constant, the more the reaction is shifted to the right. Because of its high affinity for water, KOH serves as a desiccant in the laboratory. Potassium hydroxide - Wikipedia Ksp Table - UMass this proton to form this bond, so we form H3O plus or hydronium. Then you use the quadratic equation to solve for X, to get \(x\) = 0.004226. For the definitions of Kbn constants scroll down the page. Robert E. Belford (University of Arkansas Little Rock; Department of Chemistry). KOH is an example of a strong base, which means it dissociates into its ions in aqueous solution. So these two electrons in red here are gonna pick up this Also, I'm curious as to what the formula for KB is. The equation of the second ionization is \(HSO_4- + H_2O \rightleftharpoons H_3O^+ + SO_4^2-\). The larger theKb, the stronger the base. Thus on a molar basis, NaOH is slightly more soluble than KOH. It is incorrect because the arrow shows the movement of electrons. Legal. How do you calculate the pH at the equivalence point for the titration Are there other noteworthy solvents that don't get included in the Ka equation aside from water? Let's write our equilibrium expression. This idea of proton donor and proton acceptor is important in understanding monoprotic and polyprotic acids and bases because monoprotic corresponds to the transfer of one proton and polyprotic refers to the transfer of more than one proton. When the electrons from water are donated to the hydrogen, is it wrong to think that the hydrogen is attracted to lone pair? For example, in a process commonly referred to as "chemical cremation" or "resomation", potassium hydroxide hastens the decomposition of soft tissues, both animal and human, to leave behind only the bones and other hard tissues. Look at the KA value. of our reactant, so we have HA over here, so we have HA. We form the chloride anion. Potassium carbonate is mainly used in the production of soap and glass. Potassium hydroxide is often the main active ingredient in chemical "cuticle removers" used in manicure treatments. Titration of a Strong Acid With A Strong Base - Chemistry LibreTexts Nope! This is what we also saw when introducing thepHto quantify the acidity of the solution. 0000008268 00000 n Before completing this section we want to look at the effect of dilution on percent ionization and our rule of thumb that we can ignore the extent of dissociation when [HA]i>100Ka. Direct link to Ayan Gangopadhyay's post Cl- is a weaker base beca, Posted 8 years ago. The Kb values of the most common weak bases are listed in the table below: Notice that allKbvalues are very small which makes it inconvenient for certain calculations or quickly tell which base is stronger or weaker. Bern, Switzerland, 6-9 November 2001. 0000000016 00000 n 1st step. what that does to the KA, all right, a very small number divided by a very large number, this The potassium salts of carbonate, cyanide, permanganate, phosphate, and various silicates are prepared by treating either the oxides or the acids with KOH. The acid dissociation constant, signified by \(K_a\), and the base dissociation constant, \(K_b\), are equilibrium constants for the dissociation of weak acids and weak bases. 2020 22 Direct link to Diana Dominguez's post It is incorrect because t, Posted 8 years ago. xref This same effect is also used to weaken human hair in preparation for shaving. Answer = if4+ isPolar What is polarand non-polar? All steps. A titration curve displays the multiple acid dissociation constants (\(K_a\)) as portrayed below. in and then for water, we leave water out of our its conjugate base A- has the reaction and equilibrium constant of: \[A^-(aq) + H_2O(l) HA(aq) + OH^-(aq), K'_b=\frac{[HA][OH^-]}{[A^-]}\], \[K_aK'_{b}=\left ( \frac{[H_{3}O^{+}] \textcolor{red}{\cancel{[A^{-}]}}}{ \textcolor{blue}{\cancel{[HA]}}}\right )\left (\frac{ \textcolor{blue}{\cancel{[HA]}}[OH^-]}{ \textcolor{red}{\cancel{[A^-]}}} \right )=[H_{3}O^{+}][OH^-]=K_w=10^{-14}\], So there is an inverse relationship across the conjugate pair. So let me write that here. Direct link to Titi 'Speedy' Oden's post If H2O is present in a gi, Posted 8 years ago. Here is a list of some common polyprotic acids: Polyprotic bases are bases that can attach several protons per molecule. Let me draw these electrons in green and give this a negative charge like that. At first glance this gives an equilibrium constant of, \[K=\frac{[H_{3}O^{+}][A^{-}]}{[HA][H_{2}O]}\]. You'll get a detailed solution from a subject matter expert that helps you learn core concepts. Let's go ahead and draw that in. \[HA^{2}- + H_2O A^{-3} +H_3O^+ \; \; K_{a3}\], Because pKa and pKb values are so small they are often recorded a pX values, where pX= -logX. name. There are two types of weak bases, those as modeled by ammonia and amines, which grab a proton from water, and the conjugate bases of weak acids, which are ions, and grab the proton to form the weak acid. All right, so this value is Acids and Bases: Calculating pH of a Strong Acid, Henderson-Hasselbalch Equation and Example, Acids and Bases: Titration Example Problem, Calculating the Concentration of a Chemical Solution. Chemistry Chapter 14 Study Flashcards | Quizlet It is called slaked lime because it is made by treating lime (CaO) with water. It's a pure liquid. Thewater is omittedfrom the equilibrium constant expression giving. much, much, much greater than one here. So another way to write Answer = C2F2 ( Ethyne ) isNonpolar What is polarand non-polar? On the contrary inorganic bases - like NaOH, KOH, LiOH, Ca(OH)2 - increase pH dissociating. And these electrons in green 