Question 1: Which is not a clue that a chemical change has happened?
A. new substance is formed B. temperature change C. size change D. gas is produced
Question 2: Which of the following represents chemical change?
A. wood burning B. ice freezing C. sugar dissolving D. wood being sanded

Question 3: Which of the following food changes represents a physical change?
A. toasting bread B. baking a cake C. making chocolate milk D. cooking an egg
Question 4: Which of the following is an example a chemical change?
A. water evaporating B. melting ice C. food rotting D. boiling water

Salicylic acid is a very important acid. it is used to synthesize the aspirin by treating with acetic anhydride. a 0.2015-g sample of salicylic acid was dissolved in a 100.00-ml volumetric flask, and the solution was diluted to the mark. a 10-ml aliquot of this solution was titrated with standard naoh (0.01130 + 0.2% n) to a phenolphthalein faint pink color end point at 19.81 ml. (a) (calculate the normality of the salicylic acid solution used in the titration. (b) assuming the salicylic acid is pure, what is the equivalent weight of the salicylic acid? practice problems for the final exam (continued) (c) (calculate the inherent error in the determination of the equivalent weight you calculated in part (b). use the following absolute errors in the equipment /glassware when calculating the inherent error. 5.00-ml pipet: + 0.02 ml 100-ml volumetric flask: + 0.08 ml analytical balance: + 0.2 mg 25-ml buret: + 0.03 ml

What is the polyatamic ion of thiosulfate

Find the mass, in grams, of 5.00*10^23 molecules of f2