Chemistry
Chemical reactions, stoichiometry, molecular structures, and element properties.
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intermediate level problems: 6. the following are the results of analys…
The two samples are different compounds, and the data follows the law of multiple proportions.
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adhesive forces between water molecules and glass molecules help water …
Water rises farther in a narrow glass tube than in a wide glass tube. Water molecules are held together by hydrogen bonds as they rise in a capillary tube.
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a scoop - shaped concave meniscus forms when adhesive forces between a …
oil: Cohesive forces are greater than adhesive forces. water: Adhesive and cohesive forces are equal. mercury: Adhesive forces are greater than cohesive forces.
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water molecules are also attracted to other kinds of molecules. this is…
A concave meniscus forms in a glass column when adhesive forces between water and glass are greater than cohesive forces between water molecules.
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in chemistry class, teresa was aware that she was writing down her teac…
consciously aware of her experience.
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dr. liza conducted a sleep study in which half of the volunteers were r…
Melatonin
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determine whether each statement is true or false. water molecules at t…
Water molecules at the surface form hydrogen bonds with only the molecules next to and below them: False Molecules at the surface of water repel molecules below the surface: False…
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estimate large and small quantities quick check the radius of a hydroge…
0.000000053
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polar water molecules form hydrogen bonds with each other. in liquid wa…
A slightly negative oxygen atom in a water molecule forms a hydrogen bond with a slightly positive hydrogen atom in another water molecule.
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water is made of one oxygen atom covalently bonded to two hydrogen atom…
In a molecule of water, the oxygen atom shares electrons with each hydrogen atom. Oxygen also has two non - bonding pairs of valence electrons. Because valence electrons are more …
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the rhyme pattern that occurs at the ends of lines in poetry is called …
D. a rhyme scheme
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what are the characteristics of fixed poetry? select three options. a r…
a regular rhyme scheme, lines of equal length, a set number of lines
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use the phase diagram of substance x below to find the melting point of…
(Assuming the graph reading gives $T_{K} = 300$ K) $T_{C}=300 - 273.15=26.85^{\circ}C$ (The actual value will depend on the accurate reading from the given phase - diagram)
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question 5 (1 point) indicate whether the following sentence is true (t…
False
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29 matching 1 point please match the element to its kind. argon chlorin…
Argon - Noble gas Chlorine - Non - metal Sodium - Metal Iron - Metal Oxygen - Non - metal
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consider the same reaction: 2 molecules of ethylene (c₂h₄) react with 1…
2
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2. how does the change in energy of a chemical reaction predict whether…
2. A negative Gibbs free - energy change ($\Delta G$) indicates a spontaneous reaction likely to occur; positive $\Delta G$ means non - spontaneous; $\Delta G = 0$ is equilibrium.…
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acetaldehyde is a substance commonly used in chemical factories. it is …
H: 8 C: 4 O: 2
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13 fill in the blank 5 points atoms of the same element that have diffe…
13. Isotopes 14. Physical
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consider the same reaction: 1 molecule of nitrogen (n₂) reacts with 3 m…
2
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3. explain are all compounds molecules? why or why not? 4. compare ioni…
No, because some compounds like ionic compounds are not held together by covalent bonds to form molecules. ### 4.
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10 numeric 1 point what is the atomic number of sulfur? answer 11 numer…
10. 16 11. 22
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ammonia is commonly used as a fertilizer for plants. it is made when ni…
| Chemical element | Number of atoms in products | | ---- | ---- | | H | 6 | | N | 2 |
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question 2 of 12 points possible: 1.00 how can you improve your ability…
B. Place a piece of white paper under the analyte flask throughout the titration.
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6 fill in the blank 1 point the symbol for chlorine is type your answer…
6. Cl 7. 12 8. 29
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ethanol is a chemical that is used in many hand sanitizers. it is produ…
1
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2 fill in the blank 1 point the symbol for silicon is type your answer.…
The symbol for silicon is Si. The symbol for sodium is Na. The symbol for iron is Fe.
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use the phase - diagram of substance x below to find the temperature at…
(The specific temperature value needs to be read from the actual phase - diagram which is not provided with clear scale values in the description. But the process is as above to f…
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is region a likely hydrophobic or hydrophilic? explain your answer. due…
Region A is hydrophobic because it consists of long non - polar hydrocarbon chains. Region B is hydrophilic because it contains polar and charged functional groups (phosphate and …
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does cholesterol contain many partial charges, or very few partial char…
Cholesterol can form very few hydrogen bonds with water, because it has very few partial charges.
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part 1 analyze the overall structure of cholesterol. how does the numbe…
Part 1: Cholesterol has more nonpolar covalent bonds than polar covalent bonds. Part 2: Very few, because it is primarily made of nonpolar bonds.
