Matching -A phosphate buffer solution at pH = pK1 = 2.15 would have equal amounts of phosphate in the ______ form and the H2PO4- form.

A) hydrogen bond B) rotational C) H₃PO₄ D) H₂PO₄– E) HPO₄ 2– F)disordered G)positive entropy H)negative entropy I)higher electronegativity J)insoluble K)tetrahedral arrangement L)acid M)base N)only partially ionized A) hydrogen bond B) rotational C) H₃PO₄ D) H₂PO₄– E) HPO₄ 2– F)disordered G)positive entropy H)negative entropy I)higher electronegativity J)insoluble K)tetrahedral arrangement L)acid M)base N)only partially ionized C

Exam 2: Water | Examlex

Biological processes can be best understood in the context of water. a.What effect does water have on the noncovalent interactions between either charged or polar groups/molecules? b.Why is this effect important with respect to biochemical processes?

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Question 1

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a.Water reduces the strength of those interactions.
b.Water reduces the strength of polar and ionic interactions.This makes those interactions reversible and life is based on reversible interaction between biomolecules.

Phosphoric acid is a polyprotic acid, with pK values of 2.14, 6.86, and 12.38.Which ionic form predominates at pH 9.3?

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Matching -A phosphate buffer solution at pH = pK₁ = 2.15 would have equal amounts of phosphate in the ______ form and the H₂PO₄^- form.

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Rank the following interactions in order of increasing strength (start with the weakest interaction).

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Question 4

You mix equal volumes of 0.05 M NaH₂PO₄ and 0.05 M Na₂HPO₄ (pK's for phosphoric acid are 2.15, 6.82 and 12.38).Which of the following best describes the resulting solution?

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Question 5

Matching -The insolubility of nonpolar molecules in water is due to the large ______, which is the result of water molecules forming an ordered network surrounding nonpolar molecules.

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Question 6

Hydrogen bonds within liquid water

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Question 7

_____ is exceptionally soluble in water due to the formation of hydrogen bonds.

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Question 8

Which of the following statements about water is not true?

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Question 9

A graduate student at SDSU wants to measure the activity of a particular enzyme at pH 4.0.To buffer her reaction, she will use a buffer system based on one of the acids listed below, which acid is most appropriate for the experiment?

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Question 10

Molecules such as methanol and ethanol are very soluble in water because

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Question 11

You mix 999 mL pure water and 1 mL of 2.0 M NaOH.Calculate the pH of the resulting solution.(assume the total volume is 1.0 L).

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Question 12

Globules of up to several thousand amphiphilic molecules arranged with the hydrophilic groups on the surface and the hydrophobic groups buried in the center that form in water are called

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Question 13

Physical properties that depend on the amounts of various species, rather than the identities of those species, are called

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Question 14

Covalent C─C and C─H bonds have bond strengths that are approximately ____ times higher than those of H-bonds.

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Question 15

Methanol can act both as a H-bond donor and as a H-bond acceptor.What is the maximal number of H-bonds a single molecule of methanol can form with surrounding water molecules.

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Question 16

The pH of coffee is 5.6.The pH of grapefruit juice is 2.6.This means that the proton concentration in coffee is

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Question 17

Sheets composed of two layers of amphipathic molecules arranged with the hydrophilic groups on the surface and the hydrophobic groups buried in the center that form in water are called

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Question 18

Matching -A strong acid is completely ionized in water, whereas a weak acid is ______.

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Question 19

The pH of blood is affected by

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Question 20

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Exam 2: Water

Biological processes can be best understood in the context of water. a.What effect does water have on the noncovalent interactions between either charged or polar groups/molecules? b.Why is this effect important with respect to biochemical processes?

Phosphoric acid is a polyprotic acid, with pK values of 2.14, 6.86, and 12.38.Which ionic form predominates at pH 9.3?

Matching -A phosphate buffer solution at pH = pK1 = 2.15 would have equal amounts of phosphate in the ______ form and the H2PO4- form.

Rank the following interactions in order of increasing strength (start with the weakest interaction).

You mix equal volumes of 0.05 M NaH2PO4 and 0.05 M Na2HPO4 (pK's for phosphoric acid are 2.15, 6.82 and 12.38).Which of the following best describes the resulting solution?

Matching -The insolubility of nonpolar molecules in water is due to the large ______, which is the result of water molecules forming an ordered network surrounding nonpolar molecules.

Hydrogen bonds within liquid water

_____ is exceptionally soluble in water due to the formation of hydrogen bonds.

Which of the following statements about water is not true?

A graduate student at SDSU wants to measure the activity of a particular enzyme at pH 4.0.To buffer her reaction, she will use a buffer system based on one of the acids listed below, which acid is most appropriate for the experiment?

Molecules such as methanol and ethanol are very soluble in water because

You mix 999 mL pure water and 1 mL of 2.0 M NaOH.Calculate the pH of the resulting solution.(assume the total volume is 1.0 L).

Globules of up to several thousand amphiphilic molecules arranged with the hydrophilic groups on the surface and the hydrophobic groups buried in the center that form in water are called

Physical properties that depend on the amounts of various species, rather than the identities of those species, are called

Covalent C─C and C─H bonds have bond strengths that are approximately ____ times higher than those of H-bonds.

Methanol can act both as a H-bond donor and as a H-bond acceptor.What is the maximal number of H-bonds a single molecule of methanol can form with surrounding water molecules.

The pH of coffee is 5.6.The pH of grapefruit juice is 2.6.This means that the proton concentration in coffee is

Sheets composed of two layers of amphipathic molecules arranged with the hydrophilic groups on the surface and the hydrophobic groups buried in the center that form in water are called

Matching -A strong acid is completely ionized in water, whereas a weak acid is ______.

The pH of blood is affected by

Introduction to the Chemistry of Life

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Matching -A phosphate buffer solution at pH = pK₁ = 2.15 would have equal amounts of phosphate in the ______ form and the H₂PO₄^- form.

You mix equal volumes of 0.05 M NaH₂PO₄ and 0.05 M Na₂HPO₄ (pK's for phosphoric acid are 2.15, 6.82 and 12.38).Which of the following best describes the resulting solution?