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Chemistry answers to 59 questions
Proteins are polymers, not lipids since they have long sequences of amino acids. Lipids are known for their single structure made of glycerol and three fatty acids. A polymer is a large molecule made of several monomers. A monomer is…
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A mole is a unit of measurement that is assigned to the quantity of any substance. It is the molarity of a given substance, and it is often measured in mols per meter. A molecule is a group of atoms…
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Iron has 2 valence electrons. Valence electrons refer to the number of electrons that an element has in its outermost shell. This outermost electron is referred to as the ionization power of an atom. This means the number of electrons…
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Answer: D. Sugar burns when heated on a skillet. A chemical reaction is one that when it occurs, new substances are formed, and it is not easily reversible by simple chemical processes. A. When sugar dissolves in water, no new…
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D. Nitrogen. Greenhouse gases are gases that transfer heat from the sun's heat in one-way traffic. As these gases increase, they expand, causing heat to enter the Earth through the atmosphere, but they refuse to allow these radiations to leave…
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The correct answer is B. They are consumed by the reactions they catalyze
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The most reactive group of elements on the periodic table are elements in Group 1. They are highly reactive because the distance between the outermost electron and the nucleus increases as you move further down the group. These elements are…
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Despite the sharp variations in their functions, acids and bases have a few similarities. a. Both acids and bases are water-soluble. They dissolve in water to become diluted. b. Both acids and bases are good conductors of electricity. c. When…
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An atom is the smallest component of an element, while a molecule is made up of two or more atoms. While atoms comprise protons, neutrons, and electrons, molecules comprise two or more atoms that are combined chemically. Atoms cannot be…
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Hello! As a rule, chromosomes become visible during prophase, so, the correct version is B. Prophase is the first and the longest phase of mitosis, and during this stage nuclear membrane breaks down and chromosomes become visible.
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Correct answer is B - dipole-dipole. Dipole-dipole interaction is much stronger than London dispersion forces, but weaker than covalent or ionic bonds. It equals 5-10 kJ per mole.
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In this case, you should use the formula for finding the maximum number of stereoisomers for a compound: N max = 2m, where n = the number of chiral centers So, the calculations for your example will look as follows:…
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As a rule, we use roman numerals in the name of a compound when a metal cation forms two ions with different states of oxidation. For instance, Cu can form two different ions - Cu+ and Cu 2+. Combining with…
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Atomic mass is a mass of a single atom, it can be calculated as a sum of neurons and protons in the atom. In turn, a molar mass is a mass of a substance (in grams) divided by the number…
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Here's the answer: When an atom emits an alpha particle, it transforms into a different element, therefore, its atomic number will be reduced by two.
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Water can dissolve the ionic compound because of the diference between its hydration and lattice energy.
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The given mass of an element can be found using Avogadro's number, which equals 6.02214076 × 1023 mol-1 and gives you one mole of anything. 1. You determine the molar mass of the element. 2. Then, you divide the given…
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Correct answer is 1. MgO is expected to have the highest lattice energy.
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Hi there! BrCl3 is definitely a polar molecule, it is evident from its T-shaped molecular geometry.
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No of protons - 29 No of neutrons - 35 No of electrons - 29 Explanation: Since the atomic number of copper is 29, the number of protons equals 29 as well. Since the atom is neutral, the number of…
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First, you should write a molecular equation: MgCl2(aq) + 2NaOH(aq) ==> Mg(OH)2(s) + 2NaCl(aq) Then, the net ionic reaction will equal: Mg^2(aq) + 2OH^-(aq) ==> Mg(OH)2(s)
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Here's the solution: The rate of the reaction is R R = - 1/5 * (d*[Br2])/dt The average rate of consumption of bromine is 1.76 * 10-4 M/s, therefore, - d*[Br]/dt = 1.76 * 10-4 M/s The average rate of…
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First, let's define the standard enthalpy values (H): 02(g) = 0 kj/mol CO2 (g) = -393.5 kj/mol H20(g) = -241.8 kj/mol According to the instructions, heat per mole produced (H) equals 5094 kj Therefore, -5094 kj is your H total.…
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First of all, we need to find the average rate if disappearence for A, where the formula is -ΔC/Δt First rate (A) = -ΔC/Δt = - (0.430-0.720)/(196-0) = 1.48 * 10-3 mol/(L*s) Second rate (A) = -Δc/Δt = - (0.140-0.430)/(392-196)…
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The first step should be writing out a balanced equation. To do that, you should remember that ethanol is a hydrocarbon derivative and burns the same ways as hydrocarbons yielding H20 and CO2 as end products. With that in mind,…
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The solubility of Copper Sulphate will decrease. That’s why precipitate CuSO*5H2O will be formed.
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Solution: N2(g)+2O2(g)-->2NO2(g) ?H°1=+66.4kJ 2NO2(g)--> 2NO(g)+O2(g) ?H°2=+114.2kJ Add the rxns to get an answer: N2(g)+2O2(g)-->2NO2(g) ?H°1=+66.4kJ 2NO2(g)--> 2NO(g)+O2(g) ?H°2=+114.2kJ So the answer is N2(g) + O2(g) --> 2NO(g) 66.4kJ + 114.6 kJ = 181kJ.
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F - false T - true a.It is an organic molecule. - T b.It contains thirteen different chemical elements. - F c.Its chemical formula can be written as C3H7NO2. - depends on writing - T d.Each of the carbon atoms…
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Answer: Alkyl halides contain C-Hal bond. The bond is polar, because halogens are more polar that Carbon. There are dipole-dipole interactions between alkyl halides. Water also polar molecule, but there are hydrogen bonds between these molecules. When water and an alkyl…
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