化學
化學反應、化學計量、分子結構與元素性質。
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synthesize information a calcium atom tends to lose two electrons to be…
$CaCl_{2}$
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question 2 a ___ may oversee the actual work for the engineer by provid…
B. foreman
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question this is a kind of color map that allows an artist to quickly a…
D. color wheel
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organic chemistry study guide - academic part 1: define the following t…
- Organic Molecule: A molecule containing carbon - hydrogen bonds, often associated with living organisms. - Monomer: A small molecule that can bond with other monomers to form a …
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question artists use this kind of texture if they want to contradict a …
B. implied
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write in any formal charges not equal to zero. if there are none, pleas…
The formal charge on O is + 1.
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fill in the missing words a) the compound with the formula $n_2o_4$ is …
a) dinitrogen tetroxide b) bromine monochloride c) arsenic pentafluoride d) tetraphosphorus trisulfide e) hydrogen bromide
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question frank gehrys design for the guggenheim museum, bilbao, uses co…
C. organic and geometric forms
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question the human figure communicates the rich experience of humanity,…
D. organic
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why is water considered the universal solvent? water can dissolve only …
Water can dissolve more substances than any other liquid.
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10 multiple choice 0.25 points what conclusion can be drawn about the m…
The movement of water molecules becomes more random and chaotic.
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1. describe the major subatomic particles that make up an atom.
Protons are positively - charged particles found in the nucleus of an atom. Neutrons are neutral particles also located in the nucleus. Electrons are negatively - charged particle…
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question in the work the connectors, the artist james allen uses this k…
A. directional
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reading check compare how are ionic and covalent bonds alike? how are t…
**Similarities**: Both are chemical bonds that hold atoms together to form substances. **Differences**: Ionic bonds are formed by the transfer of electrons from a metal to a non -…
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select the true statements about density. density can be used to help i…
- Density can be used to help identify a substance. - The density of a substance does not depend on the size of the sample.
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classify each alkyl halide as primary (1°), secondary (2°), or tertiary…
Part 1 of 3: 2° Part 2 of 3: 3°
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a) covalent bonds form between two atoms of a nonmetal, an atom of a no…
b) molecular c) molecule d) the entire network
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draw the lewis structure for formic acid (ch₂o₂). formic acid molecules…
The Lewis structure has a carbon atom in the center. It is bonded to two hydrogen atoms with single bonds, to an oxygen atom (in the $-OH$ group) with a single bond and this oxyge…
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properties that vary depending on the amount of matter present are call…
extensive properties.
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a graduated cylinder contains 21.0 ml of water. when you place a gold r…
40.0 mL
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a graduated cylinder contains 21.0 ml of water. when you place a gold r…
$20.0\ mL$
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your own work choose one element of the first 10 in the periodic table …
Oxygen atom model: In the nucleus, there are 8 protons (represented by the large purple circle). There are 2 electrons in the first electron - orbit (inner circle) and 6 electrons…
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your own work choose one element of the first 10 in the periodic table …
For hydrogen: Protons = 1, Electron in first orbit = 1.
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instructions choose one element of the first 10 in the periodic table (…
For oxygen: Nucleus with 8 protons. First electron - orbit has 2 electrons, second electron - orbit has 6 electrons.
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answer the following questions. also indicate what resource you used to…
1) A heating/cooling graph of water has flat sections at 0°C (melting/freezing) and 100°C (boiling/condensing) with rising and falling temperature sections in between. Resources: …
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question 31 1 pts as the concentration of hydrogen ions increases, the …
Question 31: A. down; acidic Question 32: C. electrolytes Question 33: C. protons in its nucleus
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question 28 1 pts acids release hydrogen ions. have a ph above 7. take …
- Question 28: release hydrogen ions. - Question 29: called cations if they have a positive charge. - Question 30: synthesis reaction.
