化学
化学反应、化学计量、分子结构与元素性质。
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1) what is the honc 1234 rule? (5pts)(put answer here.)2) explain why o…
1) The HONC 1234 rule is a bonding guideline for common organic elements: Hydrogen (H) forms 1 covalent bond, Oxygen (O) forms 2 covalent bonds, Nitrogen (N) forms 3 covalent bond…
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lets write an elegy!!!! an elegy poem is a tribute to someone who has p…
**Elegy for Grandma Elara** The porch swing still sways where you used to sit, (A) Your teacup’s faint ring on the oak still stays, (B) I trace the faint cracks where your fingers…
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stoichiometry & limiting reproblem5. $2\\ hi + ca(oh)_2 \ ightarrow cal…
2.16 grams
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4. $4fe + 3o_2 \ ightarrow 2fe_2o_3$ if 4.7 grams of $fe_2o_3$ (molar m…
Approximately 3.3 grams (or 3.28 grams) of Fe were reacted.
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18. valence electrons are found in the nucleus. true / false 19. the ma…
18. False 19. True 20. False
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elaborate on the reason why heating water up will increase the rate of …
D. The average kinetic energy of the molecules that make up the solution also increases with increasing temperature. This increase in kinetic energy allows the solvent molecules t…
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when a mixture is stirred a the rate of dissolving stops. b the rate of…
B. the rate of dissolving will increase.
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1. a solution is a mixture. the part of the solution in the greater amo…
1. B. solvent 2. A. stir the sugar in the tea 3. A. contact between the solvent and solute
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2. 17.80 grams of naoh is mixed with 15.40 grams of $h_3po_4$$3naoh_{(a…
2a. $\approx 24.3$ grams of $\text{Na}_3\text{PO}_4$ can be formed 2b. The limiting reactant is $\text{NaOH}$ 3a. $\approx 192$ grams of disulfur dichloride is produced 3b. The li…
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4. $\boldsymbol{6 na_{(s)} + fe_{2}o_{3 (s)} ightarrow 3 na_{2}o_{(s)} …
4. a. $\text{Fe}_2\text{O}_3$ b. $\text{Na}$ 5. a. $71.6\ \text{grams}$ Limiting reactant: $\text{AgNO}_3$ Excess reactant: $\text{KBr}$
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4. record the different types of evidence that indicate a chemical chan…
1. Color change (e.g., rust forming on iron, a blue solution turning clear) 2. Formation of a precipitate (a solid forming from mixing two liquids) 3. Gas production (bubbles, fiz…
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what is most closely the meaning of maneuvers in the passage below (par…
A. schemes
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10. a compound is discovered that is 64.9% carbon, 13.5% hydrogen, and …
Empirical formula: $\text{C}_4\text{H}_{10}\text{O}$ Molecular formula: $\text{C}_4\text{H}_{10}\text{O}$
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if the empirical formula is ch and the molar mass is 78 g/mol, what is …
$\text{C}_6\text{H}_6$
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practice: determining formulas part 1: determine the empirical formula,…
1. Empirical formula for magnesium-bromine compound: $\text{MgBr}_2$ 2. Empirical formula for carbon-hydrogen compound: $\text{CH}_4$
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11/02/26 q6) write short note on chemical bonding q16) give the types o…
1. **Q6**: Chemical bonding is the attractive force that holds atoms, ions, or molecules together to form stable chemical compounds, driven by interactions between valence electro…
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1. in any solution, the part in the greatest quantity or volume is call…
1. B. solvent 2. A. liquid-solid 3. gas-gas
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chapter review (continued)directions: find the mistakes in the statemen…
11. A burning candle is undergoing a chemical change. 12. Removing salt from water by heating the water until it vaporizes and leaves the salt behind is called evaporation. 13. An…
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reviewpart a. vocabulary reviewdirections: use the clues below to compl…
### Completed Crossword Answers: Across: 1. PHYSICAL 3. COMPOUND 4. HETEROGENEOUS 6. SUSPENSION 7. COLLOID 9. MIXTURE 10. SOLUTION Down: 2. HOMOGENEOUS 5. ELEMENT 8. TYNDALL 9. MA…
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lines 21-24 a. write: how is this stanza similar to stanza 1 (lines 1-4…
