化學
化學反應、化學計量、分子結構與元素性質。
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33. which container(s) represents an element? 34. which container(s) re…
33. C 34. A 35. A, B, D, F 36. D 37. B 38. None of the above shown
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32. classify the following changes in matter as a physical change or a …
Hammering metal into sheets: Physical change Rusting: Chemical change Rotting wood: Chemical change Heated water changes to steam: Physical change Melting Ice: Physical change Sal…
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section #5: properties and changes in matter 31. classify the following…
| Property | Physical or Chemical? | Intensive or Extensive? | |--|--|--| | Density | Physical | Intensive | | Tendency to Rust | Chemical | N/A (not applicable for chemical prope…
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section #4: mixtures & separating mixtures (s) - solid, (l) - liquid, (…
21. solution 22. filtration 23. b. boiling point 24. c. a definite composition 25. d. NaCl(aq) 26. a. air 27. b. mixture 28. (Particle diagram with uncombined A and B atoms) 29. b…
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identify the technique you would use to separate each mixture. 33. two …
Filtration
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understanding main ideas identify each property as either physical or c…
14. Physical, Intensive 15. Chemical 16. Physical, Intensive 17. Physical, Intensive 18. Physical, Extensive 19. Chemical 20. Physical, Intensive 21. Physical, Intensive 22. d. st…
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report sheet name asha partners name lily tran date section 43 instruct…
- Mass of $NaOH$ for 250 mL of 0.03 M solution: $0.3\ g$ - Volume of $HCl$ for titration (using $M_{HCl}=0.03403\ M$ and $V_{NaOH} = 10\ mL$): $8.8\ mL$ - Concentration of $NaOH$ …
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identify each mixture as either homogeneous or heterogeneous. 35. stain…
35. homogeneous 36. heterogeneous 37. homogeneous 38. heterogeneous 39. heterogeneous 40. heterogeneous 41. heterogeneous 42. homogeneous 43. homogeneous 44. c. element 45. b. com…
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match the definition in column a with the term in column b. column a 1.…
1. f. solution 2. d. law of conservation of mass 3. e. law of definite proportions 4. a. law of multiple proportions 5. c. periodic table 6. b. percent by mass 7. i. states of mat…
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a 25.0 g sample of magnesium oxide (mgo) contains 10.8 g of magnesium. …
D. 56.8%
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samples of gases containing nitrogen and oxygen were decomposed by elec…
D. $NO_2$
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partners name_ivy tran instructor_dr. jia goal molarity of the naoh sol…
The mass of $NaOH$ needed is $0.50\ g$. For the dilute $HCl$ ($0.008226\ M$), the volume of $HCl$ needed is approximately $1.52\ L$. For the concentrated $HCl$ ($0.03403\ M$), the…
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distinguish between an element and a compound. 250 words remaining
An element consists of one - type atoms and is indivisible chemically. A compound is formed by chemical combination of different elements in a fixed ratio and has distinct propert…
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during an analysis, several samples of a hydrocarbon compound are burne…
The law of definite proportions. The percentage composition of carbon and hydrogen in the hydrocarbon is constant across different - mass samples, which is in accordance with the …
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if 14 atoms of carbon react with 28 atoms of oxygen to form carbon diox…
A. 42
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how many individual atoms are present in one unit of sodium sulfate, na…
A. 7
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a 1 g sample of the compound hydrogen chloride was analyzed and found t…
C. 2.7%
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which statement is true? a) the smallest particle that makes up an elem…
B. Pure compounds have the same composition regardless of where they are found or how they are made.
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la concentration en matières grasses indiquée sur un contenant de lait …
a) Environ 461,54 mL b) Environ 61,54 mL
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act. 10 word\tsynonym or antonym resource\tinformation plan draft revie…
plan - scheme draft - outline revise - modify edit - modify several - numerous dialogue - conversation abandoned - occupied narrative - story
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les concentrations de deux solutions ayant les mêmes constituants sont …
La solution avec une concentration de $15\ \% m/V$ est plus concentrée.
