[Q]: Jeremy is studying the periodic table in preparation for a chemistry test next week. Today he is focusing on the elements that all belong to the alkali metals group. He is especially focused on learning about lithium, which is at the top of the group, and cesium, which is at the bottom of the alkali metals group. Which element is smaller? 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
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[A]: lithium

[Q]: Ted had 2 uncles. Uncle Jerry was getting up there in age, he was 78 years-old. Uncle Tom was younger, he was in his early 50's and still very active and productive. Which uncle had more strength and stamina? Hint: Old age begins in the mid-60s and lasts until the end of life. Most people over 65 have retired from work, freeing up their time for hobbies, grandchildren, and other interests. Stamina, strength, reflex time, and the senses all decline during old age, and the number of brain cells decreases as well. The immune system becomes less efficient, increasing the risk of serious illnesses such as cancer and pneumonia. Diseases such as Alzheimer's disease that cause loss of mental function also become more common.
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[A]: Tom

[Q]: Two rivers spring from the same mountain. Olt was a fast moving river, while Mures river was slow moving and deep. Both rivers are very important for the local economies. Which river didn't have a food source mostly derived from algae? Hint: The major zones in river ecosystems are determined by the river bed's gradient or by the velocity of the current. Faster moving turbulent water typically contains greater concentrations of dissolved oxygen, which supports greater biodiversity than the slow moving water of pools. These distinctions form the basis for the division of rivers into upland and lowland rivers. The food base of streams within riparian forests is mostly derived from the trees, but wider streams and those that lack a canopy derive the majority of their food base from algae. Anadromous fish are also an important source of nutrients. Environmental threats to rivers include loss of water, dams, chemical pollution and introduced species. A dam produces negative effects that continue down the watershed. The most important negative effects are the reduction of spring flooding, which damages wetlands, and the retention of sediment, which leads to loss of deltaic wetlands.
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[A]: Olt

[Q]: Jake and his brother Jordan both have to go to the dentist to get a tooth pulled. Jake is allergic to the anesthetic unfortunately, so he has to have the procedure done without it. Jordan isn't allergic, so he is able to get his tooth pulled after an anesthetic is injected. Who will experience less pain during the tooth extraction? Hint: When you go to the dentist to get a tooth pulled, you really don't want to feel any pain. The dentist injects an anesthetic into your gum and it eventually becomes numb. One theory as to why anesthetics work deals with the movement of ions across the cell membrane. The anesthetic gets into the membrane structure and causes shifts in how ions move across the membrane. If ion movement is disrupted, nerve impulses will not be transmitted and you will not sense pain at least not until the anesthetic wears off.
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[A]:
Jordan