化学
化学反应、化学计量、分子结构与元素性质。
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tag all the sp hybridized carbon atoms in this molecule. if there are n…
The two carbon atoms in the triple bond (\(C\equiv C\)) are sp - hybridized.
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name your business: kevs car detailing supplies what will you produce? …
No specific question is asked in a way that requires a single - word or short - answer response. However, if we consider the overall context, the main idea is about business plann…
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graded formative: unit 2 study guide part 1 a chlorine atom (cl) differ…
less electron
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graded formative: unit 2 study guide part 1 how do the masses of proton…
0
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read pages 54 - 55 in your textbook: 1. infer: what would happen if you…
Se llegará a átomos, que son la unidad más pequeña del elemento que mantiene sus propiedades químicas. 2. **Brief Explanations**: El término "átomo" proviene del griego "átomos", …
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graded formative: unit 2 study guide part 1 how do the masses of proton…
The mass of a proton and a neutron are approximately equal (about 1 amu each), while the mass of an electron is much smaller (about 1/1836 amu of a proton/neutron).
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matching: determine which scientist is associated with each of the foll…
1. J. J. Thomson 2. Niels Bohr 3. John Dalton 4. Ernest Rutherford 5. Erwin Schrödinger
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here is a graph of the pressure of boron trifluoride (bf₃) in a reactio…
Is $BF_3$ being created or destroyed by the chemical reaction? Destroyed If $BF_3$ is being created or destroyed, what is the rate at which it is being created or destroyed 1000 s…
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patterns of properties quick check which phrase describes ionization en…
energy required to remove an electron from an atom
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use the periodic table to answer the question. which change is likely t…
It will give up electrons, forming a positive ion.
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a chemical engineer is studying the rate of this reaction. 2cl₂o₅(g)→2c…
$t_{1/2}=0.80\ s$ $k = 0.87\ s^{-1}$ $[\text{Cl}_2\text{O}_5]=0.0012\ M$
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use the periodic table to answer the question. how many valence electro…
seven
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patterns of properties quick check 2 of 5 what are valence electrons? (…
the electrons in an atom's outermost energy level
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name your business: kevs car detailing supplies what will you produce? …
A possible challenge is high competition in the car - detailing supplies market. A potential solution is to invest in R&D for product differentiation.
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patterns of properties quick check which feature defines a neutral atom…
the number of electrons equal to the number of protons
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a chemical engineer is studying the rate of this reaction. nh₄oh(aq)→nh…
$t_{1/2}=20\ s$ $k = 0.035\ s^{-1}$ $[\text{NH}_4\text{OH}]=1.2\times 10^{-3}\ M$
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a chemical engineer is studying the rate of this reaction. 2h₃po₄(aq)→p…
$t_{1/2}=0.40s$ $k = 1.7s^{-1}$ $[H_3PO_4]=0.014M$
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name your business: kevs car detailing supplies what will you produce? …
Land: Factory site, storage land, distribution - center land Labor: Chemists, production workers, sales representatives Capital: Production machinery, distribution vehicles, R&D f…
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a chemistry graduate student is studying the rate of this reaction: 2h₃…
rate = $k[H_3PO_4]$ $k = 0.035\ s^{-1}$
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4. an substance. is a substance that cannot be chemically broken down i…
# Explicaciones detalladas: ## Paso 1: Definición de elementos Los elementos son sustancias químicas que no se pueden descomponer en sustancias más simples por métodos químicos no…
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which industry routinely looks for skilled workers with education or tr…
manufacturing industry
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1 multiple choice . select the best answer. (i) (5 points) the electron…
$1s^{2}2s^{2}2p^{5}$
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question 6 the article states: farmers needed fertilizer for their crop…
A. To describe the way farmers relied on guano because they could not just buy fertilizer
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question 5 what is a cause and effect relationship that takes place in …
D. Because chemical fertilizers were invented, guano fever died down after only a few years.
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question 2 think about the events below. according to the article, whic…
D. Russia was looking to sell Alaska for two cents an acre, and Seward was able to purchase it.
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a chemistry graduate student is studying the rate of this reaction: 2nh…
rate = $k[NH_3]$ $k = 0.049\ s^{-1}$
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read pages 52 - 53 in your textbook: 1. define: what is an element? 2. …
1. Un átomo es la partícula más pequeña de un elemento que conserva sus propiedades químicas. 2. 94 elementos se encuentran en la naturaleza. 3. Carbono, hidrógeno y oxígeno.
