化學
化學反應、化學計量、分子結構與元素性質。
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mrs. buckley made an omelet. in a pan, she mixed three 50-gram eggs wit…
There was some water in the eggs, milk, and cheese. When the omelet cooked, the water vaporized. Then, it condensed on the pan's lid.
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1) bridget mixed soy sauce, rice vinegar, and sesame oil together in a …
The mass of the sesame oil is 50 grams, so the bar for sesame oil in the graph should be drawn to represent 50 grams.
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what do these two changes have in common? bleaching hair using polish t…
B. Both are chemical changes.
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what do these two changes have in common? baking cookies deep - frying …
B. Both are chemical changes, C. Both are caused by heating (assuming the options are labeled as A: Both are only physical changes, B: Both are chemical changes, C: Both are cause…
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what do these two changes have in common? sauce burning on a stove a pi…
Both are chemical changes.
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1 select the correct answer. which statement about herbal health produc…
C. Natural products might have negative side effects.
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what do these two changes have in common? picking up a paper clip with …
A. Both are only physical changes.
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what do these two changes have in common? knitting yarn into a scarf ic…
A. Both are only physical changes
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satire in swifts \a modest proposal\ disobliging england. for this kind…
B. He insists that he cannot benefit personally from his proposal.
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2 select the correct answer. how does regular exercise help make us mor…
D. We breathe in more oxygen while exercising, which helps us feel more awake.
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7. what is the lewis dot structure for f? options (lewis dot structures…
The second option (the one with .$\ddot{\text{F}}\colon$? Wait, no, the options: first is .$\dot{\text{F}}\cdot$, second is .$\ddot{\text{F}}\colon$? Wait, maybe the second option…
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3. what is the lewis dot structure for an element in group 2? options (…
The first option (•X•) ### Question 4:
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question 14 (1 point) saved hydrogen is the lightest of elements with a…
4.3 (corresponding to the option with 4.3, e.g., the option labeled 4.3 in the multiple - choice list)
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question 15 (1 point) saved what is the correct equilibrium constant ex…
A. \( K_{\text{eq}} = \frac{[\text{N}_2][\text{Cl}_2]^3}{[\text{NCl}_3]^2} \)
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Question was provided via image upload.
\( X^\bullet \) (the first option with one dot around \( X \))
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question 15 (1 point) saved what is the correct equilibrium constant ex…
\( K_{eq} = \frac{[N_2][Cl_2]^3}{[NCl_3]^2} \) (the first option: \( K_{\text{eq}} = \frac{[\text{N}_2][\text{Cl}_2]^3}{[\text{NCl}_3]^2} \))
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question 15 (1 point) saved what is the correct equilibrium constant ex…
\( K_{eq} = \frac{[N_2][Cl_2]^3}{[NCl_3]^2} \) (the first option: \( K_{\text{eq}} = \frac{[\text{N}_2][\text{Cl}_2]^3}{[\text{NCl}_3]^2} \))
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8. which of these is a correct lewis structure for carbonate ion (co₃²⁻…
The third option (the one with \( [:\overset{..}{\text{O}}-\text{C}=\overset{..}{\text{O}} \atop \quad \quad :\overset{..}{\text{O}}:]^{2-} \))
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7. what is the lewis dot structure for an element that will form an ion…
\(\bullet X^\bullet\) (the second option)
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use the following information to answer the next question. carbon monox…
D. 0.42, 2.3 mol
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6. what is the lewis dot structure for strontium? options (lewis dot st…
A. • Sr • (assuming the first option is labeled A; if not, the option with two dots, one on each side of Sr)
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question 17 (1 point) saved use the following information to answer the…
4.5 (the option with 4.5, e.g., if options are labeled as E. 4.5, then E. 4.5)
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question 17 (1 point) saved use the following information to answer the…
4.0
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which statement primarily appeals to logos to support the position that…
La tercera declaración: "While it is true that electives may not be explicitly academic, in reality, electives can still help students develop valuable skills, such as critical th…
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question 18 (1 point) saved a very large value of $k_{eq}$ indicates th…
the reaction makes a lot of product
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the equilibrium constant has been determined in several reactions as fo…
2, 3, 4, 1 (i.e., the option with "2, 3, 4, 1")
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question 7 (1 point) saved when pressure i and volume ii the reaction i…
A. decreases, increases, more
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study paths tx math bridge - stage 1 unit test: measurement measurement…
150°C
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tx math bridge - stage 1 unit test: measurement measurement question id…
Water freezes at 0°C or 32°F. Water boils at 100°C or 212°F.
