Blue and red litmus paper and phenophthalein strips are mixed-indicator tests designed for fast, accurate, and reliable pH solution testing.
• Instant pH readings
• Accurate for a wide range of routine pH testing
• Convenient and portable for field use
• Choice of blue and red litmus paper or phenophthalein strips
• Color change in pH solutions ranging from approximately 5 to 8
Whatman™’s acid-alkali litmus paper is impregnated with a mixture of pH indicators. They assume a color specific to sample pH upon contact with a sample.
• Red litmus paper turns blue in alkaline solutions
• Blue litmus paper turns red in acidic solutions
• Phenophthalein strips are colorless in acidic solutions and pink in basic solutions
The convenience of using indicator papers for the rapid determination of pH values has a variety of applications in laboratories and industry.
Blue and red litmus papers
These easy-to-use test papers facilitate a general test for acid or alkaline reactions. Change in color occurs around pH 5 to 8. Blue and red litmus paper reels are particularly recommended for educational use.
Phenophthalein white paper changes to pink at pH 8.3 and becomes red at pH 10. These pH indicator strips are useful for the determination of the neutralization point in weak acid/strong alkali reactions.