{"id":885,"date":"2018-03-20T16:28:36","date_gmt":"2018-03-20T16:28:36","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/suny-orgbiochemistry\/?post_type=chapter&p=885"},"modified":"2018-10-03T14:27:11","modified_gmt":"2018-10-03T14:27:11","slug":"10-6-end-of-chapter-material","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/suny-monroecc-orgbiochemistry\/chapter\/10-6-end-of-chapter-material\/","title":{"raw":"10.6 End-of-Chapter Material","rendered":"10.6 End-of-Chapter Material"},"content":{"raw":"
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Chapter Summary<\/h3>\r\n

To ensure that you understand the material in this chapter, you should review the meanings of the bold terms in the following summary and ask yourself how they relate to the topics in the chapter.<\/em><\/p>\r\n

The earliest chemical definition of an acid, the Arrhenius definition<\/strong>, says that an acid<\/strong> is a compound that increases the amount of hydrogen ion (H+<\/sup>) in aqueous solution. An Arrhenius base<\/strong> is a compound that increases the amount of hydroxide ion (OH\u2212<\/sup>) in aqueous solution. While most bases are named as ionic hydroxide compounds, aqueous acids have a naming system unique to acids. Acids and bases react together in a characteristic chemical reaction called neutralization<\/strong>, in which the products are water and a salt. The principles of stoichiometry, along with the balanced chemical equation for a reaction between an acid and a base, can be used to determine how much of one compound will react with a given amount of the other.<\/p>\r\n

A Br\u00f8nsted-Lowry acid<\/strong> is any substance that donates a proton to another substance. A Br\u00f8nsted-Lowry base<\/strong> is any substance that accepts a proton from another substance. The reaction of ammonia with water to make ammonium ions and hydroxide ions can be used to illustrate Br\u00f8nsted-Lowry acid and base behavior.<\/p>\r\n

Some compounds can either donate or accept protons, depending on the circumstances. Such compounds are called amphiprotic<\/strong>. Water is one example of an amphiprotic compound. One result of water being amphiprotic is that a water molecule can donate a proton to another water molecule to make a hydronium ion and a hydroxide ion. This process is called the autoionization of water<\/strong> and occurs in any sample of water.<\/p>\r\n

Not all acids and bases are equal in chemical strength. A strong acid<\/strong> is an acid whose molecules are all dissociated into ions in aqueous solution. Hydrochloric acid is an example of a strong acid. Similarly, a strong base<\/strong> is a base whose molecules are dissociated into ions in aqueous solution. Sodium hydroxide is an example of a strong base. Any acid or base whose molecules are not all dissociated into ions in aqueous solution is a weak acid<\/strong> or a weak base<\/strong>. Solutions of weak acids and weak bases reach a chemical equilibrium<\/strong> between the un-ionized form of the compound and the dissociated ions. It is a dynamic equilibrium because acid and base molecules are constantly dissociating into ions and reassociating into neutral molecules.<\/p>\r\n

The pH<\/strong> scale is a scale used to express the concentration of hydrogen ions in solution. A neutral solution, neither acidic nor basic, has a pH of 7. Acidic solutions have a pH lower than 7, while basic solutions have a pH higher than 7.<\/p>\r\n

Buffers<\/strong> are solutions that resist dramatic changes in pH when an acid or a base is added to them. They contain a weak acid and a salt of that weak acid, or a weak base and a salt of that weak base. When a buffer is present, any strong acid reacts with the anion of the salt, forming a weak acid and minimizing the presence of hydrogen ions in solution. Any strong base reacts with the weak acid, minimizing the amount of additional hydroxide ions in solution. However, buffers only have limited capacity<\/strong>; there is a limit to the amount of strong acid or strong base any given amount of buffer will react with.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n

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Additional Exercises<\/h3>\r\n<\/div>\r\n
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    A friend brings you a small sample of an unknown chemical. Assuming that the chemical is soluble in water, how would you determine if the chemical is an acid or a base?<\/p>\r\n\r\n<\/div><\/li>\r\n \t

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    A neutral solution has a hydrogen ion concentration of about 1 \u00d7 10\u22127<\/sup> M. What is the concentration of the hydroxide ion in a neutral solution?<\/p>\r\n\r\n<\/div><\/li>\r\n<\/ol>\r\n<\/div>\r\n

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    Answers<\/h3>\r\n[reveal-answer q=\"207799\"]Show Answer[\/reveal-answer]\r\n[hidden-answer a=\"207799\"]\r\n\r\n1. One way is to add it to NaHCO3<\/sub>; if it bubbles, it is an acid. Alternatively, add the sample to litmus and look for a characteristic color change (red for acid, blue for base).\r\n\r\n2.\u00a0A neutral solution has equal concentrations of hydronium and hydroxide ions, so the hydroxide ion concentration is also 1 \u00d7 10\u22127<\/sup> M.\r\n\r\n[\/hidden-answer]\r\n
    <\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>","rendered":"
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    Chapter Summary<\/h3>\n