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step 3: write answers to the following questions. you must provide exam…
1. Solid: Molecules closely packed, vibrate in place (e.g., ice - cube). Liquid: Molecules close, can slide (e.g., water in a glass). Gas: Molecules far apart, move randomly (e.g.…
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question 25 1 pts for sodium to transform from a neutral atom to a posi…
- Question 25: C. lose an electron - Question 26: A. dissociates very little in solution - Question 27: A. number of protons in the nucleus
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question 22 1 pts an atom can be described as chemically inert if its o…
- Question 22: D. Both A and C are correct. - Question 23: B. eight protons. - Question 24: A. synthesis
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question 19 1 pts the most abundant element essential to life is carbon…
Question 19: B. oxygen Question 20: C. transfer of electrons from one atom to another Question 21: E. All of the above are correct
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question 16 1 pts the water molecule has two distinct ends, each with a…
Question 16: polar. Question 17: chemical bond. Question 18: element.
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question 13 1 pts chemical bonds formed by the sharing of electrons are…
- Question 13: B. covalent - Question 14: C. Protons and electrons - Question 15: B. hydrolysis
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question 7 1 pts hydrolysis ____ a water molecule. joins compounds by r…
Question 7: breaks down compounds by adding Question 8: covalent Question 9: Radon
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question 4 1 pts which type of chemical reaction results in the breakdo…
Question 4: decomposition reaction Question 5: Both A and C are correct Question 6: isotope
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question 1 1 pts atoms with fewer than eight electrons in the outer ene…
- Question 1: B. octet rule - Question 2: C. metabolism - Question 3: A. hydrolysis
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a chemist has 100 ml of a solution that is 8% acetic acid. if the chemi…
3.6%
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a. reactivity for non - metals (group 17) electronegativity decreases d…
1. As the number of protons increases across a period, the nuclear charge increases, pulling the electrons closer and decreasing the atomic radius. 2. Atoms with a smaller atomic …
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what is the structure of 1 - chloro - 3 - ethyl - 2 - heptanol? none of…
The structure with the chloro group on the first carbon, the - OH group on the second carbon, and the ethyl group on the third carbon of the 7 - carbon chain is the correct one. W…
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what product is formed when ch3ch2ch2ch2 - sh is oxidized? ch3ch2ch2ch …
$CH_3CH_2CH_2CH_2 - S - S - CH_2CH_2CH_2CH_3$ (the second option in the multiple - choice list)
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what is the iupac name of the compound below? ch3—ch2—c(ch3)(ch2ch3)—ch…
3,6 - diethyl - 3 - methyl - 8 - decanethiol
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what is the structure of 1 - chloro - 3 - ethyl - 2 - heptanol? none of…
(The first and third structures in the image are the same and are correct as they have the -OH at C - 2, -Cl at C - 1 and an ethyl group at C - 3. So the answer is the first/third…
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match the following periodic groups with their names. alkaline earth me…
Alkali Earth Metals - Group 2 Noble Gases - Group 18 Transition Metals - Groups 3 - 12 Halogens - Group 17 Alkali Metals - Group 1
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which statement concerning the compound shown below is incorrect? it is…
It can be oxidized to give a ketone.
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classify the following as either metals or non - metals by dragging the…
Metals: Sodium, Francium, Cobalt, Calcium Non - Metals: Oxygen, Phosphorus, Nitrogen, Chlorine, Argon
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which compound has the highest boiling point? ch3(ch2)4ch2oh ch3(ch2)2o…
$CH_3(CH_2)_4CH_2OH$
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use the periodic table. match each statement with the proper classifica…
sodium: Metals fluorine: Nonmetals contains many gases: Nonmetals conducts electricity in the solid state: Metals tends to lose electrons and form positive ions: Metals
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benzyl alcohol is a colorless liquid with a gentle, pleasant aroma. wha…
The structure with a carbon - oxygen double bond (C=O) where the carbon of the C=O is bonded to a hydrogen and the benzene ring (the fourth option from the top in the image which …
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question 8 (10 points) listen what is/are the carbonyl product(s) forme…
The third option (the structure with a ketone functional - group: $H_3C - C - C - CH_3$ with a carbon - oxygen double bond in the middle carbon).
