Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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question 18 of 23 the rate of a certain reaction was studied at various…
$E_a = 153\ kJ/mol$, $A = 2.4\times10^{15}\ s^{-1}$
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calculate the rate constant, k, for a reaction at 57.0 °c that has an a…
$1.61\times 10^{-2}$
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name: london coe period: 4th soluble or insoluble in water: cooking oil…
Solubility in water: Cooking oil - insoluble, Sugar - soluble, Soap - soluble, Dirt - insoluble, Salt - soluble. Solute - Solvent: Salt - water: Salt (solute), Water (solvent); Su…
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multiple choice 2 points which biogeochemical cycle does not include an…
A. Phosphorus
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complete the rhyme scheme. a a a b b april! april! are you here? oh, ho…
A, A, A, B, B
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complete the rhyme scheme. a b b b c we will never walk again slowly, w…
We will never walk again - A Slowly, we two, - B In spring when the park is sweet - B With midnight and with dew, - B And the passers - by are few. - B
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true or false. 1. a physical property of cobalt is that it is magnetic.…
1. True 2. False 3. False 4. True
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which elements did mendeleev change the atomic mass of to better match …
Be - Beryllium, In - Indium
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initial - rate data at a certain temperature is given in the table for …
$k = 8.75$, units: $s^{-1}$, $y=-30$
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11. the situation described in this passage was caused by 1. native ame…
11. 2. European settlement in North America 12. 3. forming alliances to fight the colonial settlers
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which statement names characteristics of a mineral? o it must be crysta…
It must be crystalline and have a definite chemical composition.
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5 what, if anything, is wrong with the nuclear equation shown below? (_…
The daughter product has the wrong atomic number.
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practice match the project with the proper chemistry discipline. match …
a. 5. analytical chemistry b. 1. biochemistry c. 4. physical chemistry d. 2. organic chemistry e. 3. inorganic chemistry
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day 2 label the properties below as with covalent bonds (cb) or ionic b…
low melting point: CB only nonmetals: CB soluble in water: IB (some ionic compounds are soluble) high melting point: IB bad conductors: CB shared electrons: CB low boiling point: …
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does the constitution need a \bill of rights\ to protect freedoms? fede…
The Federalists thought a Bill of Rights was unnecessary and dangerous, while the Anti - Federalists believed it was essential to protect citizens' rights from government overreac…
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select the correct answer. calcium carbonate is a compound that is used…
C. CaCO₃
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drag each statement to the correct location. classify the chemical equa…
Balanced: CaO + 3C → CaC₂ + CO, 2Mg + O₂ → 2MgO Not Balanced: Na + H₂O → 2NaOH + H₂, 4Fe + O₂ → 2Fe₂O₃
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select the correct number. iron reacts with oxygen to produce iron oxid…
3
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select the correct answer. sodium bicarbonate is the chemical name for …
C. There are three atoms of oxygen in sodium bicarbonate.
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select the correct answer. the picture represents sulfur trioxide. whic…
D. There is one atom of sulfur and three atoms of oxygen.
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14. identify each mixture as either homogenous or heterogenous. a. glas…
A. Homogeneous B. Homogeneous C. Heterogeneous D. Heterogeneous E. Heterogeneous F. Homogeneous G. Heterogeneous H. Heterogeneous
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the image shows a model of a lithium atom. the image shows subatomic pa…
4
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how many electrons does one neutrally charged atom of argon have? 18 58…
A. 18
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how many neutrons are there in 226ra? 226ra 88 314 226 138
D. 138
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which of the following represents a pair of isotopes? fe+2, fe+3 option…
Option 2. $^{12}C$, $^{14}C$
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1. use your knowledge of atomic calculations to complete the chart. ele…
| Element | Atomic Number | Atomic Mass | Protons | Neutrons | Electrons | | ---- | ---- | ---- | ---- | ---- | ---- | | Ne | 10 | 20 | 10 | 10 | 10 | | W | 74 | 184 | 74 | 110 | …
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13. what kind of changes do these words indicate? physical or chemical …
A. Physical B. Physical C. Physical D. Physical E. Physical F. Can be physical or chemical G. Chemical H. Chemical I. Chemical J. Chemical
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silicon is the second most abundant element in earth - crust. it is use…
28.1 amu
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exit ticket: lewis dot diagrams practice which of the following electro…
D. C with 4 dots around it
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exit ticket: lewis dot diagrams practice. which of the following elemen…
Se
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exit ticket: lewis dot diagrams practice which of the following electro…
The option with the symbol 'Ar' surrounded by 8 dots (2 on each of the four sides of the symbol) is correct.
