Q: Q: In many cases, the alkali metal amide salt (mnh2) is not very soluble in liquid ammonia and does what? Read this paragraph and choose the correct option from the provided answers: where the (am) designation refers to an ammonia solution, analogous to (aq) used to indicate aqueous solutions. Without a catalyst, the reaction in Equation 21.20 tends to be rather slow. In many cases, the alkali metal amide salt (MNH2) is not very soluble in liquid ammonia and precipitates, but when dissolved, very concentrated solutions of the alkali metal are produced. One mole of Cs metal, for example, will dissolve in as little as 53 mL (40 g) of liquid ammonia. The pure metal is easily recovered when the ammonia evaporates. Solutions of alkali metals in liquid ammonia are intensely colored and good conductors of electricity due to the presence of solvated electrons (e, NH3), which are not attached to single atoms. A solvated electron is loosely associated with a cavity in the ammonia solvent that is stabilized by hydrogen bonds. Alkali metalliquid ammonia solutions of about 3 M or less are deep blue (Figure 21.11 "Alkali MetalLiquid Ammonia Solutions") and conduct electricity about 10 times better than an aqueous NaCl solution because of the high mobility of the solvated electrons. As the concentration of the metal increases above 3 M, the color changes to metallic bronze or gold, and the conductivity increases to a value comparable with that of the pure liquid metals. Choices: - settles - isolates - evaporates - precipitates A:
A: precipitates

Q: Q: We divide up the earth's seas into five what, which are really all interconnected? Read this paragraph and choose the correct option from the provided answers: People divide up the seas into five oceans. But they are really all interconnected. Even so, they are all very different. This ocean is near a shore and is obviously in a cold region. It appears to be a good habitat for whales! No matter what, the oceans have a huge influence on the planet, locally and as a whole. Choices: - lakes - continents - ecosystems - oceans A:
A: oceans

Q: Q: What is never lost and just changes forms? Read this paragraph and choose the correct option from the provided answers: This platform is about to change energy from potential to kinetic. The energy is not lost; it just changes forms. The is on top of a precipice. The rest of the ride runs on the potential energy the platform has when it is at the top. Choices: - life - food - fuel - energy A:
A: energy

Q: Q: The uterus has an external opening known as what? Read this paragraph and choose the correct option from the provided answers: Nervous system Most nematodes possess four longitudinal nerve cords that run along the length of the body in dorsal, ventral, and lateral positions. The ventral nerve cord is better developed than the dorsal or lateral cords. All nerve cords fuse at the anterior end, around the pharynx, to form head ganglia or the "brain" of the worm (which take the form of a ring around the pharynx) as well as at the posterior end to form the tail ganglia. In C. elegans, the nervous system accounts for nearly one-third of the total number of cells in the animal. Reproduction Nematodes employ a variety of reproductive strategies that range from monoecious to dioecious to parthenogenic, depending upon the species under consideration. elegans is a monoecious species and shows development of ova contained in a uterus as well as sperm contained in the spermatheca. The uterus has an external opening known as the vulva. The female genital pore is near the middle of the body, whereas the male's is at the tip. Specialized structures at the tail of the male keep him in place while he deposits sperm with copulatory spicules. Fertilization is internal, and embryonic development starts very soon after fertilization. The embryo is released from the vulva during the gastrulation stage. The embryonic development stage lasts for 14 hours; development then continues through four successive larval stages with ecdysis between each stageL1, L2, L3, and L4ultimately leading to the development of a young male or female adult worm. Adverse environmental conditions like overcrowding and lack of food can result in the formation of an intermediate larval stage known as the dauer larva. Choices: - cervix - ovaries - fallopian tubes - vulva A:
A: vulva