A Solution of HF Is Titrated with a 0

question 50

Multiple Choice

A solution of HF is titrated with a 0.150 M NaOH solution. Based on the table above, the best indicator for this reaction is . The K_a of hydrofluoric acid is 6.8 × 10^{- 4}.

• A) methyl orange
• B) phenolpthalein
• C) methyl red
• D) thymol blue
• E) bromocresol purple

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Definitions:

Pyroclastic Flow

A fast-moving current of hot gas and volcanic materials (such as ash and rock fragments) that flows down the side of a volcano during an explosive eruption.

Mudflows

Fast-moving rivers of mud, usually triggered by heavy rainfall or volcanic activity, capable of causing significant damage.

Landslides

The rapid movement of a large amount of earth material, such as rock or soil, down a slope, often triggered by rain or earthquakes.

Mudflows

Rapidly flowing mixtures of water and sediment, usually occurring in areas with steep terrain and loose soil, often initiated by intense rainfall or volcanic activity.