1. Rhyme scheme labeling (lines 21-43): Lines 21-24: A, B, A, B Lines 25-28: C, C, D, D Lines 29-32: E, F, E, F Lines 33-34: G, G Lines 35-38: H, I, H, I Lines 39-43: J, K, L, L, …
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directions: below are two sets of words. complete the second set by cho…
1. ice 2. solubility 3. condensation 4. flammable 5. air 6. iron 7. burning logs 8. wire 9. A physical change only changes a substance's physical form (no new substance is formed)…
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is a. $8g$ b. $4g$ c. $g$ d. $16g$ 10. an aeroplane gets its upward lif…
10. b. Bernoulli's principle 11. c. Kinetic energy is maximum, potential energy is minimum 12. a. $\lambda/4$ 13. a. Both A and R are true and R is the correct explanation of A. 1…
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order these compounds based on the strength of the dipole-dipole forces…
D. $\text{HCl} > \text{HBr} > \text{HI}$
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identify the correct dipole for the c$-$br bond in the lewis structure …
II. $\ce{H - \underset{\underset{H}{|}}{C} - H}$ with arrow pointing from C to Br (positive end on C, arrowhead on Br)
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which has the correct name-formula combination? answer: a chlorine pent…
C. carbon tetraiodide - $\text{CI}_4$
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what is the last portion of the electron configuration for gallium, ga?…
4p¹
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what is the noble gas electron configuration for polonium? xe 6s² 5d¹⁰ …
[Xe] 6s² 4f¹⁴ 5d¹⁰ 6p⁴
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which is the correct electron configuration for the element phosphorus?…
1s² 2s² 2p⁶ 3s² 3p³
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what element does this orbital diagram represent? na ar ne k
Na
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what element does this electron configuration represent? $kr 5s^2 4d^{1…
I. Iodine (I)
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name: daniela torres count how many atoms for each compound or molecule…
1. $\text{NaHCO}_3$: 1 Na, 1 H, 1 C, 3 O 2. $\text{Mg(OH)}_2$: 1 Mg, 2 O, 2 H 3. $2\text{H}_2\text{SO}_4$: 4 H, 2 S, 8 O 4. $\text{C}_2\text{H}_4\text{O}_2$: 2 C, 4 H, 2 O 5. $3\t…
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count how many atoms for each compound or molecule $ce{nahco_{3}}$ $na=…
1. $\text{NaHCO}_3$: 6 total atoms (1 Na, 1 H, 1 C, 3 O) 2. $\text{Mg(OH)}_2$: 5 total atoms (1 Mg, 2 O, 2 H) 3. $2\text{H}_2\text{SO}_4$: 14 total atoms (4 H, 2 S, 8 O)
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physical science eams counting atoms count how many atoms for each comp…
- $\text{NaHCO}_3$: 6 total atoms (Na=1, H=1, C=1, O=3) - $\text{C}_2\text{H}_4\text{O}_2$: 8 total atoms (C=2, H=4, O=2) - $\text{Mg(OH)}_2$: 5 total atoms (Mg=1, O=2, H=2) - $3\…
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eams counting atoms date name count how many atoms for each compound or…
1. For $\boldsymbol{\text{NaHCO}_3}$: - Sodium ($\text{Na}$): 1 atom - Hydrogen ($\text{H}$): 1 atom - Carbon ($\text{C}$): 1 atom - Oxygen ($\text{O}$): 3 atoms - Total atoms: 6 …
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physical science eams counting atoms date name count how many atoms for…
1. For $\text{NaHCO}_3$: 6 total atoms (1 Na, 1 H, 1 C, 3 O) 2. For $\text{C}_2\text{H}_4\text{O}_2$: 8 total atoms (2 C, 4 H, 2 O) ### Molecule Drawing Notes: - $\text{NaHCO}_3$ …
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ms-ess2-1 develop a model to describe the cycling of earths materials a…
6. C. It is not a mineral because it doesn't have a crystal structure. 7. C. pressure
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9. use the following chemical equation to solve the 3 step problem and …
Balanced equation: $3\text{Mg} + \text{N}_2 ightarrow \text{Mg}_3\text{N}_2$ a. $\approx 35\ \text{g}$ (rounded to 2 significant figures) b. Completed table: | Moles Mg | Moles N₂…
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7. complete the table using the following reaction. balance the equatio…
(Problem 7 Table): | Moles Fe | Moles O₂ | Moles Fe₂O₃ | Excess Fe | Excess O₂ | Limiting Reactant | |----------|----------|-------------|-----------|-----------|-----------------…
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a solid oxide of lead, $\text{pbo}_2(s)$, reacts with $\text{h}_2\text{…
