Given a scientific passage and an answer, generate a question for the given answer.

Ex Input:
Passage: Biotic factors are all of the living or once-living aspects of the environment. They include all the organisms that live there as well as the remains of dead organisms. Answer: biotic factors

Ex Output:
What are all of the living or once-living aspects of the environment called?

Ex Input:
Passage: 2.2 | Chemical Bonds By the end of this section, you will be able to: Explain the relationship between molecules and compounds Distinguish between ions, cations, and anions Identify the key difference between ionic and covalent bonds Distinguish between nonpolar and polar covalent bonds Explain how water molecules link via hydrogen bonds Atoms separated by a great distance cannot link; rather, they must come close enough for the electrons in their valence shells to interact. But do atoms ever actually touch one another? Most physicists would say no, because the negatively charged electrons in their valence shells repel one another. No force within the human bodyor anywhere in the natural worldis strong enough to overcome this electrical repulsion. So when you read about atoms linking together or colliding, bear in mind that the atoms are not merging in a physical sense. Instead, atoms link by forming a chemical bond. A bond is a weak or strong electrical attraction that holds atoms in the same vicinity. The new grouping is typically more stableless likely to react againthan its component atoms were when they were separate. A more or less stable grouping of two or more atoms held together by chemical bonds is called a molecule. The bonded atoms may be of the same element, as in the case of H2, which is called molecular hydrogen or hydrogen gas. When a molecule is made up of two or more atoms of different elements, it is called a chemical compound. Thus, a unit of water, or H2O, is a compound, as is a single molecule of the gas methane, or CH4. Three types of chemical bonds are important in human physiology, because they hold together substances that are used by the body for critical aspects of homeostasis, signaling, and energy production, to name just a few important processes. These are ionic bonds, covalent bonds, and hydrogen bonds. Answer: bonds

Ex Output:
Ionic, covalent, and hydrogen are three important types of what type of interaction between different types of atoms?

Ex Input:
Passage: A final effect of this trapped radiation merits mention. Alpha decay produces helium nuclei, which form helium atoms when they are stopped and capture electrons. Most of the helium on Earth is obtained from wells and is produced in this manner. Any helium in the atmosphere will escape in geologically short times because of its high thermal velocity. What patterns and insights are gained from an examination of the binding energy of various nuclides? First, we find that BE is approximately proportional to the number of nucleons A in any nucleus. About twice as much energy is needed to pull apart a nucleus like 24 Mg compared with pulling apart 12 C , for example. To help us look at other effects, we divide BE by A and consider the binding energy per nucleon, BE / A . The graph of BE / A in Figure 31.27 reveals some very interesting aspects of nuclei. We see that the binding energy per nucleon averages about 8 MeV, but is lower for both the lightest and heaviest nuclei. This overall trend, in which nuclei with A equal to about 60 have the greatest BE / A and are thus the most tightly bound, is due to the combined characteristics of the attractive nuclear forces and the repulsive Coulomb force. It is especially important to note two thingsthe strong nuclear force is about 100 times stronger than the Coulomb force, and the nuclear forces are shorter in range compared to the Coulomb force. So, for low-mass nuclei, the nuclear attraction dominates and each added nucleon forms bonds with all others, causing progressively heavier nuclei to have progressively greater values of BE / A . This continues up to A 60 , roughly corresponding to the mass number of iron. Beyond that, new nucleons added to a nucleus will be too far from some others to feel their nuclear attraction. Added protons, however, feel the repulsion of all other protons, since the Coulomb force is longer in range. Coulomb repulsion grows for progressively heavier nuclei, but nuclear attraction remains about the same, and so BE / A becomes smaller. This is why stable nuclei heavier than A 40 have more neutrons than protons. Coulomb repulsion is reduced by having more neutrons to keep the protons farther apart (see Figure 31.28). Answer: alpha decay

Ex Output:
What decay produces helium nuclei?