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Chemistry answers to 59 questions
Answer: B. It is ductile. Cesium is a very ductile metal with the second-lowest boiling point after mercury. It is liquid at room temperature and has chemical properties similar to that of potassium. Before failure, Cesium can sustain and withstand…
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Answer: B. Water molecules surround solute molecules. In the solubility of substances, the law that “like dissolves like” is strictly adhered to. Polar compounds are therefore soluble in polar solvents and non-polar compounds are soluble in non-polar solvents. Water is…
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Answer: A. O2 (oxygen gas) Oxygen gas was most likely not present in the primitive atmosphere of the earth. The atmosphere of primitive earth was composed mainly of carbon dioxide and methane as a result of the high level of…
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Answer: A. The higher the pH is, the more the hydroxide ion concentration decreases and the more acidic the solution becomes. Basic solutions are solutions with pH higher than 7 while acidic solutions are solutions with pH lower than 7.…
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Answer: D. It is a compound made of twenty-four total atoms of three different elements. Firstly, glucose is a compound composed of twenty-four atoms of which contain carbon, hydrogen, and oxygen. Option A is wrong because glucose as a molecule…
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Answer: B. Because of a reaction with water, feldspar is changed into clay minerals. Hydrolysis is simply the process whereby substances are broken down chemically by water. This depends on the solubility, oxidation, oxidation-reduction reaction, and the pH of the…
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Answer: B. Volatile organic compounds and Nitrogen Dioxide. Ozone is made up of three oxygen atoms and is formed when sunlight and heat lead to chemical reactions between nitrogen dioxide and a volatile organic compound also known as hydrocarbons. This…
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Answer: A. Energy The major products of fermentation are lactic acid, ethanol, hydrogen gas, and carbon dioxide. Fermentation involves the breaking down of substances containing sugar substances using chemical means which sometimes involves microorganisms with the release of heat. The…
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Answer: D. Must be a general statement. A proposed explanation, formulated on the grounds of limited evidence with the aim of further investigation is known as a hypothesis. For a hypothesis to be good enough to be adopted, it must…
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Answer: A. sodium Sodium is the most reactive element in the options listed. With an atomic number of 11, sodium is ready to give out one electron to create a fully stable L shell and attain an octet state. When…
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Answer: D. A mixture of a solid in another solid When the composition of a mixture is not uniform, such a mixture is called a heterogeneous mixture. With this, it is clear that two or more different phases are required…
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Answer: A. Observation The scientific method is generally used when conducting experiments as well as for exploring observations. In order to discover the link or relationship between cause and effect in a variety of applications and situations, the scientific method…
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In cellular respiration, chemical energy gotten from oxygen molecules and nutrients are converted to adenosine triphosphate coupled with the release of waste products. This is how cells get the energy they use. Cellular respiration involves four stages which are; glycolysis,…
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Answer: A. The enzyme influences the speed of change from substrate to product. By lowering the activation energy of the reaction, enzymes help to speed up rate of reaction without affecting the chemical composition of that reaction. Without enzymes in…
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Answer: A. It removes H2O from the atmosphere during glycolysis. Food particles are processed in aerobes by combining the food with oxygen and then diverting the energy gotten from it using the mitochondria. The energy is then stored using ATP…
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Answer: C. Acid dissolving limestone In chemical weathering, particles are disintegrated by a series of chemical reactions. Reactions like acidification, hydrolysis, oxidation, and carbonation, tend to alter the chemical composition of minerals. In limestone, rain mixes with carbon dioxide to…
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Answer: B. product The molecules upon which enzymes act are known as substrates. These substrates are later converted into different molecules known as products. Generally, enzymes, which are biological catalysts of the reactions of the body, are proteins with the…
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Answer: B. condensation. The process in which a substance changes from a gaseous state to a liquid state is called condensation, so option B is the correct answer. Absolute zero is the coldest possible temperature, where all motion stops. Evaporation…
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Answer: c. the Ca2+ ATPase of the sarcoplasmic reticulum The kind of transport system required to transport Ca2+ throughout the body is the active transport system. The Ca2+ ATPase found in the sarcoplasmic reticulum makes use of ATP as a…
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The order: NH3 > NH4NO3 > (NH4)2HPO4 > (NH4)2SO4 > KNO3 > (NH4)H2PO4 To calculate the mass percentage of nitrogen in a compound, we use Mass percentage= (mass element÷total mass of compound)×100 Nitrogen (N) is 14g/mol, and 2N Is 28g/mol…
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Acetylsalicylic acid, also known as aspirin, is formed by a series of repeating pi-bonds. These pi-bonds are made up of overlapping covalent bonds and are concentrated in some parts of the compound. The concentrations of pi-bonds are found where the…
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Answer: 4. the application of knowledge gained. Four main principles govern the scientific method. They are: • Making observations • Creating a hypothesis from the observation • Testing the hypothesis • Draw reasonable conclusions from the hypothesis Three of the…
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It is important to keep high acid food away from the coated tub because there would be a reaction between the food high in acid and the zinc-coated tub. The outcome of the reaction is Zinc salt which would contaminate…
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Answer: 2. CaO (s) + CO2 (g) → CaCO3 (s) and 4. PbCO3 (s) → PbO (s) + CO2 (g) In (2), limestone is decomposed under heating to give rise to quicklime and CO2, while (4), is the thermal decomposition…
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Even though acids and bases are fundamentally different in nature, there are some similarities between them. For example, both acids and bases cause a chemical reaction when applied to litmus paper -acid changes blue litmus paper to red, while bases…
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Answer: A. Periods. Explanation: The periodic table is divided into rows and columns. The rows run across the table from one end to the other and are called periods. The columns run from the top of the periodic table to…
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Answer: C. Tertiary structure. Explanation: The overall three-dimensional folded structure of a polypeptide is referred to as the tertiary structure. The structure is due to the relationship between the R-groups of the amino acids that constitute the building blocks of…
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Answer: B. Phosphorus is not abundant in the atmosphere, it comes mostly from the land and ocean. Explanation: The phosphorus cycle differs from other cycles because it does not particularly cycle through the atmosphere, unlike carbon. The phosphorus that exists…
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Answer: D. Energy. Explanation: Unlike carbon, nitrogen, water, and phosphorus which can be converted and recycled as it moves from one level of an ecosystem's food chain to another, energy can only be transferred from one form to another, but…
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Answer: High-spin complex ions: 4)[Co F6 ] 3- four unpaired e-'s 5)[Mn (H2O) 6 ] 2+ five unpaired e-'s Low-spin complex ions: 1) [Fe (CN)6 ] 4- no unpaired e- 2) [Fe (CN)6 ] 4- one unpaired e- 3) [Co…
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