C. The Pb in $\text{PbO}_2$ is reduced.
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photoelectron spectrum identify the element in this pes graph. calcium …
Calcium
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6. what is the maximum amount (in grams) of nacl that can be produced f…
Balanced reaction: $\boldsymbol{2Na + Cl_2 ightarrow 2NaCl}$ a. Moles of Na: $\boldsymbol{\approx 1.96\ \text{mol}}$ b. Moles of NaCl from Na: $\boldsymbol{\approx 1.96\ \text{mol…
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5. how many grams of carbon dioxide should be produced if 25.0 g of oct…
Theoretical yield of $\ce{CO2}$: $31.4\ \text{g}$ Percent yield: $93.9\%$ Percent error: $6.11\%$
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molarity mastery 2020.pdf making solutions..... 6. using the steps belo…
1. (For Question 6) a. Fill flask with half the needed volume of water. b. Add calculated mass of salt to water, stir to dissolve. c. Fill flask to the marked volume line. 2. (For…
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what is the chemical that refluxes into the esophagus, causing the burn…
Hydrochloric acid (HCl)
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molarity masterydiagramming the concept...1. use this diagram 2 m deter…
1. $\boldsymbol{0.5\ \text{M}}$ 2. Evaporate solvent to reduce the solution's volume to half of its original volume, or add an equal number of moles of calcium chloride to the ori…
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write the formula for these ionic compounds: iron (ii) chloride calcium…
1. Iron (II) Chloride: $\text{FeCl}_2$ 2. Calcium Oxide: $\text{CaO}$ 3. Sodium Sulfide: $\text{Na}_2\text{S}$ 4. Aluminum Nitride: $\text{AlN}$ 5. Magnesium Oxide: $\text{MgO}$ 6…
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16. what is the formula for iron (iii) bromide?febrfebr₂febr₃fe₃br17. w…
16. $\text{FeBr}_3$ 17. $\text{CaS}$ 18. $\text{PCl}_3$ 19. $\text{C}_2\text{F}_6$ 20. Nitrate 21. Magnesium nitride 22. Barium chloride 23. Dinitrogen pentoxide 24. Sulfur trioxi…
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7. what is the charge of a potassium ion? a) +1 b) -1 c) -2 d) +2 8. wh…
7. a) +1 8. c) -2 9. b) zero 10. 3+ is the charge 11. have 8 valence electrons 12. SO₂ 13. CaCl₂ 14. Ar 15. (OH)⁻
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unit 3 practice test/study guide 1. what type of solid can conduct elec…
1. Ionic compound 2. Metal 3. Ionic compound 4. Electrons are transferred between metals and nonmetals. 5. Atoms share electrons 6. two or more metals
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question 25 of 36 the boiling point of an aqueous solution is 102.01 °c…
$-7.30^\circ\text{C}$
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question 24 of 36 > imagine two solutions with the same concentration a…
$m = 0.420$ m $T_b = 78.9$ °C
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at -13.0 °c, a common temperature for household freezers, what is the m…
3090 g (rounded to 3 significant figures)
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question 22 of 36 a solution is made by dissolving 0.735 mol of nonelec…
$T_f = 1.1^\circ\text{C}$ $T_b = 82.3^\circ\text{C}$
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which of the following phase changes is the largest decrease in entropy…
1. deposition 2. melting
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which of the following phase changes is the largest increase in entropy…
1. sublimation 2. condensation
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question 21 of 36 calculate the freezing point of a 12.25$m$ aqueous so…
$-22.79^\circ\text{C}$ (rounded to two decimal places, or $-22.8^\circ\text{C}$ for reasonable precision)
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a solution is made by mixing 38.0 ml of ethanol, $ce{c_{2}h_{6}o}$, and…
21.7 Torr
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biphenyl, $\text{c}_{12}\text{h}_{10}$, is a nonvolatile, nonionizing s…