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which of the following forms of alcohol can be consumed? a. propanol b.…
D. ethanol
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on a distant planet, the fractional abundance of helium is given in the…
\(3.6011\) (amu)
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which of the following ailments could be health effects from inhaling f…
- Dizziness (checked) - Nausea (checked) - Cancer (checked) - Stomach ulcers (checked) - Kidney damage (checked)
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1) in 1964, stephanie kwolek and her team at dupont, a chemical company…
1. Problem (related to producing Kevlar from murky solution) - Kwolek used a laboratory spinneret. 2. Problem (related to helping students understand) - Kwolek developed the nylon…
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questions 43 - 47 prompt questions 43 - 47: pick the correct definition…
- Reaction between a hydrocarbon and oxygen. - Reaction where a gas is formed. - Reaction where electrons are transferred.
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in 1986, the worlds worst nuclear power plant accident occurred at cher…
- Problem (Chemical explosion/fire): Solution - A crew poured sand on the reactor. - Problem (Rainwater explosion risk): Solution - A crew built a concrete structure to seal the r…
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questions 28 - 31 prompt questions 28 - 31: complete the tables by fill…
- # protons: 25 - # neutrons: 30 - # electrons: 23
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questions 28 - 31 prompt questions 28 - 31: complete the tables by fill…
- # protons: 29 - # neutrons: 35 - # electrons: 28
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questions 28 - 31 prompt questions 28 - 31: complete the tables by fill…
# protons: 27 # neutrons: 33 # electrons: 24
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27 formula 4 points a 2.71 cm × 2.71 cm × 2.71 cm cube has a mass of 37…
\( 1.90 \, \text{g/cm}^3 \)
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if you work on this course in a classroom or computer lab, ask the inst…
Natural Science (subfield could be Chemistry or a lab - related science within Natural Science)
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1. for each compound below, write in the missing formula or name. | nam…
| Name | Formula | Name | Formula | | --- | --- | --- | --- | | vanadium (II) sulfide | \( \text{VS} \) | zirconium (IV) sulfide | \( \text{ZrS}_2 \) | | ruthenium (III) sulfide |…
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question 42 (2 points) instructions: answer all of the following questi…
The pH of the methanoic acid solution is approximately $\boldsymbol{2.10}$. ### 2) Solution for HCl Concentration (Magnesium Hydroxide Neutralization)
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4 a student correctly identifies fecl₂ and fecl₃ as ionic compounds but…