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matter - properties and changes a liquid is a form of matter that flows…
1. Solid: A form of matter with definite shape and volume (e.g., wood, iron, paper). Liquid: A form of matter that flows, has constant volume, and takes the shape of its container…
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chem 100l - introduction to chemistry laboratory - experiment #5 data &…
0.1091 M
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multiple select question select all that apply what are recommended tip…
A. Organize the notes according to an outline or similar hierarchy. B. Arrange the notes to fit memory schemas you are already familiar with. C. Rework the notes and related mater…
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22. metal 23. chlorine 24. metalloid 25. transition elements 26. alkali…
22. g. loses electrons in bonding 23. c. a halogen 24. d. make good semiconductors 25. b. metals with unpredictable properties 26. g. loses electrons in bonding 27. f. has a full …
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74. what does a higher ph rating indicate about a shampoo? 75. which ty…
74. It indicates the shampoo is more alkaline. 75. Slightly more acidic. 76. Hair cuticle lifting, stripping of natural oils.
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task 3 - hydrolysis and dehydration synthesis video use any method to w…
34. To build larger molecules by removing water. 35. Oxygen atom. 36. Hydroxyl group. 37. To break down larger molecules by adding water. 38. Water and enzymes. 39. Dehydration sy…
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b. to be a painkiller since when cardiologists prescribed it to be a pr…
133. d. as a painkiller until cardiologists began prescribing it as a preventive 134. a. Whether they earn
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14 fill in the blank 1 point co --> answer answer answer answer answer …
carbon; mon-; oxygen; -ide
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13 fill in the blank 1 point n₂f₆ --> answer answer answer answer answe…
di - nitrogen hexa - fluoride
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11 fill in the blank 1 point n₂o₃ --> answer answer answer answer answe…
di, nitrogen, tri, oxygen, -ide
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water is a universal solvent because it... a freezes when it gets cold.…
B. dissolves more substances than anything else.
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10 fill in the blank 1 point ccl4 --> answer answer answer answer answe…
carbon, tetra-, chlor, -ide
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which of the following factors determines how harmful an introduced che…
d. all of the above
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9 fill in the blank 1 point nbr3 -> answer answer answer answer answer
nitrogen tribromide
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which sentence has a mistake in grammar or usage? * a. he shook the cru…
1. c. I see that Fred has wore his old shoes. 2. c. That fine circus elephant now belongs to my sister and I. 3. c. Gabriel and me will attend the geography bee.