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all of the following are good networking ideas except joining a busines…
- First question: Creating a pyramid - type sales scheme with agents real estate lawyers and bankers - Second question: Your inspection report
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7.90g h₃po₄ →? mol 3.7 molecules →? mol
The number of moles of 7.90 g H₃PO₄ is approximately 0.0806 mol, and the number of moles of 3.7 molecules is approximately $6.14\times10^{-24}$ mol.
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6. how do pollutants typically affect marine food webs? a) they improve…
6. b) They accumulate in the tissues of organisms 7. a) Ocean warming 8. d) To break down dead organic matter and recycle nutrients 9. c) Overpopulation of sprat and herring 10. b…
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on prépare une solution aqueuse déthanol. or, léthanol se présente sous…
a) Ajoutez $157.5\ ml$ d'éthanol et complétez avec de l'eau pour obtenir $450\ ml$ de solution. b) Ajoutez $81\ ml$ d'éthanol et complétez avec de l'eau pour obtenir $450\ ml$ de …
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on dissout de liode dans de lammoniac pour préparer 4,5 l dune solution…
a) $16,2\ g$ b) $675\ g$
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on a préparé 720 ml dune solution désinfectante en dissolvant 145 g dét…
a) 21.3% b) 20.1%
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on a préparé 250 ml dune solution en dissolvant 23.5 g de soluté. calcu…
a) 94 g/L b) 9.4 %
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make observations about how the different body systems work in the meta…
One would observe the breakdown of starch into glucose in the digestive system and its subsequent absorption into the bloodstream.
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7 le sirop dérable est fabriqué à partir deau dérable, une solution aqu…
Lorsque l'eau d'érable bout, l'eau s'évapore tandis que le sucre reste, augmentant ainsi la concentration de sucre dans la solution restante.
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6 exprime chacune des concentrations suivantes en grammes par litre (g/…
a) 153 g/L b) 10 g/L c) 295 g/L
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5 exprime chacune des concentrations suivantes en pourcentage masse/vol…
a) 2,13% b) 0,045% c) 43,57%
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4 dans chaque cas, indique la meilleure façon dexprimer la concentratio…
a) % m/V b) % m/m c) % V/V
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3 sur une bouteille dalcool isopropylique, on peut lire linformation ci…
a) 100, 30 b) 1) 60 ml 2) 50 ml
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2 lillustration ci - contre montre ce que martine a obtenu après avoir …
Non, elle n'a pas raison. L'huile et l'eau ne forment pas une solution car elles sont immiscibles.
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try again! answer two in a row correctly to continue. click to fix any …
After Oliver Oken tried the experiment himself, he found a mistake in the other chemists' results.
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1 indique si chacun des énoncés est vrai ou faux. sil est faux, corrige…
a) Faux. Tous les mélanges d'apparence homogène ne sont pas des solutions. b) Vrai. c) Faux. Dans une solution, plus la concentration est élevée, plus la proportion occupée par le…
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which of these is an example of a physical change? mixing oil and vineg…
C. ALL of these
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which of these is an example of a chemical change? all of these a piece…
A. All of these
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which of these is an example of a chemical change? all of these burning…
A. All of these
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which of these is an example of a chemical change? sugar dissolving in …
C. Rocket fuel burning
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what is the meaning of \stress\? stress is a common condition that affe…
C. When the body is under stress, chemicals in the body react to help us alleviate, control, and eliminate the many symptoms that are associated with the condition.
