A paracetamol tablet was crushed and an excess of HCl 25cm³ of 1.0mol was added. the result of the solution was titrate against 0.5mol of NaOH. calculate the mass of CaCO3 in the paracetamol.

The bohr model of the atom explained why emission spectra are discrete. it could also be used to explain the photoelectric effect. which is a correct explanation of the photoelectric effect according to the model?

Which of the following characteristics are true of enzymes? check all that apply. a.)the structure of an enzyme can change if conditions change. b.)a single enzyme can normally catalyze a wide variety of reactions under many conditions. c.)enzymes are found only in nonliving systems. d.)enzymes allow living things to regulate body conditions through feedback mechanisms. e.)enzymes bind to specific substrates in specific ways. f.)enzymes increase the rate of reaction. g.)when shown in energy-reaction diagrams, enzymes represent the higher activation energy.

For part 1, describe the changes in the colors of the well, if any, as you go from well 1 to well 9—that is, as you go from the well with the least copper(ii) nitrate to the well with the most copper(ii) nitrate. which wells had the most distinct precipitate? for part 2, describe the changes in the colors of the well, if any, as you go from well 1 to well 9—that is, as you go from the well with the least iron(ii) sulfate to the well with the most iron(ii) sulfate. which wells had the most distinct precipitate? for part 3, describe the changes in the colors of the well, if any, as you go from well 1 to well 9—that is, as you go from the well with the least iron(iii) nitrate to the well with the most iron(iii) nitrate. which wells had the most distinct precipitate?