Phenolphthalein turn pink in basic solutions.it turn colourless in acid solution.
Hence options(1)is correct
I believe the correct answer from the choices listed above is the second option. The pair of elements that is most likely to chemically combine and form ionic bonds would be <span>lithium and chlorine. Lithium is metal and chlorine is nonmetal which as a compound forms ionic bonds. Hope this answers the question.</span>
According to table N, the isotopes uranium-238 and uranium-235 have different half lives.
<h3>What are radioactive nuclides?</h3>
Radioactive nuclides are those nuclides that are able to undergo radioactive decay. They have specific modes of decay that is peculiar to each isotope.
Hence, according to table N, the isotopes uranium-238 and uranium-235 have different half lives.
Learn more about uranium-238:brainly.com/question/9099776
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