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in an atom, in stable atoms, the number of protons, the number of neutr…
| Element | Atomic # | Atomic Mass (Rounded to the whole number) | # of Protons | # of Neutrons | # of Electrons | |---|---|---|---|---|---| | Hydrogen (H) | 1 | 1 | 1 | 0 | 1 | |…
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9 fill in the blank 1 point when comparing the ionization energies betw…
1. Phosphorus 2. stronger 3. remove a valence electron
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the educated reader uses the language of authors craft to discuss liter…
To answer the question, one must first identify poetic elements like imagery, metaphor, rhyme - scheme, etc. in "Recuerdo". Then, analyze how each element contributes to the theme…
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multiple choice 1 point which element has a higher ionization energy an…
C. Bromine. More energy is needed to remove an electron because there is more attraction between the valence electrons and the protons in the nucleus.
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6 fill in the blank 1 point when comparing the ionization energies betw…
1. Platinum 2. stronger 3. remove an electron
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5 multiple choice 1 point which element requires more energy to remove …
B. Carbon
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4 fill in the blank 1 point which element requires more energy to remov…
Bromine
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3 multiple choice 1 point which element shown below requires more energ…
A. Radon
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2 multiple choice 1 point which element shown below requires more force…
B. Krypton
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exit ticket: ionization energy 1 fill in the blank 1 point for elements…
more protons
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in words, the expression means: oxygen is more electronegative than nit…
O:——C
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lets put some of these ideas together. summarize the information you ju…
- Bond polarity is caused by differences in electronegativity. - Bond polarity results in partial positive and partial negative charges on the atoms involved. - With respect to el…
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9 0/1 point consider the elements listed below: zirconium strontium tin…
1. **Question 9**: Tin has the strongest coulombic attraction among Zirconium, Strontium, Tin, Silver. 2. **Question 10**: Aluminum has a stronger force of attraction between the …
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the ball - and - stick model below is of a sugar called glucose. (gluco…
C. The correct molecular formula for glucose is \(C_{6}H_{12}O_{6}\) D. Glucose contains 6 carbon atoms, 6 oxygen atoms, and 12 hydrogen atoms.
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13 multiple choice 1 point why does nickel (ni) have more coulombic att…
Nickel has less energy levels causing the valence electrons to be closer to the protons in the nucleus.
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lets check your understanding. drag and drop the correct structural for…
Ammonia $NH_3$: The structural formula with a nitrogen atom in the center and three hydrogen atoms bonded to it. Water $H_2O$: The structural formula with an oxygen atom in the ce…
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drag and drop the correct molecular formula to match it with each molec…
First molecule: $NH_3$ Second molecule: $H_2O$
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12 fill in the blank 1 point when comparing magnesium (mg) and phosphor…
Phosphorus; are in the same period; phosphorus has more protons; a higher effective - nuclear charge
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11 multiple choice 1 point why does oxygen (o) have a stronger coulombi…
Oxygen's valence electrons are on the same energy level as Carbon's causing their valence electrons to be about the same distance from the nucleus. However, Oxygen has more proton…
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rank the amount of time that a water molecule spends in each of the fol…
Living things (plants & animals), Rivers, Lakes and swamps, Groundwater
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10 fill in the blank 1 point when comparing the coulombic attraction be…
- First blank: Gallium (Ga) - Second blank: Gallium (Ga) - Third blank: closer to
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9 fill in the blank 1 point consider the elements listed below: zirconi…
Silver
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consider the four models of the carbon (c), oxygen (o), nitrogen (n), a…
Nitrogen - 3 unpaired electrons Oxygen - 2 unpaired electrons Hydrogen - 1 unpaired electron Carbon - 2 unpaired electrons
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groundwater aquifers are only renewable if ____________(complete this s…
Question 8: we use the water in them at a rate slower than they are able to replenish. Question 9: True
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consider the four models of the carbon (c), oxygen (o), nitrogen (n), a…
Oxygen: 2 unpaired electrons Hydrogen: 1 unpaired electron Carbon: 2 unpaired electrons
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the diagram below represents a molecule made of five atoms connected by…
Arrow 2
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a quick side note: representations like the one above are called “model…
C. $H^{+}$
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determine the name of each compound. use r cuo: cu₂o: crs: cr₂s₃: febr₂…
CuO: Copper(II) oxide Cu₂O: Copper(I) oxide CrS: Chromium(II) sulfide Cr₂S₃: Chromium(III) sulfide FeBr₂: Iron(II) bromide FeBr₃: Iron(III) bromide
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8 fill in the blank 1 point consider the elements listed below: iodine …
Fluorine
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the atoms that make up different elements share other key characteristi…
- Carbon's outer electron shell contains four electrons. - The carbon nucleus contains 6 protons and 6 neutrons.
