input question: I read this background article the other day: Hydrogen bonds cause water to have a relatively high boiling point of 100C (212F). Because of its high boiling point, most water on Earth is in a liquid state rather than in a gaseous state. Water in its liquid state is needed by all living things. Hydrogen bonds also cause water to expand when it freezes. This, in turn, causes ice to have a lower density (mass/volume) than liquid water. The lower density of ice means that it floats on water. For example, in cold climates, ice floats on top of the water in lakes. This allows lake animals such as fish to survive the winter by staying in the water under the ice. I am facing a new situation today: Scientists are finding more and more evidences of water in the outer space. Earth has mostly liquid water. But that's not the case with other celestial objects. Venus has some water, but it is in gaseous state. On the other hand, water in Jupiter's moon Europa is in frozen state. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: In Europa would the state of water in higher or lower denstiy than in Earth????
output answer: lower

input question: I read this background article the other day: 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. I am facing a new situation today: 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. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which would partially ionize in water, sample A or sample B????
output answer: sample B

input question: I read this background article the other day: Chemical equilibrium was studied by French chemist Henri Le Chatelier (1850-1936), and his description of how a system at equilibrium responds to a change in conditions has become known as Le Chatelier's principle . This principle states that when a chemical system is at equilibrium and is disturbed by a stress, the system will respond by attempting to counteract that stress until a new equilibrium is established. Stresses to a chemical system include changes in the concentrations of reactants or products, changes in the temperature of the system, or changes in the pressure of the system. We will discuss each of these stresses separately. In each case, the change to the equilibrium position will cause either the forward or reverse reaction to be favored over the opposite process. When the forward reaction is favored, the concentrations of the products increase, and the concentrations of the reactants decrease. When the reverse reaction is favored, the concentrations of the products decrease, and the concentrations of the reactants increase. I am facing a new situation today: David was conducting experiments on chemical equilibrium in the chemistry lab. First, he took a chemical system that was at equilibrium. He labeled it as case E. Then he changed the temperature of the system. He labeled that experiment as case T. Finally, he observed two more experiments, case A and case B. In case A forward reaction was favored, and in case B reverse reaction was favored. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Would the reactants concentration increase or decrease in case A than in case B????
output answer: decrease

input question: I read this background article the other day: The ionization energies of the representative elements generally decrease from top to bottom within a group. This trend is explained by the increase in size of the atoms within a group. The valence electron that is being removed is further from the nucleus in the case of a larger atom. The attractive force between the valence electron and the nucleus weakens as the distance between them increases and as the shielding effect increases, resulting in a lower ionization energy for the larger atoms within a group. Although the nucl I am facing a new situation today: Rob is learning about ionization. He looks at a specific group of elements from top to bottom to figure out thier ionization energy. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Given the top element and the bottom element in the group Rob looks at, which has a lower ionization energy????
output answer:
bottom element