what colours do alkalis turn universal indicator
http://en.wikipedia.org/wiki/Universal_indicator
Alkalis are known to turn universal indicator into specific colors to indicate their pH level. Universal indicator is a mixture of several different indicators, which are substances that change color depending on the pH of a solution. To determine the colors that alkalis turn universal indicator, you can follow these steps:
1. Start by preparing a solution of the alkali you want to test. You can dissolve a small amount of the alkali substance (such as sodium hydroxide or potassium hydroxide) in water to create the solution.
2. Obtain a small sample of universal indicator. Universal indicator is usually in the form of paper strips or a liquid solution. Make sure the universal indicator is colorless before starting the test.
3. Dip the universal indicator paper strip into the alkali solution or add a few drops of the alkali solution to the universal indicator liquid.
4. Observe the color change of the universal indicator. Depending on the strength of the alkali solution, it will cause the universal indicator to change to a specific color or a range of colors.
In general, alkalis turn universal indicator into shades of blue, purple, or dark green. The specific color can vary depending on the concentration of the alkali. For example, a strong alkali will typically turn the indicator to a dark blue or purple color, while a weaker alkali may result in a lighter blue or green color.
Remember, when dealing with chemicals, it is important to handle them safely and follow any relevant safety precautions.