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part i: balance the following equations by adding coefficients in the b…
1. Write un - balanced equation, count atoms of each element, adjust coefficients, verify final equation 2. 1 3. 1, 1, 1, 2 4. 111 5. 78 6. 32 7. 62
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what is the structure of 1,1,2 - trichloroethane? more than one of the …
First structure (the one with two Cl on one C and one Cl on the adjacent C of the two - carbon ethane chain)
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question 12 (10 points) listen what product is formed when ch3ch2ch2ch2…
$CH_3CH_2CH_2CH_2 - S - S - CH_2CH_2CH_2CH_3$
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question 13 (10 points) which is a secondary alcohol? h—o—c—o—h h h h h…
Question 13: D. $CH_3-\underset{OH}{\underset{|}{C}}-CH_2CH_2CH_3$ Question 14: Aldehyde
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question 14 (10 points) listen when a primary alcohol is oxidized, the …
B. aldehyde; carboxylic acid
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order the following in increasing atomic radius: o, li, c order the fol…
Increasing atomic radius: O, C, Li Increasing first ionization energy: Li, C, O
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n, f, li order the following in increasing electronegativity. na, f, c …
For N, F, Li: Li < N < F; For Na, F, C: Na < C < F
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what is the structure of 1 - chloro - 3 - ethyl - 2 - heptanol? none of…
We need to analyze the structures in the image one - by - one. Without seeing the actual correct structure among the options, we can't definitively choose. But if we had to follow…
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la pregunta 10 se refiere al siguiente pasaje. cuando se toca con una p…
# Explicación breve: La reacción descrita es una reacción de descomposición, ya que un compuesto (triyoduro de nitrógeno seco) se descompone en otros productos (explota y da una n…
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which is an example of an ether? none of these structures is an ether.
The fourth structure (the cyclic compound with an oxygen in the ring)
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the difference in between atoms determines whether a bond is polar or n…
electronegativity
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a chemist has an empty cylinder with a height of 30 cm and a cone - sha…
10 cm
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eq32: do the tube dilution, final dilution, and solve for v1 for each t…
For the first tube: $V_1 = 10\ mL$; For the second tube: $V_1 = 5\ mL$; For the third tube: $V_1 = 1\ mL$; For the fourth tube: $V_1 = 0.5\ mL$; For the fifth tube: $V_1 = 0.05\ m…
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eq 31: do the tube dilution, final dilution, and solve for v1 for each …
For the first tube: $V_1 = 20\ mL$ For the second tube: $V_1 = 2\ mL$ For the third tube: $V_1 = 0.2\ mL$ For the fourth tube: $V_1 = 0.02\ mL$ For the fifth tube: $V_1 = 0.002\ m…
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how did new weapons affect the fighting in world war i? check all that …
- Led to higher casualty rates - Made it a defensive war - Defenses against chemical weapons were required
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question 4 not yet answered points out of 1.00 p flag question the root…
d. weak acids
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3.47 identify each of the following changes of state as evaporation, bo…
a. Condensation b. Evaporation c. Boiling d. Condensation
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complete the sentences to explain the difference between atomic mass an…
Average atomic mass is a weighted average of all isotopes of an element, measured in atomic mass units (amu). Atomic mass unit is an extremely small unit not very useful to scient…
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complete this table to describe the three subatomic particles. location…
| Particle | Location | Charge | Mass | |--|--|--|--| | Proton ($p^+$) | In the nucleus | +1 | 1 amu | | Neutron ($n^0$) | In the nucleus | 0 | 1 amu | | Electron ($e^-$) | In the…
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3.43 identify each of the following changes of state as melting, freezi…
a. Melting b. Sublimation c. Freezing d. Deposition
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3.39 use the heat equation to calculate the energy for each of the foll…
a. $178.5\ cal$ b. $- 2615\ J$ c. $9.3\ kcal$ d. $10.78\ kJ$
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what molecules make up greenhouse gases? (select all that apply) oxygen…
B. carbon dioxide (CO2) C. nitrous oxide (N2O) D. methane (CH4)
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2. suppose you want to make the lemonade sweeter. describe how you woul…
You would add more sugar (solute) to make the lemonade sweeter. ### 3.
