June 2011 Chemistry Regents #80-82

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Questions

Base your answers to questions 80 through 82  on the information below.

Some carbonated beverages are made by forcing carbon dioxide gas into a beverage solution. When a bottle of one kind of carbonated beverage is first opened, the beverage has a pH value of 3.

80. State, in terms of the pH scale, why this beverage is classified as acidic. [1]

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the pH is less than 7, so it is acidic

81. Using Table M, identify one indicator that is yellow in a solution that has the same pH value as this beverage. [1]

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bromthymol blue

bromcresol green

thymol blue

these indicators are yellow for a pH of 3.0

82. After the beverage bottle is left open for several hours, the hydronium ion concentration in the beverage solution decreases to 1/1000 of the original concentration. Determine the new pH of the beverage solution. [1]

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pH=6

1/1000 has 3 zeros pH changes by 3

since hydronium concentration decrease it becomes less acidic (more basic) the pH increases

so a pH of 3 becomes 6

 

on to Questions 83-85

 

Questions 1-10 Questions 11-20 Questions 21-30 Questions 31-40 Questions 41-50

Question 51 Questions 52-54 Questions 55-59 Questions 60-61 Questions 62-63 Questions 64-65 Questions 66-68 Questions 69-70 Questions 71-73 Questions 74-76 Questions 77-79 Questions 80-82 Questions 83-85

 
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