Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

- search is the most efficient way to navigate the Engineering ToolBox!

Acid and base pH indicators

Colors and pH range for color change of acid base indicators is given together with pKa and structures of the indicators

Sponsored Links

The ranges for the color changes are given in the table below the figure, together with the corresponding pK_a value of the indicators.

The molecule structure of each indicator is shown below the table.

See also pKa values of inorganic acids and bases, organic nitrogen compound and alcohols and carboxylic acids.

acid base pH indicators

Trade name	pH start	pH end	pKa	low pH color	high pH color
Cresol red - step 1	0.2	1.8	1.0	red	yellow
Malachite green -step 1	0.2	1.8	1.3	yellow	green
Thymol blue - step 1	1.2	2.8	1.7	red	yellow
Methyl yellow	2.9	4.0	3.3	red	yellow
Methyl orange	3.1	4.4	3.5	red	yellow
Bromophenol blue	3.0	4.6	4.1	yellow	blue
Congo red	3.0	5.0		blue-violet	red
Methyl orange in xylene cyanol (screened)	3.2	4.2		grey-violet	green
Bromocresol green	3.8	5.4	4.7	yellow	blue
Methyl red	4.4	6.2	5.1	red	yellow
Methyl purple	4.8	5.4		purple	green
Bromocresol purple	5.2	6.8	6.4	yellow	purple
Azolitmin (litmus)	4.5	8.3		red	blue
Bromothymol blue	6.0	7.6	7.3	yellow	blue
Phenol red	6.4	8.0	8.0	yellow	red
Neutral red	6.8	8.0		red	yellow
Cresol red -step 2	7.2	8.8	8.5	yellow	reddish-purple
Naphtholphthalein	7.3	8.7		pale red	greenish-blue
Thymol blue - step 2	8.0	9.6	9.2	yellow	blue
Cresolphthalein	8.2	9.8		colorless	purple
Phenolphthalein	8.3	10.0	9.5	colorless	red-pink
Thymolphthalein	9.0	10.5	9.2	colorless	blue
Alizarin yellow R	10.1	12.0	11.2	yellow	red
Indigo carmine	11.4	13.0		blue	yellow
Malachite green -step 2	11.5	13.2		green	colorless

Structure of ph acid base indicator

Sponsored Links

Related Topics

Material Properties - Material properties for gases, fluids and solids - densities, specific heats, viscosities and more

Related Documents

Acid-base properties of aqueous solutions of salts with ions from both acids and bases - Many salts contains ions that affect the pH in an aqueous solution in both acidic and basic direction
Acids - pH Values - pH of common acids like sulfuric, acetic and more
Alcohols and carboxylic acids - physical data - Molweight, melting and boiling point, density, pKa-values, as well as number of carbon and hydrogen atoms in each molecule are given for 150 different alcohols and acids
Amines, diamines and cyclic organic nitrogen compounds - pKa values - Values for the negative logarithm of the acid dissociation constant, pKa, of the conjugated acid of amines, diamines and cyclic organic nitrogen compounds, shown together with the molecular structure of the acids.
Bases - pH Values - Some common bases as sodium hydroxide, ammonia and more
Buffer solutions - Definitions, explanations and examples of how to make buffer solutions
Food and Foodstuff - pH Values - pH in common food products - like apples, butter, wines and more ..
Inorganic acids and bases - pKa values - Values for the negative logarithm of the acid dissociation constant, pKa, of inorganic acids and bases, as well as hydrated metal ions
pH Definition - Basic (alkaline) vs Acidic - Introduction to pH - acidic and basic (alkaline)
pH in Human Biological Materials - pH in blood, salvia ..
Phenols, alcohols and carboxylic acids - pKa values - For oxygen containing organic compounds this is given: pKa (the negative logarithm of the acid dissociation constant), molecular structures, molar weights, density and melting and boiling points.
Strong and weak acids and bases - The most common strong acids and bases, and some examples of weak acids and bases, together with definition of strong and weak acids and bases
Sulfuric Acid - Density - Density of sulfuric acid at various temperatures and concentrations

Tag Search

en: pH color change acid base pKa structure indicator

Sponsored Links

Engineering ToolBox - SketchUp Extension - Online 3D modeling!

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro .Add the Engineering ToolBox extension to your SketchUp from the SketchUp Pro Sketchup Extension Warehouse!

Translate this page to

About the Engineering ToolBox!

Privacy

We don't collect information from our users. Only emails and answers are saved in our archive. Cookies are only used in the browser to improve user experience.

Some of our calculators and applications let you save application data to your local computer. These applications will - due to browser restrictions - send data between your browser and our server. We don't save this data.

Google use cookies for serving our ads and handling visitor statistics. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected.

AddThis use cookies for handling links to social media. Please read AddThis Privacy for more information.

Advertise in the ToolBox

If you want to promote your products or services in the Engineering ToolBox - please use Google Adwords. You can target the Engineering ToolBox by using AdWords Managed Placements.

Citation

This page can be cited as

Engineering ToolBox, (2017). Acid and base pH indicators. [online] Available at: https://www.engineeringtoolbox.com/pH-color-change-acid-base-pKa-structure-indicator-d_1951.html [Accessed Day Mo. Year].

Modify access date.

close

3D Engineering ToolBox - draw and model technical applications!

2D Engineering ToolBox - create and share online diagram drawing templates!

Engineering ToolBox Apps - mobile online and offline engineering applications!

Scientific Online Calculator

Scientific Calculator

4 15

Sponsored Links