A. Iron can form more than one oxidation state, which must be indicated in the name.
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question 42 (2 points) instructions: answer all of the following questi…
\(2.10\) ### Sub - question 2
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which of the following is the correct nomenclature for $\\ce{al_{2}o_{3…
A. Aluminum Oxide
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exit ticket - what is an example of an acid? what was the ph? - what is…
- Example of an acid: Hydrochloric acid (HCl), pH ~1 - 3 (varies by concentration). - Example of a base: Sodium hydroxide (NaOH), pH ~11 - 14 (varies by concentration). - Basic: p…
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using the concept of electrostatic force, predict which of the followin…
$\ce{Na3P}$ has the highest lattice energy. Justification: Lattice energy depends on ion charge magnitude (product) and ionic radius. $\ce{Na3P}$ has $\ce{Na^+}$ and $\ce{P^{3-}}$…
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match each item to the correct statement below. the ionization constant…
- the ionization constant of water: 5. \( K_w \) - a hydroxide ion: 3. \( \text{OH}^- \) - a hydronium ion: 4. \( \text{H}_3\text{O}^+ \) - the negative common logarithm of the co…
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a. balance the following equations. 1. ______ na + ______o₂ → ______na₂o
4, 1, 2 (coefficients for Na, $O_2$, $Na_2O$ respectively)
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4. a 1.00 l sample of hcl(aq) is prepared and has a ph of 1.045. what m…
The mass of \(HCl(g)\) dissolved is approximately \(\boldsymbol{3.29\space g}\) (or more precisely, depending on significant figures, around 3.3 g or as calculated with more preci…
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11. explain why higher-frequency waves on the em spectrum (like x-rays …
Higher - frequency EM waves (e.g., X - rays, gamma rays) have higher energy ($E = hf$, $h$ = Planck's constant, $f$ = frequency). This high energy can ionize atoms/molecules, dama…
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____ n₂ + ____ h₂ → ____ nh₃ ____ al(oh)₃ + ____ hbr → ____ albr₃ + ___…
First equation: $\boldsymbol{1}\ce{N_{2} + 3H_{2} -> 2NH_{3}}$ Second equation: $\boldsymbol{1}\ce{Al(OH)_{3} + 3HBr -> 1AlBr_{3} + 3H_{2}O}$
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______h₃po₄ + ______koh → ______k₃po₄ + ______h₂o ______k + ______b₂o₃ …
1. $\boldsymbol{1}\ce{H3PO4 + 3KOH -> 1K3PO4 + 3H2O}$ 2. $\boldsymbol{6}\ce{K + 1B2O3 -> 3K2O + 2B}$ 3. $\boldsymbol{1}\ce{HCl + 1NaOH -> 1NaCl + 1H2O}$ 4. $\boldsymbol{10}\ce{Na …
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select all the correct answers. groundwater deposits are under threat o…
- recycling groundwater for reuse - regulating the amount of groundwater used to water neighborhood lawns - monitoring the chemicals used and released during fossil fuel extraction
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directions: answer each question completely. indicate how you determine…
s: 1) a. Barium Iodide b. Aluminum Sulfide c. Calcium Oxide 2) a. Magnesium Nitrate b. Strontium Sulfate c. Lithium Phosphate
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tdsb.elearningontario.ca question 11 (1 point) the variable, ( q_{eq} )…
the reaction quotient using concentration ### Question 12
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read the poem. skimming the bottom in the company of toes, i observe th…
C. abcb
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read this excerpt from \sea fever\ by john masefield. and the wheels ki…
C. The fixed meter and predictable rhyme scheme create an upbeat rhythm.
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in two to four sentences, write an analysis explaining how john masefie…
John Masefield's "Sea Fever" uses iambic tetrameter (four iambs per line) and an AABB rhyme scheme (e.g., "sea"/"me", "sky"/"by" in the first stanza). This creates a rhythmic, rep…
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problem: first ionization energy describes the amount of energy needed …
Sodium's electron configuration is \(1s^2 2s^2 2p^6 3s^1\). The first ionization energy removes the \(3s^1\) electron (easy, small energy). The second removes an electron from the…
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11. define ionic bond. 12. what is the charge on an ionic compound? 13.…
An ionic bond is the electrostatic attraction between positively - charged cations and negatively - charged anions, formed by electron transfer between a metal and a non - metal a…
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ionic bonds 11. define lonic bond. 12. what is the charge on an ionic c…
(for question 11): An ionic bond is a chemical bond formed by the electrostatic attraction between oppositely - charged ions, usually formed when a metal transfers electrons to a …
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Question was provided via image upload.
1. valence shell; 8 2. different 3. a. A chemical formula uses element symbols and subscripts to represent the ratio of atoms in a compound. b. A subscript in a chemical formula i…
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the work must of your highest quality. assessment therefore you need to…
\((x - 1)(x - 6)\) ### Part (b) - Length and Width when \(x = 14\) m
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read the poem. skimming the bottom in the company of toes, i observe th…
The option with "abab" (e.g., if the options are labeled as: - aabb - abab - abcd - abab Then the answer is the option with "abab" (e.g., B. abab or D. abab, depending on numberin…
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2. properties of compounds are the same/different from the properties o…
different ### Question 3a
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1. an atom is most stable when it’s ____________ (outer energy level) i…
First blank: valence shell; Second blank: 8
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read this excerpt from \sea fever\ by john masefield. and the wheels ki…
