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Which feature of the hydrogen emission spectrum shows that the spacing between the electron energy levels decreases as the energy of the levels increases? A. The lines within each series get closer together towards the high-frequency end B. The spectrum…
(i) Suggest one hazard to health or safety in Student A's procedure. (ii) Student A plotted the highest temperature of each mixture against the volume of nitric acid. With a ruler, draw two straight lines of best fit: one following the rising set of points and…
Student B pipetted 30.00 cm3 of the potassium hydroxide solution into a 150 cm3 glass beaker and added the nitric acid from a burette in portions of 4.00 cm3, recording the steady temperature after each addition. (i) From a…
(i) In aqueous solution sulfuric acid transfers a proton to a water molecule, forming the hydroxonium ion, H3O+. Annotate the structure of the hydroxonium ion to indicate the coordination bond. (ii) Write an equation for the reaction between excess…
(i) For the carbonate ion, draw its Lewis formula. (ii) Write the chemical formula of ammonium carbonate.
The diagrams show the 3s and 3p sublevels of a sulfur atom; the inner sublevels are full. Which diagram represents the ground-state electron configuration, in agreement with the Pauli exclusion principle and Hund's rule? A. Diagram A B. Diagram B C. Diagram C…
Each beaker used as a chromatography chamber was covered with a watch glass while the solvent rose up the paper. Explain why the chamber has to be covered for the experiment to be properly designed.
Explain why the start line must be horizontal and must be above the level of the solvent when the strip is placed in the chamber.
For the orange dye, calculate the retardation factor, RF, obtained in each solvent system.
Deduce, giving a reason, which of the two dyes, orange or violet, is the more polar.