[Q]: Please answer correctly the following question related to the paragraph below. Which would fully ionize in water, sample A or sample B? David is a chemical engineer. Yesterday, he was working on two samples, sample A and sample B. Sample A was a strong acid, and sample B was a weak acid. David needed to find the differences between them. Hint: The strength of an acid refers to its ability or tendency to lose a proton. A strong acid is one that completely dissociates in water; in other words, one mole of a strong acid HA dissolves in water yielding one mole of H+ and one mole of the conjugate base, A, and none of the protonated acid HA. In contrast, a weak acid only partially dissociates and at equilibrium both the acid and the conjugate base are in solution. Examples of strong acids are hydrochloric acid (HCl), hydroiodic acid (HI), hydrobromic acid (HBr), perchloric acid (HClO4), nitric acid (HNO3) and sulfuric acid (H2SO4). In water each of these essentially ionizes 100%. The stronger an acid is, the more easily it loses a proton, H+. Two key factors that contribute to the ease of deprotonation are the polarity of the HA bond and the size of atom A, which determines the strength of the HA bond. Acid strengths are also often discussed in terms of the stability of the conjugate base.
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[A]: sample A

[Q]: Please answer correctly the following question related to the paragraph below. Where people are in acute need of added iodide, coastal area or inland? People in the coastal area naturally get more iodide from food items because the soil has more iodized salt. But farther we go inland, the soil lacks necessary iodine. As a result, inland population do not get enough iodine naturally. Hint: Before iodized salt was developed, some people experienced a number of developmental difficulties, including problems with thyroid gland function and mental retardation. In the 1920s, we learned that these conditions could usually be treated easily with the addition of iodide anion to the diet. One easy way to increase iodide intake was to add the anion to table salt. This simple step greatly enhanced health and development. Large amounts of iodide ion are also found in seaweed such as kelp (see picture above) and saltwater fish.
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[A]: inland

[Q]: Please answer correctly the following question related to the paragraph below. Which city would have more rocks that had experienced chemical reactions over the previous weeks? A geologist is examining rocks found in neighboring cities. City A recently experienced heavy rainfall for several weeks. Meanwhile, city B hasn't had a single rainy day in the same time span. Hint: Rainfall in an area is important because it influences the rate of weathering. More rain means that more rainwater passes through the soil. The rainwater reacts chemically with the particles. The top layers of soil are in contact with the freshest water, so reactions are greatest there. High rainfall increases the amount of rock that experiences chemical reactions. High rainfall may also carry material away. This means that new surfaces are exposed. This increases the rate of weathering.
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[A]: City A

[Q]: Please answer correctly the following question related to the paragraph below. Who is exposed to sound waves with greater intensity? Jeremy works on a construction site operating a jackhammer and a large welding machine. Jeremy is frequently exposed to sounds with high decibel levels due to being around these machines so often. Jeremy's brother, Alexander, on the other hand works in a library. Unlike Jeremy, Alexander is frequently exposed to sounds with very low decibel levels during his work. Hint: The Figure below shows decibel levels of several different sounds. As decibel levels get higher, sound waves have greater intensity and sounds are louder. For every 10-decibel increase in the intensity of sound, loudness is 10 times greater. Therefore, a 30-decibel "quiet" room is 10 times louder than a 20-decibel whisper, and a 40-decibel light rainfall is 100 times louder than the whisper. High-decibel sounds are dangerous. They can damage the ears and cause loss of hearing.
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[A]:
Jeremy