C. The fixed meter and predictable rhyme scheme create an upbeat rhythm.
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question 5 1 pts based on the image in figure 3, which of the following…
Molecule
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in todays video, the teacher told us about the law of conservation of m…
175 g of mixture
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a chemical called polypropylene makes up many of the most common plasti…
C. crude oil
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13 drew learned that glass is made from sand. he found a pile of sand, …
D. Making glass from sand requires a chemical reaction.
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aspirin is a medication used to reduce pain, fever, and inflammation. p…
C. Aspirin is a synthetic material.
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9 vinblastine is a medicine that is used to treat certain kinds of canc…
D. looking for ways to produce vinblastine from other resources
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7 directions: select each correct answer. more than one answer may be c…
water, plants
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synthetic fibers, like plastic, are derived from organic compounds. the…
D. The longer lasting material is more difficult to break down
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directions: select each correct answer. more than one answer may be cor…
B. atmospheric nitrogen, C. natural gas
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which of the following best describes surface mining? removing the eart…
A. removing the Earth's surface to extract resources
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polyester is a synthetic material used for many different purposes. it …
D. Producing certain synthetic materials could have a greater environmental impact than disposing of them.
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the diagram below represents a process through which glucose found in p…
B. It is a synthetic material
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which multimedia choice would be most effective in persuading blog read…
A. a video clip featuring the unhealthy ingredients in fast food
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34. what is the main function of biogeochemical cycles? reduce carbon d…
B. recycle elements through Earth's systems (assuming the second option is labeled B; if the selected option in the image is the second one, the answer is the option with "recycle…
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2) identify the following as a physical or chemical property a) the col…
### Question 2 (Identifying Properties) #### Part a) # Explanation: ## Step1: Recall property types Physical properties are observable without changing substance identity (e.g., c…
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2) identify the following as a physical or chemical property a) the col…
physical property ### Problem 2b:
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name: teacher: date: q2 chemistry: u4l8 intro to covalent bonding prewo…
## You Try: PCl₅ 1. First element name: \(\boldsymbol{\text{Phosphorus}}\) 2. 5 chlorine atoms = prefix \(\boldsymbol{\text{penta-}}\) & change chlorine to \(\boldsymbol{\text{chl…
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choose the best answers. 1. john is an electrician working on a high-vo…
B. insulators ### Second Question (Metal in Car)
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what term describes human - caused changes to the environment? a. organ…
c. Anthropogenic ### Second Question (Which practice involves removing natural resources from the Earth?)
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date: prepwork part 1: melting point oer practice 1. which of the follo…
C. BeS ### Question 2
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translate to spanish: how is your chemistry class? ¿cómo es tu clase de…
B. ¿Cómo es tu clase de química?
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the table below shows the amount of grams of iodine-125 left after seve…
\( 0.98 \)
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what is the name for an ion with a negative charge? anion cation union …
A. anion
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how is coal formed? marine organisms are accumulated in underwater sedi…
C. Ancient plant remains are compressed and heated over millions of years.
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the octet rules states that most elements want to have ______ valence e…
8 (corresponding to the option with the number 8)
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38/50 which one of the following is an example of a base? lemons orange…
C. dish soap (assuming options are labeled A: lemons, B: orange juice, C: dish soap, D: vinegar)
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a student works with a new substance. he concludes it conducts electric…
A. Metal
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which solution will change red litmus paper to blue? a. hcl because it …
D. NaOH because it gives off $\ce{OH^-}$ ions
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36/50 bleach and oven cleaner are: weak bases weak acids strong acids s…
D. strong bases (assuming the options are labeled A: weak bases, B: weak acids, C: strong acids, D: strong bases)
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metals are on what side of the periodic table? right side left side sta…
B. Left side (assuming the options are labeled A. Right Side, B. Left side, C. Stairstep)
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what type of reaction is the following: 2ki -> 2k + i₂ options: decompo…
Decomposition (the option labeled "Decomposition" among the choices)
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1 multiple choice 1 point a homogeneous mixture was formed consisting o…
B. ethanol ### Question 2