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a chemistry graduate student is studying the rate of this reaction: 2hi…
rate = $k[HI]^2$ $k = 42\ M^{-1}s^{-1}$
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question #3 multiple choice someone with a career in engineering, const…
manufacturing industry
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here is a graph of the pressure of sulfur dioxide (so₂) in a reaction v…
Is $SO_2$ being created or destroyed by the chemical reaction? Destroyed If $SO_2$ is being created or destroyed, what is the rate at which it is being created or destroyed 130 se…
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2h₃po₄(aq)→p₂o₅(aq)+3h₂o(aq) he fills a reaction vessel with h₃po₄ and …
$t_{1/2}=0.40\ s$ $k = 1.7\ s^{-1}$
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pregunta de opción múltiple cuando un líquido se calienta, pasa de líqu…
A. gas
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some measurements of the initial rate of a certain reaction are given i…
rate = $k[H_2][I_2]$ $k = 0.53\ M^{-1}s^{-1}$
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some measurements of the initial rate of a certain reaction are given i…
rate = $k[N_2]^2[H_2]$ $k = 270M^{-2}s^{-1}$
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some measurements of the initial rate of a certain reaction are given i…
rate = $k[N_2][H_2]^2$ k = $0.49M^{-2}s^{-1}$
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some measurements of the initial rate of a certain reaction are given i…
rate = $k[H_2][I_2]$ $k = 1.6\times 10^{5}M^{-1}s^{-1}$
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some measurements of the initial rate of a certain reaction are given i…
rate = $k[\ce{N2}][\ce{H2}]^{2}$ $k = 1.0\times 10^{4}M^{-2}s^{-1}$
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q3. most copper atoms (~70%) are cu - 63. based on the atomic mass list…
Cu - 65
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some measurements of the initial rate of a certain reaction are given i…
rate = $k[N_2]^2[H_2]^2$ k = $0.91M^{-3}s^{-1}$
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exam 2 fall 2025 your initials nt (ii) (5 points) which of the followin…
C - Cl (339 kJ/mol)
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a certain reaction is first order in h₂ and first order in i₂. use this…
$9.03$
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a certain reaction is second order in n₂ and first order in h₂. use thi…
Second row: $20.0\ M/s$ Third row: $6.25\ M/s$
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a certain reaction is second order in n₂ and first order in h₂. use thi…
| $[\text{N}_2]$ | $[\text{H}_2]$ | initial rate of reaction | | ---- | ---- | ---- | | $2.26\ M$ | $1.08\ M$ | $55.0\ M/s$ | | $2.26\ M$ | $0.396\ M$ | $20.0\ M/s$ | | $0.260\ M$…
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a certain reaction is first order in h₂ and first order in i₂. use this…
9.00 M/s 3.00 M/s
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a certain reaction is first order in h₂ and first order in i₂. use this…
| $[H_2]$ | $[I_2]$ | initial rate of reaction | | ---- | ---- | ---- | | $0.516\ M$ | $0.689\ M$ | $4.00\times 10^{-4}\ M/s$ | | $0.139\ M$ | $0.689\ M$ | $1.07\times 10^{-4}\ M/…
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a certain reaction is second order in n₂ and first order in h₂. use thi…
| $[N_2]$ | $[H_2]$ | initial rate of reaction | | ---- | ---- | ---- | | $2.43\ M$ | $1.02\ M$ | $0.0796\ M/s$ | | $2.43\ M$ | $1.74\ M$ | $0.138\ M/s$ | | $0.810\ M$ | $3.06\ M$…
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a certain reaction is first order in h₂ and first order in i₂. use this…
| $[H_2]$ | $[I_2]$ | initial rate of reaction | | ---- | ---- | ---- | | $1.44\ M$ | $2.31\ M$ | $6.00\times 10^{5}\ M/s$ | | $0.479\ M$ | $2.31\ M$ | $1.99\times 10^{5}\ M/s$ | …
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how did they expand the empire so quickly and effectively? life in trad…