$81.9\ \text{Torr}$
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a chemist combined chloroform (chcl₃) and acetone (c₃h₆o) to create a s…
2.71 M
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who is the limiting reactant? ______ who is the excess reactant? ______…
1. Ecuación química balanceada: $\boldsymbol{\text{SiO}_2 + 3\text{C} ightarrow \text{SiC} + 2\text{CO}}$ 2. Reactivo limitante: $\boldsymbol{\text{SiO}_2}$ (el carbono está en ex…
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when 4.74 g of a nonelectrolyte solute is dissolved in water to make 15…
concentration: $0.0520$ M moles of solute: $0.00806$ mol molar mass: $588$ g/mol
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two beakers each contain 200 ml of water. into one beaker, a student ad…
The NaCl solution will have a higher boiling point than the KCl solution.
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if a 0.510 $m$ aqueous solution freezes at $-2.90\\ ^\\circ\\text{c}$, …
$3.06$
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question 34 of 36 assuming 100% dissociation, calculate the freezing po…
$T_f = -14.4^\circ\text{C}$ $T_b = 103.9^\circ\text{C}$
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when 12.3 g of an organic compound known to be 62.04% c, 10.4% h, and 2…
$\text{C}_6\text{H}_{12}\text{O}_2$
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a metal, m, of atomic mass 56 amu reacts with chlorine to form a salt t…
$\text{MCl}_2$ (or specifically, $\text{FeCl}_2$, since M has atomic mass 56 amu, iron)
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read the lines from \the tide rises, the tide falls.\along the sea-sand…
It strengthens the connection between the two lines.
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average chemical composition— set 1 —— set 2 —1. earths hydrosphere is …
1. (2) liquid water layer of Earth 2. (4) oxygen and silicon 3. (2) oxygen 4. (4) 5. (2) hydrogen 6. (1) iron 7. (1) the crust 8. (1) O and Si 9. (3) iron
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4. based on the following balanced equation, $2\\text{fe}(s) + 3\\text{…
a. +3 (Iron(III) ion, $\text{Fe}^{3+}$) b. $0.01398$ moles
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6) what is the percent yield of $\text{co}_2(g)$ if 46.5 grams of $\tex…
6. $\approx 64.0\%$ 7. $\approx 69.2\%$ 8. $\approx 129\ \text{g}$ (rounded to 3 significant figures) 9. $\approx 142\ \text{g}$ (rounded to 3 significant figures) 10. $\approx 92…
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write the balanced chemical formula for photosynthesis in symbols and w…
## In Symbols: ### Reactants: $6\text{CO}_2 + 6\text{H}_2\text{O}$ (plus light energy, chlorophyll) ### Products: $\text{C}_6\text{H}_{12}\text{O}_6 + 6\text{O}_2$ Balanced equati…
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3. based on the following balanced equation, fe (s) + cuso₄(aq) → feso₄…
a. +2 (or 2+) b. 0.009321 mol
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of 9.0 moles of potassium chlorate (kclo₃)? 4. ____ c₆h₆o + ____ o₂ → _…
0.8 moles of $\ce{O2}$ reacted.
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4. $\boldsymbol{2 c_6h_6o + 11 o_2 ightarrow 12 co + 6 h_2o}$ how many …
1.1 moles
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critical thinking: why is the number of valence outer shell electrons m…
(Visual description of the Bohr model: A central red oxygen nucleus, surrounded by a second electron shell with 8 electrons (4 as unpaired dots, 2 pairs each connected to a hydrog…
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periodic table literacy understanding element tiles before determining …
### Understanding Element Tiles #### Sodium - Atomic Number: $11$ - Symbol: $\text{Na}$ - Atomic Mass: $22.99$ #### Carbon - Atomic Number: $6$ - Symbol: $\text{C}$ - Atomic Mass:…
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read the poem. paul reveres ride by henry wadsworth longfellow (1) list…
It creates an eerie, suspenseful mood.