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which of these is an example of a physical change? all of these mixing …
A. All of these
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question 16 of 25 which scenario is an example of the transfer of therm…
B. A microwave oven causes water molecules in a cup to vibrate faster
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when you observe a chemical property, the substance... remains the same…
C. changes to a new substance
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mass and volume depend on the amount of matter present. this means that…
B. extensive properties
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which of these liquids would have the highest viscosity? rubbing alcoho…
D. Honey
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which is an example of a chemical property? density reactivity with wat…
B. Reactivity with water
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question 14 of 25 which option is an example of chemical energy being t…
B. A battery powering a flashlight
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unruly elements mg - 24 zn - 65 cd - 112 al - 27 p - 31 in - 115 si - 2…
- Where is he from? Russia - What university did he attend? Saint - Petersburg University - In the mid 1800s, there were deep discussions in chemistry about what? Atomic weight - …
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to rent a certain meeting room, a college charges a reservation fee of …
$t<4$
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hear the loud alarum bells, brazen bells! what a tale of terror, now, t…
aaabb
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6. draw and label the water molecule below with: a. element symbol (h o…
For question 6: - The drawing has an oxygen atom in the center labeled "O" and two hydrogen atoms labeled "H" attached to it. - Charged regions: Hydrogen atoms are labeled $\delta…
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6. draw and label the water molecule below with: a. element symbol (h o…
6. a. Draw a water molecule with an 'O' in the center and two 'H's bonded to it. b. Mark the oxygen region with a '-' and each hydrogen region with a '+'. c. Water is a polar mole…
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what is the shape or geometry of ph₃? 1. trigonal planar 2. bent 3. tri…
3. trigonal pyramidal
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use vsepr theory to predict the molecular geometry of the molecule albr…
1. trigonal - planar
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write the electron - dot notation for the element p. 1. . p • 2. : p : …
1. $.\ddot{P}.$
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use vsepr theory to predict the molecular geometry of the molecule cbr₄…
3. tetrahedral
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which of the following has a polar covalent bond? 1. n₂ 2. o₂ 3. kcl 4.…
4. CO
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for each row in the table below, decide whether the pair of elements wi…
| element #1 | element #2 | compound formed? | chemical formula | | --- | --- | --- | --- | | oxygen | strontium | ionic | $SrO$ | | sodium | bromine | ionic | $NaBr$ | | xenon | …
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my heart, i cannot still it, nest that had song - birds in it; and when…
The word "heart" is a stressed syllable in each poem and part of a key image related to the theme.
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measurements show that unknown compound x has the following composition…
$N_2O_5$
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study the following sketch of a molecular orbital (mo) in a homonuclear…
| Property | Answer | |--|--| | Symbol for this MO | $\sigma_{2p}^*$ | | Bonding or antibonding | antibonding | | Energy compared to 2p orbital of separate atom | higher |
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the table below lists information about some diatomic molecules or mole…
| molecule | stable? | diamagnetic or paramagnetic? | bond order | | ---- | ---- | ---- | ---- | | $N_2$ | yes | diamagnetic | 3 | | $Li_2$ | yes | diamagnetic | 1 | | $He_2$ | no…
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complete the table below. some binary molecular compounds name chemical…
| name | chemical formula | |--|--| | dinitrogen monoxide | $N_2O$ | | dinitrogen tetroxide | $N_2O_4$ | | nitrogen dioxide | $NO_2$ | | nitrogen monoxide | $NO$ |
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fill in the name and empirical formula of each ionic compound that coul…
| cation | anion | empirical formula | name of compound | | ---- | ---- | ---- | ---- | | $Cs^+$ | $F^-$ | $CsF$ | cesium fluoride | | $Cs^+$ | $Cl^-$ | $CsCl$ | cesium chloride |…
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decide whether these proposed lewis structures are reasonable. proposed…
1. No, it has the wrong number of valence electrons. The correct number is: 8 2. Yes. 3. No, it has the wrong number of valence electrons. The correct number is: 10
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statement,democritus,dalton all matter is made of tiny pieces. matter i…
| Statement | Democritus | Dalton | |--|--|--| | All matter is made of tiny pieces. | Yes | Yes | | Matter is made of empty space through which atoms move. | Yes | No | | Atoms ca…
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how is energy associated with food stored? a. potential energy in chemi…
A. potential energy in chemical form
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a sea of mobile electrons is characteristic of which bond? 1. metallic …
1. metallic
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polyethylene is a flexible substance that is used in some plastic bags.…
C. It is soft and flexible because it is made of strands of carbon and hydrogen arranged for strength but that bend and slide past each other easily.