C. "diplomacy and marriages were more common unifiers."
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q13. (7 points) (a) add the coefficients to balance the following chemi…
$72.9$ mol
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in a synthesis reaction, what happens? a. two or more substances combin…
A. Two or more substances combine to form a single compound.
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chapter 9 chapter review part a. vocabulary review match the terms in c…
1. b. homogeneous mixture 2. n. physical change 3. h. fog 4. c. heterogeneous mixture 5. a. element 6. m. law of conservation of mass 7. o. suspension 8. g. compound 9. l. coagula…
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stoichiometry is primarily used to = a. predict the speed of a chemical…
B. Calculate the amounts of reactants and products in a chemical reaction.
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which statement best describes an endothermic reaction? a. it releases …
D. It absorbs heat from the surroundings.
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use the table to answer the question. elements with their electronegati…
bromine and nitrogen
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covalent and ionic bonding quick check which phrase best describes elec…
the relative strength with which an element attracts electrons in a chemical bond
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the energy value listed for foods refers to the __________. a. total am…
B. amount of energy available as fuel for the body
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use the periodic table to answer the question. based on their locations…
nitrogen (N) and oxygen (O)
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q4. what is the formula mass (fm) for cobalt(iii) chlorate, co(clo3)3? …
B. 309.28 amu
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covalent and ionic bonding quick check which statement about sodium chl…
The sodium atom transfers electrons to the chlorine atoms to form ionic bonds.
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use the periodic table to answer the question. covalent and ionic bondi…
rubidium (Rb)
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given the following stanza, identify the rhyme scheme: \the cat sat on …
ABAB
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part a. vocabulary review match the terms in column i with the terms in…
1. b. homogeneous mixture 2. n. physical change 3. h. fog 4. c. heterogeneous mixture 5. a. element 6. m. law of conservation of mass 7. o. suspension 8. g. compound 9. l. coagula…
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q7. the number of moles of sulfur trioxide molecules in 155 grams is: a…
B. 1.94 moles
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9. main idea explain why evaporation of water is a physical change and …
531.95 g
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the amount of carbon in earths atmosphere can be observed by measuring …
Atmospheric CO₂ levels increased and decreased during roughly the same months each year.
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a common example of an endothermic reaction in the environment is the o…
melting
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the change in during a chemical reaction is denoted as δh.
enthalpy
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6- l’eau est-elle un atome? pourquoi?
Non, l'eau n'est pas un atome car elle est composée de molécules d'eau formées par des atomes d'hydrogène et d'oxygène.
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when salt or sugar dissolves in water, it undergoes an reaction, absorb…
Endothermic
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measures the heat absorbed or released during a chemical reaction.
Calorimeter
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objective: complete this pack of practice questions using your notes, t…
1. Ag 2. Approximately 200.59 3. Cl 4. Fe, Cu (among many others) 5. Kr 6. 11 7. He, Ne 8. F, Cl 9. W 10. Approximately 63.55 11. (Personal choice, e.g., H)
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cyanobacteria and small ______ caused oxygen levels to increase. the __…
1. plants 2. ozone 3. oceans 4. oceans 5. carbon - dioxide 6. similar 7. Aristotle 8. Earth 9. Circular motion 10. epicycles 11. backward 12. sun 13. speeds 14. Galileo 15. telesc…
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2- associez chacun des énoncés suivants à ce que disait dalton dans sa …
1. E 2. A 3. D 4. F 5. B 6. C
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which of the following are features of the nucleus of an atom? select a…
(a) The nucleus is located at the center of the atom. (b) It has relatively great mass compared to the other components of the atom. (c) The nucleus has a tiny size relative to th…
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3- identifiez les informations que lon retrouve dans le tableau périodi…
3 - Numéro atomique, symbole chimique, nom de l'élément, masse atomique. 4 - Le numéro atomique.