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name: date: 2/10/26 block: reading: the nature of chemical bondsreading…
| Ionic Bonds | Covalent Bonds | |-------------|----------------| | Forms via electron transfer | Forms via electron sharing | | Occurs between metal + non-metal | Occurs between …
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question① what is the name for the acid with the formula $\text{hno}_2$…
Nitrous acid
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question given the formula for borate as $bo_3^{3-}$, what is the formu…
$\text{H}_3\text{BO}_3$ (the second option)
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question ① what is the formula for chromous acid? answer $ce{h_{2}cr_{2…
$\text{H}_2\text{CrO}_2$
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question what acid is formed from the bromide ion? answer $h_2br$ $hbr$…
B. HBr
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question what is the name for the acid with the formula $h_3po_5$? answ…
Perphosphoric acid
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question ⓘ identify the formula for permanganic acid. answer $h_2mno_4$…
B. $\text{HMnO}_4$
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question ① which pair correctly matches the name for an acid with its f…
A. Sulfuric acid, $\text{H}_2\text{SO}_4$
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question 1 identify the formula for pernitric acid. answer hno hno₃ h₂n…
$\boldsymbol{\text{HClO}_4}$ (Note: correcting a potential typo in the options, as the intended correct formula for perchloric acid is $\text{HClO}_4$; if the last option was mean…
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questionwhat is the name for the acid with the formula hi?answeriodous …
Hydroiodic acid
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since the video is playing in reverse, this represents the solid produc…
The mass of $\text{NaHCO}_3$ required is approximately $\boldsymbol{3.57\ \text{g}}$, with the dimensional analysis filled as: $2.29\ \text{g}\ \text{Na}_2\text{CO}_3 \times \frac…
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question identify the formula for chromic acid. answer $hcro_4$ $h_2cro…
$\boldsymbol{\text{H}_2\text{CrO}_4}$ (the second option)
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show the dimensional analysis set-up needed to calculate the mass of na…
The complete dimensional analysis setup is: $2.29\ \text{g}\ \text{Na}_2\text{CO}_3 \times \frac{1\ \text{mol}\ \text{Na}_2\text{CO}_3}{105.99\ \text{g}\ \text{Na}_2\text{CO}_3} \…
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2. you used stoichiometry to predict how many grams of solid product wo…
Reaction 4 (the decomposition of $\text{NaHCO}_3$ to $\text{Na}_2\text{CO}_3$, $\text{CO}_2$, and $\text{H}_2\text{O}$) occurred, as its predicted solid product mass (4.1181 g) is…
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the diagram below is a model of two solutions. each yellow ball represe…
Solution B
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the diagram below is a model of two solutions. each purple ball represe…
Solution B
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20. if reaction #4 occurs, you calculated that 0.03885 moles $ce{na_{2}…
$4.1181$ g
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19. use the equation you built in the previous problem. calculate how m…
0.03885 mol
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18. construct the mole ratio needed to calculate how many moles of $ce{…
Filled equation: $0.0777\ \text{mole NaHCO}_3 \times \frac{1\ \text{mole Na}_2\text{CO}_3}{2\ \text{mole NaHCO}_3} = 0.03885\ \text{mol Na}_2\text{CO}_3$ Final moles of $\text{Na}…
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17. last one! predict the mass of the solid that remains if reaction #4…
The balanced coefficients (in order) are 2, 1, 1, 1. The coefficient for $\text{NaHCO}_3$ is $\boldsymbol{2}$.
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the diagram below is a model of two solutions. each pink ball represent…
Solution B
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16. if reaction #3 occurs, you calculated 0.03885 moles $ce{na_{2}o}$ w…
$2.408\ \text{g}\ \text{Na}_2\text{O}$
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the diagram below is a model of two solutions. each blue ball represent…
Solution A