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regular chemistry name: savannah jackson date: 10/10 class: 4th unit 2 …
| Metal or Transition Metal | Nonmetal or Polyatomic ion | Formula | Compound Name | |---|---|---|---| | Sodium | Chloride | $NaCl$ | Sodium Chloride | | Calcium | Chloride | $CaC…
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regular chemistry name: savannah jackson date: 10/10 class: 4th unit 2 …
| Metal or Transition Metal | Nonmetal or Polyatomic Ion | Formula | Compound Name | | ---- | ---- | ---- | ---- | | 1. Sodium | Chloride | $NaCl$ | Sodium chloride | | 2. Calcium…
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the word hence... refers to a type of poultry raised by robert frost. r…
D. means as a consequence or in the future.
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ws 2: ionic bonding with transition metals and polyatomic ions make sur…
| Metal or Transition Metal | Nonmetal or Polyatomic ion | Formula | Compound Name | |---|---|---|---| | Sodium | Chloride | $NaCl$ | Sodium chloride | | Calcium | Chloride | $CaC…
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why were the pythagorean theorem and the fibonacci sequence mentioned i…
D. They help you better understand how geometric shapes are used in art.
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why were the pythagorean theorem and the fibonacci sequence mentioned i…
They help you better understand how geometric shapes are used in art.
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what does the \ mean when figuring out lewis dots for covalent compound…
N = how many more valence electrons are needed
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when figuring out lewis dots for covalent compounds what does \a\ mean?…
A = the total available valence electrons of all the atoms
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in a(an) polar bond, one atom pulls on the shared electrons more than t…
True
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what is the name of this element? 80 hg 200.59 iron mercury hydrogen ha…
Mercury
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which of the following is the correct lewis dot structure for the molec…
B. :F - F: with three lone - pairs on each F atom
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name 1. copper (ii) sulfide 2. copper (i) oxide 3. chromium (iii) sulfi…
| Name | Transition Metal Charge | Formula | |---|---|---| | 1. Copper (II) Sulfide | +2 | $CuS$ | | 2. Copper (I) Oxide | +1 | $Cu_2O$ | | 3. Chromium (III) Sulfide | +3 | $Cr_2S…
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name: | name | transition metal charge | formula | | ---- | ---- | ----…
| Name | Transition Metal Charge | Formula | |--|--|--| | 1. Copper (II) Sulfide | +2 | $CuS$ | | 2. Copper (I) Oxide | +1 | $Cu_{2}O$ | | 3. Chromium (III) Sulfide | +3 | $Cr_{2}…
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chemical energy is a form of ____ energy. entropic motion potential hea…
First question: C. potential Second question: E. cellular respiration
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which of the following compounds has an ionic bond? 1. so3 2. hcl 3. na…
3. NaCl
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which of these is exhibiting kinetic energy? a space station orbiting e…
Part A: a space station orbiting Earth Part B: energy cannot be created or destroyed but can be converted from one form to another
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use vsepr theory to predict the molecular geometry of the molecule hi. …
3. linear
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16. mlib 76 1048 10 pts possible which substance has nonpolar covalent …
4. $O_2$
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unit test: the structure of matter read each question. circle the lette…
A. Gas particles are spaced far apart and move around freely.
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q2: what volume, in ml, of 4.0 h₂so₄ is diluted to make 250.0 ml of a 0…
$9.375\ mL$
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regular chemistry name: name redacted date: 10/9 class: 5g ws: ionic bo…
# Explanation: ## Step1: Recall ion charges Sodium ($Na^+$) has a +1 charge, chromate ($CrO_4^{2 -}$) has a - 2 charge. Using the criss - cross method, the formula is $Na_2CrO_4$.…
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what is the shape of asf₃? 1. trigonal pyramidal 2. t - shaped 3. tetra…
1. trigonal pyramidal
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write the electron - dot notation for the element cl. 1. none of these …
5. :$\ddot{\text{Cl}}$:
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which of the following compounds have a covalent bond? 1. kcl 2. rbcl 3…
4. HCl
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two chemicals react in an endothermic reaction. what can be known about…
Heat is absorbed because the old substance needs more energy to break its bonds.
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what is the correct lewis formula for oxygen (o₂)? 1. \\tmplnine 2. \\t…
Without the actual options' content, it's not possible to provide the correct option. Please provide the content of \tmplone - \tmplnine for a proper answer.
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what must occur in order for a chemical reaction to be specifically cla…
Energy is absorbed in the form of heat.
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for a science project, janet performs four experiments that are suppose…
Experiment 1
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when liquid silver nitrate and liquid sodium chloride are combined, sol…
B. silver chloride