化学
化学反应、化学计量、分子结构与元素性质。
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what kind of intermolecular forces act between a hydrogen fluoride mole…
London dispersion forces, dipole - dipole forces, hydrogen bonding
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21 multiple choice 4 points an atom has 20 protons and 20 electrons. ho…
20 (The second option in the multiple - choice list)
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how many neutrons are in uranium - 238 if it has 92 protons? 146 238 92…
146
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multiple choice 4 points how many protons are in an atom of nitrogen - …
7
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what kind of intermolecular forces act between a water molecule and a c…
ion - dipole force
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how many neutrons are in nitrogen-15? helium 2 he 4.0026 neon 10 ne 20.…
8
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14 multiple choice 4 points how many protons are in the isotope sulfur …
16
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what kind of intermolecular forces act between a fluorine (f2) molecule…
London dispersion force
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12 multiple choice 4 points a neutral atom has 12 protons. how many ele…
C. 12
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an atom has 82 protons and a mass number of 208. how many neutrons does…
A. 126
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what kind of intermolecular forces act between two carbon monoxide mole…
Dipole - dipole forces, London dispersion forces
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what kind of intermolecular forces act between two carbon monoxide mole…
London dispersion forces, dipole - dipole forces
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an atom has 19 protons and 20 neutrons. what is its mass number? 19 20 …
39
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9 multiple choice 1 point how many neutrons are in sulfur - 34? helium …
18
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8 multiple choice 1 point how many neutrons are in uranium - 238 if it …
A. 146
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how many neutrons are in carbon - 14? helium 2 he 4.0026 boron 5 b 10.8…
8
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what kind of intermolecular forces act between a methanol (ch3oh) molec…
Hydrogen bonding, London dispersion forces
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multiple choice 1 point what is cohesion in relation to water? water mo…
Water molecules sticking together
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which of the following best describes a polar covalent bond? a bond in …
A bond where electrons are shared unevenly between two atoms, resulting in a partial charge.
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3 multiple choice 1 point what is true about nonpolar covalent bonds? e…
Electrons are shared equally between atoms with similar electronegativities.
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multiple choice 1 point which of the following are molecules that have …
D. Isomer
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fill in the missing words note to students: for molar mass values, use …
One mole of water weighs $18.02$ grams. Molar mass of water is $18.02$ g/mol. One mole of zinc chloride weighs $136.28$ grams. Molar mass of zinc chloride is $136.28$ g/mol. One m…
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what kind of intermolecular forces act between a chloroacetylene (c2hcl…
Ion - dipole forces, London dispersion forces
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age of science 1747 andreas marggraf discovers that beet sugar is ident…
B. It documents key events in the sugar and sweetener industries
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multiple choice question orange juice fortified with calcium, yogurt pr…
B. functional foods
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multiple choice question when compared to plant foods, nutrient supplem…
D. phytochemicals
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fill in the missing words note to students: for molar mass values, use …
One mole of zinc metal weighs 65.38 grams. The molar mass of zinc is 65.38 g/mol. One mole of calcium metal weighs 40.08 grams. The molar mass of calcium is 40.08 g/mol. One mole …
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question 6 (2.5 points) molecules that contain carbon, hydrogen, and ox…
D. organic compounds
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multiple choice question in order to obtain nutrients and phytochemical…
C. eat a variety of "whole" and minimally processed foods
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molecules known as amino acids are the building blocks of proteins. 1) …
1) 1) True 2) 1) True 3) Away from the mid - line of the body
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multiple choice question which of these statements describes a key conc…
C. Since no naturally occurring food contains all nutrients in amounts your body needs, variety is important
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fill in the missing words mole of zinc contains 6.022x10^23 atoms of zi…
1 0.5
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1. (a) define the term polymerization. (b) state three characteristics …
(a) The process by which monomers combine to form polymers through chemical reactions. (b) Forward and reverse rates are equal; Concentrations of reactants and products are consta…
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multiple select question select all that apply choose the reasons it is…
A. Foods naturally contain beneficial combinations of nutrients and phytochemicals B. Nutrients from foods can sometimes be more available than nutrients from supplements D. Foods…
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water is often called the \universal solvent\ because many substances c…
polarity and cohesion
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multiple choice question the most natural and economical way to obtain …
C. a variety of "whole" and minimally processed foods
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question 7 what is a complimentary color scheme? using two colors oppos…
Using two colors opposite on the color wheel.