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3. describe the relationships between: a) motion of molecules and the k…
a) Faster - moving molecules have higher kinetic energy. b) Higher temperature means higher average kinetic energy of particles. c) Transfer of thermal energy can cause state - ch…
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1. theme patterns look at the recipe above. fill out the table to descr…
1. Solvent: Water; Solutes: Lemon - juice, sugar, flavorings (if any) 2. Add sugar (a solute) 3. See above plan for investigating the rate of salt dissolution in water by changing…
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what do these two changes have in common? baking cookies firing a clay …
B. Both are chemical changes. C. Both are caused by heating.
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what do these two changes have in common? rust forming on a metal gate …
Both are chemical changes.
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note: to answer some of the questions, it may help to reference a perio…
The isotope’s half - life is too long to be measured. The isotope does not emit a form of radiation.
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note: to answer some of the questions, it may help to reference a perio…
Strontium
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note: to answer some of the questions, it may help to reference a perio…
When excited electrons of an atom "fall" to ground state, they emit distinct lines of colored light.
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note: to answer some of the questions, it may help to reference a perio…
indigo on the visible light spectrum
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note: to answer some of the questions, it may help to reference a perio…
the distance between two crest points of a wave
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note: to answer some of the questions, it may help to reference a perio…
A. gamma rays
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4. directions select the correct answer. the diagram below represents a…
The portion of the left - hand diagram with the cluster of red dots (inside the dotted square) represents the salt before mixing.
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88. everyone has a total calorie \budget\ than can be split into ____ a…
88. Essential, extra 89. True 90. Carbon
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to prevent chemical contamination, a food handler should use only appro…
False
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a food handler does not need to follow the manufacturer’s directions an…
False
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what do these two changes have in common? water evaporating from a lake…
A. Both are only physical changes. C. Both are caused by heating.
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the production and use of plastic bags has an environmental impact. the…
Plastic bags are a low - cost way to transport goods. The process of making ethylene from fossil fuels releases carbon dioxide into Earth's atmosphere. Plastic bags can be dangero…
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you notice that the drain in your kitchen sink is clogged, although you…
You predict that your sink became clogged because substances dissolved in the water reacted to form a solid.
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which of these changes is a chemical change? water freezing glass break…
food digesting
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when ethylene is made, it reacts with other ethylene monomers to make p…
- Polyethylene is made of carbon and hydrogen. - Many ethylene molecules are joined together to form polyethylene. - HDPE is made of long side - by - side chains of polyethylene.
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which of these properties is a physical property of a compound? o tende…
melting temperature
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to make polyethylene, its monomer ethylene must first be synthesized fr…
High temperatures are required to make ethylene. The synthesis of ethylene is a chemical change.
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using the isotopic notation shown below and the periodic table, identif…
Isotopic Name: Krypton - 86 Symbol: $^{86}_{36}Kr$
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which tool in a chemistry laboratory is used to measure mass? o balance…
balance
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food and beverage containers are commonly made of tin, steel, aluminum,…
density
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you are told that a coin is made from solid gold. what questions, when …
What is the color of the coin? Can you score the side of the coin easily? (Is the coin soft and malleable?) What is the density of the coin?
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62. phytochemicals are essential nutrients. true false 63. high sources…
62. False 63. Packaged Cookies
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ethanol is a common laboratory solvent and has a density of 0.789 g/ml.…
$108.882$
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an experimental procedure you are conducting asks you to measure 90 ml …
100 mL graduated cylinder