1. So H3O plus, the conjugate acid and then A minus would be a base. Hence, it would be a weaker base. You can find out more about our use, change your default settings, and withdraw your consent at any time with effect for the future by visiting Cookies Settings, which can also be found in the footer of the site. This electron pair picks up KA which we call the acid, the acid ionization constant. at donating protons, that means that the chloride Disclaimer - accuracy of the values shown, especially for the strong acids, is questionable. Answer = IF4- isNonpolar What is polarand non-polar? PDF Table of Acids with Ka and pKa Values* CLAS - UC Santa Barbara Preshave products and some shave creams contain potassium hydroxide to force open the hair cuticle and to act as a hygroscopic agent to attract and force water into the hair shaft, causing further damage to the hair. The general equation of a weak base is. Question = Is if4+polar or nonpolar ? Question = Is C2F2polar or nonpolar ? In order to degrade it, supercritical water is used to convert it to the syngas containing carbon monoxide, carbon dioxide, hydrogen and methane. There is virtually no undissociated NaOH left in the solution as it is almost entirely ionized to ions. So either one is fine. Chem Chapter 17 Questions, Concepts, and More Flashcards [24], Potassium hydroxide and its solutions are severe irritants to skin and other tissue.[25]. HSO (aq) + HCN (aq) HSO (aq) + CN (aq) A) HSO, CN B) HSO, HSO C) HSO, CN D) HCN, HSO B) HSO, HSO Consider the reaction below. Solution is formed by mixing known volumes of solutions with known concentrations. noting that the amount ionized is x=[A-], where [A-] is the amount that formed the conjugate base. So we can define the percent ionization of a weak acidas, Let's calculate the % Ionization of 1.0M and 0.01 M Acetic acid (Ka=1.8x10-5). Strong acids are listed at the top left hand corner of the table and have Ka values >1 2. Divide the Kw by the Ka to solve the equation for Kb. However, due to molecular forces, the value of the . You use the formula. For example, production of coke (fuel) from coal often produces much coking wastewater. Table of Solubility Product Constants (K sp at 25 o C). In the case of methanol the potassium methoxide (methylate) forms: (Kb of NH is 1.80 10). If we know K we can determine the pH or hydronium ion concentration using a rice diagram where we start with pure acid and measure determine how much dissociates. For the reactions of dissociation of base: Next dissociation steps are trated the same way. a Bronsted-Lowry base and accepting a proton. BUY Chemistry 10th Edition ISBN: 9781305957404 Author: Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste Publisher: Cengage Learning expand_more Chapter 14 : Acids And Bases expand_more To do that you use. Water is gonna function We're also gonna form a hydronium. then you would get back H2O and HA. Kb of Koh and Kb of Koh - The Perfect Combination If you would like to discover more regarding the island then devote some time reading through the Island Guide section. Based on theKbvalues, NH3 is the strongest base, and it has a smaller pKb value. In this particular case, acetic acid usually acts as the acid (the proton donor) because it is much better acid than water. \[CH_3NH_2(aq) + H_2O(l) CH_3NH_3^+(aq)+OH^- (aq) \\ \\ K=\frac{[CH_3NH_3^+][OH^-]}{[CH_3NH_2]} = 5.0x10^{-4}\], \[A^-(aq) + H_2O(l) HA(aq) + OH^-(aq)\], \[K'_b=\frac{[HA][OH^-]}{[A^-]} \\ \text{ where} \; K_b \; \text{is the basic equilibrium constant of the conjugate base} \; A^- \; \text{of the weak acid HA}\]. When you visit the site, Dotdash Meredith and its partners may store or retrieve information on your browser, mostly in the form of cookies. endstream endobj 2041 0 obj<>/W[1 1 1]/Type/XRef/Index[28 1992]>>stream Thus, SiO2 is attacked by KOH to give soluble potassium silicates. And over here if you think We will now look at weak acids and bases, which do not completely dissociate, and use equilibrium constants to calculate equilibrium concentrations. \[H_2A \rightleftharpoonsH^+ + HA^- \;\;\;\;K_{1}=\frac{[H^+][HA^-]}{[H_2A]} \\ \; \\HA^- \rightleftharpoonsH^+ + A^{-2} \;\;\;\;K_{2}=\frac{[H^+][A^{-2}]}{[HA^-]}\], From section 16.3.5 (Kafor polyprotic acids) and from table 16.3.1 (table of Ka) we see Ka1>>Ka2and we can ignore the effect of the second dissociation on the hyrdonium ion concentration, so if [H2A]initial>100Ka1we can use the weak acid approximation to solve for hydronium. Is going to give us a pKa value of 9.25 when we round. All right, so KA is For the definitions of Kan constants scroll down the page. Some of the examples are methyl amine (CH3NH2), ethyl amine (CH3NH2), hydroxyl amine (HONH2) aniline (C6H5NH2), and pyridine (C5H5N). Please remember that only some of them are included in the trial version database, but you can always enter them manually for calculations. as a Bronsted-Lowry base and a lone pair of Include the problem's values in the . Besides, difference between pKa=-1 and pKa=-10 starts to influence calculation results for the solutions with very high ionic strengths, such calculations are dubious in any case. KOH reacts with carbon dioxide to give potassium bicarbonate: Historically, KOH was made by adding potassium carbonate to a strong solution of calcium hydroxide (slaked lime). The saponification of fats with KOH is used to prepare the corresponding "potassium soaps", which are softer than the more common sodium hydroxide-derived soaps. Therefore, alkali and alkaline earth metal oxides are stronger bases than the corresponding hydroxides.