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Bases as defined by Arrhenius are Electron pair donors Proton acceptors Substance that produce hydrogen ions in aqueous solution Substance that produce hydroxide ions in aqueous solution All of the above
An example of a strong acid is dilute nitric acid concentrated acetic acid carbonic acid citric acid H2O
A given substance is an acid if inaqueous solution the substance has a pH above 7 has a soapy feeling turns litmus paper red reacts with a metal is colorless
Which of the following statementsis TRUE for all bases? Bases consist of oxides and hydroxides of metals. When bases react with acids, the only product is salt. Bases are colorless. Bases turn phenolphthalein from colorless to pink. Bases taste sour.
The color of phenolphthalein in anacid is colorless.
Indicators used in titration areadded to the titrator the acid only the base only both acid and base the acid or base
A standard solution is one which is basic in nature which is acidic in nature whose concentration is being tested with known concentration which is added to the titrand
When the hydrogen ion (H+) is indicatedin connection with its water solution,the ion represented is OH- H2O+ H2O2+ H3O+ None of the above
Bases as defined by Arrhenius areD. Substance that produce hydroxide ions in aqueous solutionAn Arrhenius base is a substance upon dissociation in water causes an increase in the concentration of the solvent anion, OH+.
An example of a strong acid isA. dilute nitric acidThere are only six strong acids: HCl - hydrochloric acid HNO3 - nitric acid H2SO4 - sulfuric acid HBr - hydrobromic acid HI – hydroiodic acid (also known as hydriodic acid) HClO4 - perchloric acid
A given substance is an acid if inaqueous solution the substanceC. turns litmus paper redAn acid is a substance whose water solution exhibits the following properties: 1. turns litmus paper red 2. has a sour taste 3. neutralizes bases 4. reacts with active metals to produce hydrogen gas
Pure water is neutral.TRUEIn pure water, (H3O+) or more often represented as [H+], is 1.0x10-7 M, and the [OH-] is also 1.0x10-7 M. since [H+] is equal to [OH-], then water is considered neutral.
Which is NOT a base?B. BF3BF3 is a Lewis acid. Mg(OH)2, NH3 and KOH are bases. H2O is amphoteric, it can act as an acid or a base.
Which of the following statements isTRUE for all bases?D. Bases turn phenolphthalein from colorless to pink.Solutions of bases have slippery, soapy feeling and a biting, bitter taste. Like acids, bases also react with indicators. Bases turn red litmus blue, turn methyl orange from red to yellow, and turn phenolphthalein from colorless to pink. Bases neutralize acids to form water and a salt. Bases have hydroxide ion concentration.
The color of phenolphthalein in anacid is colorless.TRUEPhenolphthalein is often used in titrations, it turns colorless in acidic solutions and pink in basic solutions. If the concentration of indicator is particularly strong, it can appear purple.
Indicators used in titration areadded toE. the acid or baseAn indicator is added to the titrand (either an acid or a base), whose concentration is unknown.
A standard solution is oneD. with known concentrationA standard solution is a solution containing a precisely known concentration of an element or a substance. Standard solutions are used to determine the concentrations of other substances, such as solutions in titrations.
NH4+ is a Lewis base.FALSENH4+ is a Lewis acid. It donates one proton (H+). H2O + NH4+ <--> H3O+ + NH3
Calculate the pH of 0.0001 M HClsolution.D. 4Given: [H+] = 0.0001 M [H+] = 10-4Solution: pH = - log [10-4] pH = - (-4) pH = 4
Blood has an acidic pH.FALSEThe pH of blood is 7.35 – 7.45. pH < 7.00 acidic solution pH = 7.00 neutral solution pH > 7.00 basic solutionTherefore, blood has a slightly basic pH.
An acid found in the stomach isC. HCLHydrochloric acid, normally found in the gastric juices, is necessary for the proper digestion of proteins in the stomach.
A pH of 2 is more acidic than a pOHof 12.FALSEpOH is a measure of the concentration of hydroxide ions. pOH = 14 – pH pOH = 14 – 2 pOH = 12Therefore, a pH of 2 is equal to a pOH of 12.
When the hydrogen ion (H+) is indicatedin connection with its watersolution, the ion represented isD. H3O+Hydronium ion (H3O+) is responsible for the observed properties of acids in water. For the sake of simplicity, H+ is often use instead of the more accurate H3O+. For aqueous solutions, whenever H+ is written, it should be understood as H3O+.