Select all the correct answers. Which sentences describe chemical changes?
The temperature of water rises when heated.
When mixed, water and limestone give off heat.
A mixture of red paint and green paint becomes black.
On adding yellow turmeric to a transparent soap solution, the mixture turns bright red.
When ground into powder, grains of wheat become flour.
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Achemistry student needs to standardize a fresh solution of sodium hydroxide. he carefully weighs out of oxalic acid , a diprotic acid that can be purchased inexpensively in high purity, and dissolves it in of distilled water. the student then titrates the oxalic acid solution with his sodium hydroxide solution. when the titration reaches the equivalence point, the student finds he has used of sodium hydroxide solution. calculate the molarity of the student's sodium hydroxide solution. be sure your answer has the correct number of significant digits.