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hydrogen bonds in water molecules are formed between ____. o nuclei of …
Hydrogen and oxygen atoms of adjacent molecules
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rank the elements or compounds in the table below in decreasing order o…
D, C, Cr, Ar
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question 5 1 pts large bodies of water, such as lakes and oceans, do no…
Question 5: Water has a high heat capacity. Hydrogen bonds in water molecules are formed between: Hydrogen and oxygen atoms of adjacent molecules.
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question 2 anselm reyles artwork that is made up of 119 glowing neon tu…
Diagonal lines feel active like they have movement.
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1. (a) define the term polymerization. (b) state three characteristics …
(a) Polymerization is the combination of monomers to form polymers. (b) Equal forward and reverse rates; constant concentrations; dynamic at molecular level. (c) $CaSO_4$ coating …
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drop each substance in the correct category substance dissolved in wate…
Substance dissolved in water: $C_{6}H_{12}O_{6}(aq)$, $CO_{2}(aq)$, $NaHCO_{3}(aq)$ Substance in a liquid form (pure): $Br_{2}(l)$, $H_{2}O(l)$ Solid substance: $C_{6}H_{12}O_{6}(…
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rank the elements or compounds in the table below in decreasing order o…
D, C, B, A
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match the property of water with its description. choose choose choose …
High heat capacity - Water can absorb a lot of energy before changing temperature. Density - This causes solid water to float on liquid water. Cohesion - Water molecules stick to …
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rank the elements or compounds in the table below in decreasing order o…
1. $Al_2O_3$ 2. Substance with Lewis structure (ethanol) 3. $CO$ 4. $O_2$
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fill in the missing words in the reaction 2ag⁺(aq) + zn(s) → 2ag(s) + z…
reduced, oxidized, oxidizing agent, reducing agent, ionic equation
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fill in the missing words in redox reaction metals in their elemental f…
reducing; lose; oxidized
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select the correct answer. waters heat of vaporization is 2,257 joules/…
E. 25,300 J
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end of semester test takes place: mgbr₂(aq) + k₂co₃(aq) → mgco₃(s) + 2k…
D. 4.2 M
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rank the elements or compounds in the table below in decreasing order o…
1. $H_2O$ 2. $HgCl_2$ 3. $HCl$ 4. $H_2$
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fill in the missing words reactions that involve transfer of electrons …
Reactions that involve transfer of electrons between particles (atoms, molecules, ions) are called **redox** reactions. Reduction is the **gain** of electrons. Oxidation is the **…
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read the excerpt from levitt and dubners freakonomics. driving around t…
the size of his business
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read shakespeares sonnet 100 where art thou, muse, that thou forgetst s…
C. cdcd
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end of semester test 38 select the correct answer. among these properti…
E. sour taste
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liquid a is known to have a lower vapor pressure and lower surface tens…
1. Eventually both liquids boil, B first and then A. 2. $V_A$ will be greater than $V_B$
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if morality represents the way we would like the world to work and econ…
to lend credibility and additional support to their conclusion
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liquid a is known to have a higher vapor pressure and higher viscosity …
It's impossible to predict whether $V_A$ or $V_B$ will be greater without more information. It's impossible to predict whether either liquid boils without more information.
