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The student then followed the reaction with a spectrophotometer, which records the light absorbed by the mixture and so gives the concentration of the dye throughout the reaction. The graph shows [D+] against time for experiment 3. (i) Use the graph to…
Explain, in terms of collision theory, why raising the temperature of the reaction mixture from 20 °C to 30 °C increases the rate of the reaction between D+ and OH−.
The amino acids glycine and alanine react together to form a dipeptide. Identify the type of bond that joins the two amino acid residues in the dipeptide.
Equal amounts of each of the following oxides are added to separate samples of water of the same volume. Which oxide gives the solution with the lowest pH? A. CO B. SO3 C. K2O D. CO2
Complete the diagram of a standard hydrogen electrode by writing in each box the feature that it points to.
A standard hydrogen electrode is connected to a half-cell consisting of a zinc rod in a solution of zinc nitrate, Zn(NO3)2(aq), to form a voltaic cell. (i) Write the cell diagram for the spontaneous reaction, using "|" for a phase boundary and "||" for…
The structural formula of a synthetic tripeptide P is shown. Circle every amide link in the structure.
Which set of ions shows increasing ionic radii? A. Mg2+ < Na+ < O2− < F− B. Mg2+ < Na+ < F− < O2− C. O2− < F− < Na+ < Mg2+ D. Na+ < Mg2+ < F− < O2−
Potassium iodide, KI, and potassium metal, K, are both solids at room temperature. State the type of bonding in each of the two solids and describe it.
Molten potassium iodide is electrolysed. Write the half-equation for the reaction at each electrode: the positive electrode (anode) and the negative electrode (cathode).