    To ensure that you understand the material in this chapter, you should review the meanings of the bold terms in the following summary and ask yourself how they relate to the topics in the chapter.<\/em><\/p>\n

    The earliest chemical definition of an acid, the Arrhenius definition<\/strong>, says that an acid<\/strong> is a compound that increases the amount of hydrogen ion (H+<\/sup>) in aqueous solution. An Arrhenius base<\/strong> is a compound that increases the amount of hydroxide ion (OH\u2212<\/sup>) in aqueous solution. While most bases are named as ionic hydroxide compounds, aqueous acids have a naming system unique to acids. Acids and bases react together in a characteristic chemical reaction called neutralization<\/strong>, in which the products are water and a salt. The principles of stoichiometry, along with the balanced chemical equation for a reaction between an acid and a base, can be used to determine how much of one compound will react with a given amount of the other.<\/p>\n

    A Br\u00f8nsted-Lowry acid<\/strong> is any substance that donates a proton to another substance. A Br\u00f8nsted-Lowry base<\/strong> is any substance that accepts a proton from another substance. The reaction of ammonia with water to make ammonium ions and hydroxide ions can be used to illustrate Br\u00f8nsted-Lowry acid and base behavior.<\/p>\n

    Some compounds can either donate or accept protons, depending on the circumstances. Such compounds are called amphiprotic<\/strong>. Water is one example of an amphiprotic compound. One result of water being amphiprotic is that a water molecule can donate a proton to another water molecule to make a hydronium ion and a hydroxide ion. This process is called the autoionization of water<\/strong> and occurs in any sample of water.<\/p>\n

    Not all acids and bases are equal in chemical strength. A strong acid<\/strong> is an acid whose molecules are all dissociated into ions in aqueous solution. Hydrochloric acid is an example of a strong acid. Similarly, a strong base<\/strong> is a base whose molecules are dissociated into ions in aqueous solution. Sodium hydroxide is an example of a strong base. Any acid or base whose molecules are not all dissociated into ions in aqueous solution is a weak acid<\/strong> or a weak base<\/strong>. Solutions of weak acids and weak bases reach a chemical equilibrium<\/strong> between the un-ionized form of the compound and the dissociated ions. It is a dynamic equilibrium because acid and base molecules are constantly dissociating into ions and reassociating into neutral molecules.<\/p>\n

    The pH<\/strong> scale is a scale used to express the concentration of hydrogen ions in solution. A neutral solution, neither acidic nor basic, has a pH of 7. Acidic solutions have a pH lower than 7, while basic solutions have a pH higher than 7.<\/p>\n

    Buffers<\/strong> are solutions that resist dramatic changes in pH when an acid or a base is added to them. They contain a weak acid and a salt of that weak acid, or a weak base and a salt of that weak base. When a buffer is present, any strong acid reacts with the anion of the salt, forming a weak acid and minimizing the presence of hydrogen ions in solution. Any strong base reacts with the weak acid, minimizing the amount of additional hydroxide ions in solution. However, buffers only have limited capacity<\/strong>; there is a limit to the amount of strong acid or strong base any given amount of buffer will react with.<\/p>\n<\/div>\n<\/div>\n

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    Additional Exercises<\/h3>\n<\/div>\n
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      A friend brings you a small sample of an unknown chemical. Assuming that the chemical is soluble in water, how would you determine if the chemical is an acid or a base?<\/p>\n<\/div>\n<\/li>\n

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      A neutral solution has a hydrogen ion concentration of about 1 \u00d7 10\u22127<\/sup> M. What is the concentration of the hydroxide ion in a neutral solution?<\/p>\n<\/div>\n<\/li>\n<\/ol>\n<\/div>\n

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      Answers<\/h3>\n
      Show Answer<\/span><\/p>\n
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      1. One way is to add it to NaHCO3<\/sub>; if it bubbles, it is an acid. Alternatively, add the sample to litmus and look for a characteristic color change (red for acid, blue for base).<\/p>\n

      2.\u00a0A neutral solution has equal concentrations of hydronium and hydroxide ions, so the hydroxide ion concentration is also 1 \u00d7 10\u22127<\/sup> M.<\/p>\n<\/div>\n<\/div>\n

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      Candela Citations<\/h3>\n\t\t\t\t\t
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      CC licensed content, Shared previously<\/div>