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drag each quantity to the correct location on the table. complete the t…
| | Bond Energy | Bond Length | |--|--|--| | N - N | 167 kJ/mol | 145 pm | | N = N | 418 kJ/mol | 125 pm | | N≡N | 942 kJ/mol | 110 pm |
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liquid x is known to have a lower viscosity and lower vapor pressure th…
First experiment: \(p_X\) will be less than \(p_Y\) Second experiment: \(t_X\) will be less than \(t_Y\)
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decide which intermolecular forces act between the molecules of each co…
| compound | dispersion | dipole | hydrogen - bonding | | ---- | ---- | ---- | ---- | | $Cl_2$ | Yes | No | No | | carbon tetrabromide | Yes | No | No | | $CH_2Cl_2$ | Yes | Yes |…
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type the correct answer in the box. sodium carbonate (na₂co₃) is someti…
109
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decide which intermolecular forces act between the molecules of each co…
| compound | dispersion | dipole | hydrogen - bonding | |--|--|--|--| | SiH₄ | √ | | | | HClO | √ | √ | √ | | COS | √ | √ | | | CH₂O | √ | √ | |
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decide which intermolecular forces act between the molecules of each co…
| compound | dispersion | dipole | hydrogen - bonding | | ---- | ---- | ---- | ---- | | hydrogen fluoride | √ | √ | √ | | methane ($CH_4$) | √ | | | | chloromethane ($CH_3Cl$) | √…
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34 select the correct answer. a compound has a molecular weight of 112.…
A. \(C_6H_8O\)
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read shakespeares sonnet 19 devouring time, blunt thou the lions paws, …
- the abab, cdcd, efef, gg rhyme scheme - the widespread use of iambic pentameter - the use of three quatrains followed by a couplet
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use the observation in the first column to answer the question in the s…
1. Substance A 2. Substance C 3. Substance E
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32 select the correct answer. which action would reduce the activation …
A. adding a catalyst to the reaction
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type the correct answer in the box. given: cac₂ + n₂ → cacn₂ + c in thi…
$92.7$
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use the observation in the first column to answer the question in the s…
Substance F Substance A Substance C
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use the observation in the first column to answer the question in the s…
1. Substance B 2. It's impossible to know without more information 3. Substance F
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29 select the correct answer. use the periodic table to determine what …
D. $^{135}_{56}Ba$
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28 select the correct answer. how many atoms of n are in 137.0 grams of…
D. $2.171\times 10^{24}$
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27 select the correct answer. what is the empirical formula of a compou…
D. \(Al_2S_3\)
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use the observation in the first column to answer the question in the s…
Substance D Substance F Substance A
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select the correct answer from each drop - down menu. for a gas to be s…
First drop - down: polar Second drop - down: low Third drop - down: high
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use the observation in the first column to answer the question in the s…
1. Substance A 2. Substance D 3. Substance F
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noemi is writing an essay on organic foods. she wishes to include prope…
A. She could summarize the ideas from the source C. She could paraphrase the ideas from the source D. She could directly quote the ideas from the source
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24 select the correct answer. what is the molar mass of alcl₃? a. 62.43…
D. 133.33 g/mol
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23 select the correct answer. which statement correctly relates two sub…
C. $NH_4^+$ is the conjugate acid of $NH_3$.
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drop each atom/ion in the correct category. an atom/ion with the oxidat…
An atom/ion with the oxidation number + 7: Mn in \(KMnO_4\), Cl in \(Cl_2O_7\) An atom/ion with the oxidation number + 4: Pb in \(PbO_2\), V in \(VCl_4\) An atom/ion with the oxid…
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this graph shows how the vapor pressure of three liquids varies with te…
most volatile: acetone least volatile: benzene acetone: 56 methanol: 65 benzene: 80 less
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22 drag each label to the correct location. identify the molecular shap…
trigonal pyramidal, tetrahedral, trigonal planar, bent
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this graph shows how the vapor pressure of three liquids varies with te…
most volatile: tetrahydrofuran least volatile: isopropyl acetate tetrahydrofuran: 66 cyclohexane: 81 isopropyl acetate: 89 less
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this graph shows how the vapor pressure of three liquids varies with te…
most volatile: hexane least volatile: isopropyl acetate hexane: 69 ethanol: 78 isopropyl acetate: 89 more
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which statements describe iambic pentameter as it is used in shakespear…
- Each line contains five metrical feet. - In a group of two syllables, the second is stressed.
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fill in the missing words if the following reaction is balanced correct…
The coefficient in front of $O_{2}$ is 13, and the coefficient in front of $H_{2}O$ is 10.
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fill in the missing words if the following reaction is balanced correct…
The coefficient in front of $H_2$ is 3, and the coefficient in front of $Al$ is 2.
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fill in the missing words. if the following reaction is balanced correc…
The coefficient in front of $NaOH$ is 2, and the coefficient in front of $H_2O$ is 1.
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fill in the missing words interpret the following reaction by filling i…
Solid; Aqueous; Gas; Liquid; Reactants; Products
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4. interpret a chemical equation of decomposition of hydrogen peroxide …
Hydrogen peroxide in a water - solution in the presence of potassium iodide decomposes producing oxygen gas and liquid water.
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3. two equations below look like they are balanced, and they are, but t…
a) The coefficients are not in the simplest ratio. Correct equation: $Mg(OH)_2(s)+2HCl(aq) ightarrow MgCl_2(aq) + 2H_2O(l)$ b) Coefficients should be whole - numbers. Correct equa…
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how did the lewis and clark expedition create a contradiction in jeffer…
It required federal funding despite Jefferson's opposition to government programs.