Q: Atomic orbitals are populated with what subatomic particles? Read this paragraph and choose the correct option from the provided answers: A completely bonding molecular orbital contains no nodes (regions of zero electron probability) perpendicular to the internuclear axis, whereas a completelyantibonding molecular orbital contains at least one node perpendicular to the internuclear axis. A sigma () orbital (bonding) or a sigma star (*) orbital(antibonding) is symmetrical about the internuclear axis. Hence all cross-sections perpendicular to that axis are circular. Both a pi () orbital (bonding) and a pi star (*) orbital (antibonding) possess a nodal plane that contains the nuclei, with electron density localized on both sides of the plane. The energies of the molecular orbitals versus those of the parent atomic orbitals can be shown schematically in an energy-level diagram. The electron configuration of a molecule is shown by placing the correct number of electrons in the appropriate energy-level diagram, starting with the lowest-energy orbital and obeying the Pauli principle; that is, placing only two electrons with opposite spin in each orbital. From the completed energy-level diagram, we can calculate thebond order, defined as one-half the net number of bonding electrons. In bond orders, electrons in antibonding molecular orbitals cancel electrons in bonding molecular orbitals, while electrons in nonbonding orbitals have no effect and are not counted. Bond orders of 1, 2, and 3 correspond to single, double, and triple bonds, respectively. Molecules with predicted bond orders of 0 are generally less stable than the isolated atoms and do not normally exist. Molecular orbital energy-level diagrams for diatomic molecules can be created if the electron configuration of the parent atoms is known, following a few simple rules. Most important, the number of molecular orbitals in a molecule is the same as the number of atomic orbitals that interact. The difference between bonding and antibonding molecular orbital combinations is proportional to the overlap of the parent orbitals and decreases as the energy difference between the parent atomic... Choices: - protons - neurons - atoms - electrons A:
electrons
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Q: What helps to convert some molecules to forms that can be taken up by other organisms? Read this paragraph and choose the correct option from the provided answers: Choices: - eukaryotes - protists - scavangers - prokaryotes A:
prokaryotes
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Q: What equals the output power divided by the input power? Read this paragraph and choose the correct option from the provided answers: ; The efficiency equals the output power divided by the input power. Choices: - output - potential - inertia - efficiency A:
efficiency
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Q: What do we call the major artery carrying recently oxygenated blood away from the heart? Read this paragraph and choose the correct option from the provided answers: Arterial Supply The major artery carrying recently oxygenated blood away from the heart is the aorta. The very first branches off the aorta supply the heart with nutrients and oxygen. The next branches give rise to the common carotid arteries, which further branch into the internal carotid arteries. The external carotid arteries supply blood to the tissues on the surface of the cranium. The bases of the common carotids contain stretch receptors that immediately respond to the drop in blood pressure upon standing. The orthostatic reflex is a reaction to this change in body position, so that blood pressure is maintained against the increasing effect of gravity (orthostatic means "standing up"). Heart rate increasesa reflex of the sympathetic division of the autonomic nervous systemand this raises blood pressure. Choices: - capillary - muscular artery - arteriole - aorta A:
aorta
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