The indicator of acidity of the environment – a pH value of Ph serves as quantity characteristic of acidity of solutions. It shows a measure of activity of ions of hydrogen and is calculated as a negative decimal logarithm. Solutions with Ph indicator less than 7 are sour, with an indicator more than 7 – alkaline. If the pH value equals the 7th, then Wednesday is neutral.
It is required to you
- For determination of acidity of the environment we will use acid-base indicators. Most just in use litmus, phenolphthalein and methyl orange are also most often applicable. Acidities of the environment is defined visually, depending on color of the indicator in the studied solution.
Instruction
1. Let's add a littlethawphenolphthalein to solution. If liquid remained transparent, so acidic environment. Changed color to violet – Wednesday alkaline.
2. If at addition in solution of several drops of methyl orange, the studied liquid becomes red – acidic environment. When coloring in yellow color, we understand that Wednesday alkaline. The liquid after coloring is lighter, the Ph-indicator is more.
3. Take a litmus piece of paper and moisten its tip in the studied solution. If paper reddened, then acidic environment. Became violet – alkaline.