pH Scale and Indicators Explained
The pH scale measures the acidity or alkalinity of a solution using the concentration of hydrogen ions (H+). pH indicators are substances that change color
TL;DR: The pH scale measures the acidity or alkalinity of a solution using the concentration of hydrogen ions (H+). pH indicators are substances that change…
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pH Scale and Indicators: The pH scale measures the acidity or alkalinity of a solution using the concentration of hydrogen ions (H+). pH indicators are substances that change color
pH Scale and Indicators Explained Simply
The pH scale measures the acidity or alkalinity of a solution using the concentration of hydrogen ions (H+). pH indicators are substances that change color This is a key Chemistry concept for 10.
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Frequently Asked Questions
Why is milk slightly acidic if no acid is added to it?
Milk contains lactic acid naturally, produced by bacteria during storage. Fresh milk is slightly acidic (pH ~6.6) due to dissolved CO2 and other weak acids, not from added acids.
Can pH be negative or greater than 14?
Yes, pH can be negative for very strong acid solutions with [H+] > 1 mol/L. Similarly, pH can exceed 14 for very strong base solutions. However, the simple pH scale (0-14) applies to dilute solutions at 25°C.
Why do we add indicators to acid-base titrations instead of using pH paper?
pH indicators show a sharp, distinct color change at the equivalence point, making it easy to detect when titration is complete. pH paper gives approximate values and is not precise enough for quantitative analysis.