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water is polar. what does that mean? a it is a molecule with no charge.…
D. It is a molecule with opposite charges on opposite ends
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4. read the following excerpt from the article \icebergs,\ which was po…
D. part of glacial ice
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6 fill in the blank 1 point h₂o --> answer answer answer answer answer …
dihydrogen;oxide;hidrogen;ox;di -
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fill in the blank 12 points match the chemical name with the appropriat…
1. $CF_4$ 2. $N_2S_3$ 3. $PN$ 4. $SiBr_4$ 5. $ICl_3$
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match the chemical name with the appropriate chemical formula 1 carbon …
1. Carbon tetrafluoride - $CF_4$ 2. Dinitrogen trisulfide - $N_2S_3$ 3. Phosphorus mononitride - $PN$ 4. Silicon tetrabromide - $SiBr_4$ 5. Iodine trichloride - $ICl_3$ 6. Disulfu…
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3 fill in the blank 1 point c₇o₃ --> hepta- × carbon × tri- × ox × tri-…
hepta - carbon tri - oxide
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1. write a balanced equation for each nuclear change. a. carbon - 14 em…
a. $_{6}^{14}C ightarrow_{2}^{4}He+_{4}^{10}Be$ b. $_{1}^{2}H+_{1}^{3}H ightarrow_{2}^{4}He+_{0}^{1}n$ c. $_{6}^{14}C ightarrow_{-1}^{0}e + _{7}^{14}N$ d. $_{7}^{14}N+_{2}^{4}He i…
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fill in the blank question movement of molecules across the capillary w…
Filtration
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1 fill in the blank 1 point sci2 --> sulfur - di - chlor - ide sulfur -…
sulfur dichloride
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multiple choice question what process, that occurs in capillaries, is d…
D. Filtration
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fill in the blank 1 point cl4 --> answer answer answer answer answer cl…
carbon
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name: name redacted mod: 3b date: abc 3: ionic bonding activity (binary…
# Explanation: ## Step1: Identify metal and non - metal for Na + F Na (sodium) is a metal, F (fluorine) is a non - metal. ## Step2: Determine valence electrons Na has 1 valence el…
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match the chemical name with the appropriate chemical formula 1 carbon …
1. $CF_4$ 2. $N_2S_3$ 3. $PN$ 4. $SiBr_4$
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match the chemical name with the appropriate chemical formula 1 carbon …
1. $CF_4$ 2. $N_2S_3$ 3. PN 4. $SiBr_4$
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reinforcement use the words listed below to correctly complete the conc…
Left branch (from top to bottom): pure substances; atoms (same); gold, iron; atoms (different); salt, water Right branch (from top to bottom): mixtures; solutions; vinegar, soft d…
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2. suppose that you did a procedure similar to this lab but using a sam…
a. $1.34\ g$ b. $0.0228\ mol$ c. $2.43\ g$ d. $0.0686\ mol$ e. $NiCl_3$
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5. the number of protons in an atom equals the atomic number. 6. the ve…
5. Atomic number 6. Groups or families 7. 8 protons and 8 electrons 8. B. Halogens 9. C. Noble gases 10. A. Alkali metals 11. B. Halogens 12. D. Alkaline earth
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3. which element is a metalloid? a) carbon b) silicon c) calcium d) neo…
4. B. Silicon 5. B. O₂ 6. groups 7. 8 8. B. Halogens 9. C. Noble gases 10. A. Alkali metals 11. B. Halogens 12. D. Alkaline earth
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how many electrons are able to be in the second shell (layer) of an ato…
C. 8
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pre - lab questions answer questions 1 and 2 after you have read the ex…
a. $C_4H_5N_2O$ b. Molar mass: $194.22\ g/mol$, Percent composition: C: $\approx49.47\%$, H: $\approx5.20\%$, N: $\approx28.86\%$, O: $\approx16.48\%$ c. $\approx0.243\ g$ d. $\ap…
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based on the periodic table, how many protons are found in an atom of i…
26 (corresponding to the second option in the multiple - choice list)
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how do you find atomic (molecular) mass? by adding the number of proton…
By adding the number of protons and neutrons in the nucleus
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an atomic model for an element is shown below. based on the model, whic…
It is a lithium atom because it has 3 protons and 3 electrons.
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14. jerusha and anavi are working very hard to tend their organic veggi…
$\frac{40}{27}\text{ m/s}^2\approx1.48\text{ m/s}^2$
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how many valence electrons does a neutral atom of beryllium (be) have? …
A. 2
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h₂o --> answer answer answer answer answer penta- mon- di- tetra- chlor…
dihydrogen oxide
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true/false – physical vs chemical changes 1) when ice melts into liquid…
1. True 2. True 3. False 4. False 5. False 6. True Riddles: 1. Water 2. Rust 3. Salt (or other soluble substance that doesn't react chemically with water) 4. Carbon dioxide 5. Ele…
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based on its electron configuration, which element will most likely gai…
C. Iodine (I)
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if an atom has nine protons and ten electrons, then the atom is positiv…
negatively charged.
