Dan was studying chemistry for the upcoming test. To understand ionization energy he selected two atoms, atom A and atom B. Atom A was top within a group, but atom B was bottom within a group. He found it easier to understand the concept by comparing these two atoms. Which atom would be smaller in size, atom A or atom B? Hint: 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
Ans: atom A

Two pedologists studied different types of soil. Yun studied forest soils, while Jian studied grassland soil. They were both very surprised with they findings. Which scientist read more about the principal source of soil organic matter in the forest? Hint: In grassland, much of the organic matter added to the soil is from the deep, fibrous, grass root systems. By contrast, tree leaves falling on the forest floor are the principal source of soil organic matter in the forest. Another difference is the frequent occurrence in the grasslands of fires that destroy large amounts of aboveground material but stimulate even greater contributions from roots. Also, the much greater acidity under any forests inhibits the action of certain soil organisms that otherwise would mix much of the surface litter into the mineral soil. As a result, the soils under grasslands generally develop a thicker A horizon with a deeper distribution of organic matter than in comparable soils under forests, which characteristically store most of their organic matter in the forest floor (O horizon) and thin A horizon.
Ans: Yun

Doctors studied two groups of patients. Group W which had people with sickle cell disease, and group A which had normal people in it. Which group had more individuals with genetic abnormalities? Hint: Some individuals have a specific mutation in the primary sequence of their hemoglobin molecules that causes them to aggregate, resulting in a deformation of their red blood cells. This abnormality is genetic in nature. A person may inherit the gene from one parent and have sickle cell trait (only some of the hemoglobin is hemoglobin S), which is usually not life-threatening. Inheriting the gene from both parents will result in sickle cell disease, which is a very serious condition.
Ans: Group W

The 2 team took different approaches in reinforcing the highway embankment slopes when building segments of the interstate. Team A led by Chuck relied almost entirely on inspiration and good building materials, while team B lead by Mike used nature as an ally by planting hundreds of thousand of trees and shrubs to prevent slope failures. Which team contributed to increasing the chances of slope failure? Hint: The major effect of transpiration is the reduction of soil pore water pressures which counteracts the loss of strength which occurs through wetting, this is most readily seen as a loss of moisture around trees. However it is not easy to rely on tree and shrub roots to remove water from slopes and consequently help ensure slope stability. The ability to transpire in wet conditions is severely reduced and therefore any increase in soil strength previously gained in evaporation and transpiration will be lost or significantly reduced, consequently the effects of transpiration cannot be taken into account at these times. However it can be assumed that the chance of slope failure following saturation by storm event or periods of extended rainfall will be lessened as a result of transpiration. Moreover, although changes in moisture content will affect the undrained shear strength, the effective shear stress parameters as commonly used in routine slope stability analysis are not directly influenced by changing moisture content, although the water pressures (suctions) used in the analysis will change.[2][3]
Ans: Team A