A container with small books of blue litmus test papers (with one open book) as used in a UK secondary/high school.

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Size: 3171px × 4756px
Location: London, UK
Photo credit: © Maurice Savage / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: blue, book, books, british, education, educational, england, high, indicator, johnson, litmus, open, pads, paper, papers, school, science, secondary, small, table, test, uk