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which element is most likely to form an ion with a negative 2 charge? o…
Oxygen
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when a neutral atom gains or loses electrons, it becomes more stable. a…
an ion.
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what change has taken place in the following? k → k⁺ loss of a proton g…
loss of an electron
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the diagram below is the bohr model of an atom. which best describes th…
It has 6 electrons.
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5 fill in the blank 1 point p₂o₅ -> answer answer di- × pent- × answer …
diphosphorus; pentoxide
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chlorine (cl) is found in group 17 (7a) of the periodic table. chlorine…
A. gain one electron
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what best represents how electrons are arranged in the energy levels of…
first energy level - 2 electrons, second energy level - 4 electrons
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finally, answer the questions below: 2. __________ is the chemical resp…
2. Capsaicin; Scoville Scale 3. Capsaicin binds to TRPV1 receptors which are also activated by heat, tricking the body into sensing heat. 4. Carolina Reaper 5. Capsaicin has antib…
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a chemist mixed x liters of a 2% saline solution with y liters of a 6% …
# Explicación: ## Paso 1: Encontrar la cantidad de sal en cada solución La cantidad de sal en la solución del 2% es $0.02x$ (ya que el 2% se escribe como 0.02 y se multiplica por …
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if an atom has five protons and four electrons, the atom is neutral. ra…
D. positively charged
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use the information in the table to answer the question that follows. a…
They are isotopes of the same element.
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an atom of the element fluorine can be represented by the bohr model sh…
10
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analysis - worksheet page 3: part ii. economic considerations 1. based …
a. The cost to make 1000 grams of aspirin is $55.32. b. Yes, we can beat the supplier's price. c. (No solution provided as it is an optional bonus and no reaction formula is given…
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multiple choice - counting atoms & elements 1) water is a substance tha…
1. B. 2 hydrogen, 1 oxygen 2. A. Sodium and Chlorine 3. B. 2 4. A. 6 5. B. $NaCl$ 6. C. 3
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5) chemical changes questions 6) name 5 elements - symbols 7) name 2 co…
6) Hydrogen (H), Oxygen (O), Carbon (C), Nitrogen (N), Sodium (Na) 7) Water (H₂O), Carbon dioxide (CO₂) 8) A form of matter with definite composition and distinct properties. 9) H…
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complete this sentence correctly: most energy comes from heat energy an…
For the first question: the sun and is converted to food energy For the second question: is decreased
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true/false indicate whether the statement is true or false. 29. the num…
29. True 30. True 31. True 32. True 33. False 34. False 35. False
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23. which of the following is classified as an inorganic compound: a. w…
23. a. water 24. a. play a role in nerve impulse transmissions and muscle contractions 25. b. protons in the atomic nucleus 26. a. $NaCl$ 27. d. 14 28. c. a triglyceride
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read the following description of a data set. fair - view college has a…
$13$
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7. which of the following leads to an increase in the rate of a chemica…
7. e. increased temperature 8. e. 6 9. a. neutrons; atomic masses 10. e. ATP is a modified nucleotide with three phosphate groups, ribose, and adenine
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identify the choice that best completes the statement or answers the qu…
1. a. cation 2. c. proteins 3. c. surface tension 4. e. is neutral 5. d. base 6. b. cation
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multiple choice identify the choice that best completes the statement o…
1. a. cation 2. c. proteins 3. c. surface tension 4. e. is neutral 5. d. base 6. b. cation
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atomic structure & isotope worksheet 1. the mass of an atom is containe…
1. protons; neutrons 2. protons 3. protons 4. difference between protons and electrons 5. c) nucleus 6. d) ion 7. b) neutral atom 8. b) different number of neutrons 9. c) carbon -…
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which of the following electron dot notations is correct for the elemen…
The option with 8 dots evenly placed around the 'Ar' symbol (the second and fourth options in the image seem to be the same correct one with 8 dots around 'Ar') is correct.
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what do these two things have in common? • roasting a marshmallow over …
B. Both are chemical changes