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which of the following are features of the nucleus of an atom? select a…
A. The nucleus is located at the center of the atom. B. It has relatively great mass compared to the other components of the atom. C. The nucleus has a tiny size relative to the t…
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in any atom, the size of the nucleus with respect to the size of the at…
C. Very small and dense and located in the center of the atom
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trends on the periodic table: 8. for calcium (ca) and barium (ba), expl…
Barium (Ba) has a larger atomic radius because it is lower in Group 2 of the periodic table than calcium (Ca), and atomic radius increases down a group due to the addition of elec…
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7. how many valence electrons are in the following element? a. f b. cl …
a. 7 b. 7 c. 7 d. 7 e. 6 f. 6 g. 6 h. 6
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7. how many valence electrons are in the following element? a. f b. cl …
a. 7 b. 7 c. 7 d. 7 e. 6 f. 6 g. 6 h. 6
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5. name an atom with the following characteristics. a. halogen b. nonme…
a. Chlorine (Cl) b. Oxygen (O) c. Sodium (Na) d. Silicon (Si) e. Cerium (Ce) f. Calcium (Ca) g. Iron (Fe) h. Helium (He)
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choose the correct answer. 6co₂ + 6h₂o → c₆h₁₂o₆ + 6o₂ in a chemical eq…
A. Reactant
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choose the correct answer. 6co₂ + 6h₂o → c₆h₁₂o₆ + 6o₂ in a chemical eq…
A. Product
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which particles constantly move around the center of an atom? a electro…
A. electrons
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3. what period are the following elements in? a. he b. ge c. rb d. i 4.…
3. a. He - Period 1; b. Ge - Period 4; c. Rb - Period 5; d. I - Period 5 4. a. Sulfur - Group 16; b. Ca - Group 2; c. Iodine - Group 17; d. Fe - Group 8
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which si unit of length is most commonly used to indicate the radius of…
C. 1 picometer (pm)
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helium is an example of a element b noble gas c p block element d metal…
E. a and b are correct
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which of the following statements is true about the atoms of any elemen…
A. All the atoms of a given element are identical in that they have the same number of protons.
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which statement is true about all the atoms of a given element? a they …
A. They all have the same number of protons.
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which formula would you use to calculate the heat absorbed by a 25 g sa…
1. B. $q = m\cdot c\cdot\Delta T$ 2. c) The amount of heat required to raise the temperature of one gram of the substance by one degree Celsius. 3. c) Water vapor turning into fro…
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4 multiple choice 1 point in a coffee - cup calorimeter, two substances…
4. b) The reaction is endothermic. 5. b) Exothermic, because energy is released by the water.
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6 multiple choice 1 point which of the following describes an exothermi…
6. B. Energy is released into the surroundings, causing the surroundings to feel warmer. 7. D. Energy is absorbed, and the process is endothermic.
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trends on the periodic table worksheet name 1. how is a group different…
1. Groups are vertical columns with elements having similar chemical properties due to the same number of valence electrons. Periods are horizontal rows where properties change gr…
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balancing act name laura taya atoms are not created or destroyed during…
$2Ca+O_2 ightarrow 2CaO$ $N_2 + 3H_2 ightarrow 2NH_3$ $2Cu_2O + C ightarrow 4Cu+CO_2$ $2H_2O_2 ightarrow 2H_2O + O_2$
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chapter 2 retake version 3 1) which atom has the smallest number of neu…
1. B. nitrogen - 14 2. D. argon - 40 3. D. 54, 54, 78 4. B. neutrons 5. D. is definitely a non - metal 6. B. definitely a metal 7. C. similar chemical properties only 8. A. metal,…
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chapter 2 recake version 3 1) which atom has the smallest number of neu…
1. B 2. (No question 2 in step - by - step, assume it's a skipped numbering) 3. (No question 3 in step - by - step, assume it's a skipped numbering) 4. B 5. C 6. B 7. E 8. A 9. C …
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13) calculate the percentage by mass of nitrogen in ptcl2(nh3)2. a) 4.6…
13. B. 9.34 14. D. 29.0 15. A. 23.63 16. B. $SOCl_2$ 17. A. $Na_2S_2O_3$ 18. B. $C_3H_3O$ 19. A. $C_3H_8O$ 20. A. $C_8H_8O_2$
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question 9 (1 point) is this a chemical or a physical change? letting t…
B. Chemical change
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the ______ is a narrow current of air that moves around the northern an…
1. Jet - stream 2. Dew - point 3. Wind 4. Pressure - gradient 5. Insolation 6. Heat - transfer 7. Weather 8. Heat - content 9. Thermal - energy 10. Temperature 11. Air - pressure …
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question 8 (1 point) is this a chemical or a physical change? cutting a…
b. Physical change