Chemistry
Solutions and pH Chemistry
451 Questions
Solutions and pH chemistry focus on the acidity or alkalinity of various substances, from human urine to acidic soils. Questions involve titration calculations, molarity determination, and understanding mole fractions. This topic is a staple in the chemistry sections of state and national level competitive exams.
Calculating solution molarityMole fraction calculationpH value interpretationAcidic soils and pHTitration and neutralization
Solutions and pH Chemistry Questions
B
Correct answer
Explanation
The pH scale ranges from 0 to 14. Solutions with a pH greater than 7 are basic, while those with a pH less than 7 are acidic.
A
Correct answer
Explanation
The pH scale measures acidity and alkalinity. A pH value less than 7 indicates an acidic solution.
A
Correct answer
Explanation
Alkalis have pH above 7 because the pH scale measures acidity/alkalinity, with 7 being neutral. Alkalis are basic substances with pH values greater than 7 (typically 8-14 for common alkalis). Acids have pH below 7, while pH 7 itself is neutral (neither acidic nor alkaline).
B
Correct answer
Explanation
Normal rain is slightly acidic (around 5.6), but acid rain is defined by a significantly lower pH, typically ranging from 1 to 4 due to pollutants like sulfur dioxide and nitrogen oxides.
A
Correct answer
Explanation
In any aqueous solution, the product of hydronium and hydroxide ion concentrations is constant. If pH > 7, the solution is basic, meaning hydroxide ions outnumber hydronium ions.
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acidic
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basic
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neutral
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salts
B
Correct answer
Explanation
The pH scale ranges from 0 to 14. Values above 7 indicate a basic solution, while values below 7 indicate an acidic solution.
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acidic
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basic
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alkaline
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neutral
A
Correct answer
Explanation
The pH scale measures acidity and alkalinity. Values below 7 are acidic, and values above 7 are basic or alkaline.
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the pH of 9 has more hydronium ions than the pH of 8
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the pH of 9 has less hydronium ions than the pH of 8
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the pH of 8 has more hydronium ions than the pH of 9
B
Correct answer
Explanation
The pH scale is logarithmic; a lower pH indicates a higher concentration of hydronium ions. Therefore, a pH of 8 has 10 times more hydronium ions than a pH of 9.
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the number of moles of a solute present in one litre of the solution.
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the number of moles of a solute present in 1000 gm of the solvent
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the number of gram equivalent of solute present in one litre of solution.
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the ratio of the number of moles of solute to the total number of moles o
A
Correct answer
Explanation
Molarity is defined as the number of moles of solute per liter of solution.
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slightly acidic
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slightly basic
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exactly neutral
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strongly basic
A
Correct answer
Explanation
Normal precipitation has a pH of approximately 5.6 because atmospheric carbon dioxide dissolves in rainwater to form weak carbonic acid, making it naturally slightly acidic.
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6.5-7.5
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2.0-3.5
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3.5-5.0
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9.0-10.5
A
Correct answer
Explanation
Most freshwater plants and animals thrive in a near-neutral pH range, typically between 6.5 and 7.5. Values significantly lower or higher can be harmful to aquatic life.
A
Correct answer
Explanation
The pH scale ranges from 0 to 14. Acids have a pH less than 7, while bases have a pH greater than 7.
B
Correct answer
Explanation
Saliva is generally neutral, with a pH typically ranging between 6.2 and 7.6, making 7 the best approximation.
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20 gtts/min
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17 ml/hr
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20 ml/hr
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17 gtts/min
D
Correct answer
Explanation
The formula is (Volume in ml * Drop factor) / Time in minutes. Here, (50 ml * 20 gtts/ml) / 60 minutes = 1000 / 60 = 16.66, which rounds to 17 gtts/min.
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0.166666 ml/hr
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0.1 ml/hr
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166.67 ml/hr
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168 ml/hr
C
Correct answer
Explanation
The concentration is 30,000 units / 1000 ml = 30 units/ml. To deliver 5,000 units/hr, divide the desired dose by the concentration: 5000 / 30 = 166.67 ml/hr.