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The iodine number of a fat or oil is the mass, in grams, of iodine that reacts with 100 g of the fat or oil. It is a measure of the degree of unsaturation. A 3.50 g sample of peanut oil reacts completely with 65.5 cm3 of…
An electron in a hydrogen atom falls from the energy level n = 4 to the energy level n = 2. Which statement is correct? A. A photon is emitted and its energy equals the difference between the two energy levels B. A photon is absorbed and its energy equals…
Molten potassium iodide is electrolysed. Write the half-equation for the reaction at each electrode: the positive electrode (anode) and the negative electrode (cathode).
Potassium permanganate reacts with potassium iodide in alkaline solution. 6 MnO4−(aq) + I−(aq) + 6 OH−(aq) → 6 MnO42−(aq) + IO3−(aq) + 3 H2O(l) Identify the species oxidized and the number of electrons transferred in the equation as written.
Pantothenic acid (vitamin B5) is added to some processed foods. Its structure is shown. Predict, giving one reason, whether pantothenic acid is soluble in vegetable oil.
Which element is in the f-block of the periodic table? A. U B. Ba C. Hf D. Rf
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−
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
When the same amount of each oxide is added to an equal volume of water, which oxide produces the solution with the lowest pH? A. Li2O B. Al2O3 C. SO3 D. CO2