Why is water sometimes called the "universal solvent"?.
A. Because water dissolves all solutes equally well.
B. Because water is a nonpolar solvent.
C. Because water is good at dissolving ions and polar molecules.
D. Because water is poor at dissolving nonpolar molecules.
Water is sometimes called the “universal solvent” because it dissolves more substances than any other liquid.
This is due to its polarity and ability to form hydrogen bonds, which allows it to dissolve ions and polar molecules.
Choice A) Because water dissolves all solutes equally well is incorrect because water does not dissolve all solutes equally well.
Choice B) Because water is a nonpolar solvent is incorrect because water is a polar solvent.
Choice D) Because water is poor at dissolving nonpolar molecules is incorrect because it does not explain why water is called the “universal solvent”.
Therefore, the Correct Answer is C.
More Questions on TEAS 7 Science
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Q #1: Which of the following is true regarding the role of oncogenes in cancer development?
A. Mutations in oncogenes always result in the inhibition of cell division.
B. Oncogenes are only found in human cells and not in any other organism.
C. Genes that regulate cell division are not found in any viruses.
D. Genes that regulate cell division can become oncogenes when mutated.
Answer Explanation
The correct answer is choice D.
Genes that regulate cell division can become oncogenes when mutated.
Oncogenes are mutated genes that can contribute to the development of cancer.
In their non-mutated state, everyone has genes which are referred to as proto- oncogenes.
When proto-oncogenes are mutated or increased in numbers due to DNA damage, the proteins produced by these genes can affect the growth, proliferation, and survival of the cell, and potentially result in the formation of a malignant tumor.
Choice A is incorrect because mutations in oncogenes do not always result in the inhibition of cell division.
Instead, they can contribute to the development of cancer by affecting cell growth.
Choice B is incorrect because oncogenes are not only found in human cells but can be present in other organisms as well.
Choice C is incorrect because genes that regulate cell division can be found in viruses. -
Q #2: What is hydrogen bonding?
A. The attraction between the relatively positive areas of one molecule and the relatively negative areas of another molecule.
B. The repulsion between the positive and negative charges of two molecules.
C. The attraction between two nonpolar molecules.
D. The attraction between two ionic molecules.
Answer Explanation
Hydrogen bonding is an interaction involving a hydrogen atom located between a pair of other atoms having a high affinity for electrons.
One atom of the pair (the donor), generally a fluorine, nitrogen, or oxygen atom, is covalently bonded to a hydrogen atom, whose electrons it shares unequally; its high electron affinity causes the hydrogen to take on a slight positive charge.
The other atom of the pair (the acceptor), also typically F, N, or O, has an unshared electron pair, which gives it a slight negative charge.
Mainly through electrostatic attraction, the donor atom effectively shares its hydrogen with the acceptor atom, forming a bond.
Choice B) The repulsion between the positive and negative charges of two molecules is incorrect because hydrogen bonding involves attraction, not repulsion.
Choice C) The attraction between two nonpolar molecules is incorrect because hydrogen bonding involves polar molecules.
Choice D) The attraction between two ionic molecules is incorrect because hydrogen bonding involves polar molecules and not ionic molecules.
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Q #3: A nurse is caring for a patient who has been declared brain dead and is awaiting organ donation. Which of the following interventions is most important to preserve the viability of the organs?
A. Administering antibiotics to prevent infection.
B. Maintaining normal body temperature and blood pressure.
C. Providing emotional support to the family members.
D. Applying eye drops and ointment to prevent corneal drying.
Answer Explanation
The correct answer is choice B.
Maintaining normal body temperature and blood pressure.
Early identification and management of potential organ donors must take into consideration specific pathophysiologic changes for medical optimization 1.
The VIPPS (ventilation, infusion and pumping, pharmacological treatment, and specificities) strategy is a mnemonic method that brings together key aspects of the restoration of oxygen delivery to tissues during hemodynamic instability plus organ optimization strategies.
Choice A is incorrect because administering antibiotics to prevent infection is not the most important intervention to preserve organ viability.
Choice C is incorrect because providing emotional support to family members, while important, is not an intervention that directly affects organ viability.
Choice D is incorrect because applying eye drops and ointment to prevent corneal drying is not the most important intervention to preserve organ viability.