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which statements accurately describe the model of the carbon atom above…
- Carbon's outer electron shell contains four electrons. - True - If this model showed a nucleus with seven protons, it would still represent carbon. - False - Carbon's electrons …
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7 fill in the blank 1 point elements in the same choose your answer... …
1. period 2. protons 3. greatest
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chemistry: fundamentals and davidson give the systematic name of each c…
\(P_2S_5\): diphosphorus pentasulfide \(CO\): carbon monoxide \(P_3N_5\): triphosphorus pentanitride
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6 fill in the blank 1 point as the number of energy levels increases, t…
First blank: more Second blank: less
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5 fill in the blank 1 point as the distance between a proton and valenc…
increases
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4 fill in the blank 1 point selenium (se) has type your answer... energ…
4 6
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5. a. provide one example of an endothermic or exothermic reaction (dif…
a. An example of an exothermic reaction is the combustion of methane. The chemical equation for the combustion of methane ($CH_4$) in the presence of oxygen ($O_2$) is $CH_4 + 2O_…
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3 fill in the blank 1 point silicon (si) has type your answer... energy…
First blank: 3 Second blank: 4
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2 fill in the blank 1 point barium (ba) has type your answer... energy …
6; 2
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exit ticket: coulombic attractions 1 fill in the blank 1 point an elect…
An electron is attracted to the protons in the nucleus. An electron is repelled by the other electrons in the atom.
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which of the following are the types of scientific models? select all t…
A. conceptual, C. physical, D. mathematical
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43 complete subjects and predicates the complete subject of a sentence …
**Practice A - Identifying Simple and Complete Subjects**: 1. Complete subject: My dad's carpentry job; Simple subject: job 2. Complete subject: The school cafeteria; Simple subje…
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question 14 of 22 general chemistry 4th edition mcquarrie • rock • gall…
sodium sulfite: $Na_2SO_3$ potassium phosphate: $K_3PO_4$ silver sulfate: $Ag_2SO_4$ ammonium nitrate: $NH_4NO_3$
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the following picture would be best described as
A. a liquid mixture
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which of the following is an extensive property of the element carbon? …
D. The mass of a carbon sample
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which of the following is an example of an intensive property of a bar …
A. The bar has a density of 19.2 g/mL.
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multiple - choice question what is elastic potential energy? energy sto…
Energy stored in objects that are stretched or compressed
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answer: a a liquid compound b a gaseous mixture c a gaseous compound d …
C. a gaseous compound
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variables hw check a class investigates how temperature affects the rat…
Amount of sugar - Constant Room temperature group - Control group Temperature of water - Independent variable Time for sugar to dissolve - Dependent variable
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multiple - choice question nuclear potential energy is similar to what …
C. Chemical Potential Energy
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at the temperatures specified, identify the following substances as a s…
1. Solid 2. Plasma 3. Liquid 4. Gas 5. Solid 6. Liquid 7. Gas 8. Liquid 9. Compound 10. Homogenous mixture 11. Homogenous mixture 12. Element 13. Heterogeneous mixture 14. Compoun…
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multiple - choice question what kind of energy does firewood, batteries…
Chemical Potential Energy
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identify the symbol for each element 1 oxygen o 2 hydrogen h 3 chlorine…
| Element | Symbol | Atomic Number | Period | Group | | ---- | ---- | ---- | ---- | ---- | | Sodium | Na | 11 | 3 | 1 | | Oxygen | O | 8 | 2 | 16 | | Krypton | Kr | 36 | 4 | 18 | …
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1. what effects did the heating or freezing time have on the outcomes o…
Heating or freezing time can impact texture, flavor, and physical - chemical properties of food in cooking experiments.
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which would show an example of how physical changes are reversible? cut…
melting tin and then cooling it into a mold
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a graduated cylinder is filled with 100.0 ml of water. the cylinder is …
Sample A > Sample B > Sample C
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which is a characteristic of atoms? they come in ten major types. they …
They are the smallest units of matter.
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3. describe what happens to the particles in a berry sauce mixture as i…
The particles gain kinetic energy and move more rapidly, some may change to the gas phase through evaporation.
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4. what are the characteristics of an extensive property of matter? 5. …
4. Depends on amount of matter. 5. Cement, pea soup, apple sauce. 6. Does not depend on amount of matter. 7. Salt water, air, stainless steel. 8. Mass, volume. 9. Homogeneous. 10.…
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6al₂(so₄)₃ al= s= o=
$Al = 12$, $S = 18$, $O = 72$
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2. describe what happens to the particles in an ice cream mixture as it…
As the ice - cream mixture freezes, the water molecules slow down and arrange into a crystalline structure, and the movement of all particles decreases due to loss of kinetic ener…
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why is matter so diverse in its properties and characteristics? differe…
Different combinations of various atoms result in a wide range of matter.
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what happens to the total mass of a substance undergoing a physical cha…
It stays the same.
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multiple choice identify the choice that best completes the statement o…
1. (No options provided in the question for this part, but based on the concept of heterogeneous mixture, the correct illustration should show non - uniform particle distribution)…
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which property of physical changes explains why matter is conserved in …
The bonds between atoms do not break; it is only the arrangement that changes.
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9. 3pb₃(po₄)₄ pb= p= o=
$Pb = 9$, $P = 12$, $O = 48$
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uranium is a type of atom. in special circumstances that usually involv…
It must be a different kind of atom.
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7. 4al₂(so₄)₃ al= s= o=
Al = 8, S = 12, O = 48
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6. 2pb(no₃)₂ pb= n= o=
$Pb = 2$, $N = 4$, $O = 12$