化学
化学反応、化学量論、分子構造、元素の性質。
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4. true or false: in order for katie to hear paul, air molecules must *…
False
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how to calculate molar mass (molecul... molar mass in 3 easy steps watc…
- \( \ce{MgCl2} \) matches \( 95.205 \, \text{g/mol} \) - \( \ce{(NH4)2CO3} \) matches \( 96.086 \, \text{g/mol} \) - \( \ce{C9H9O4} \) matches \( 181.050 \, \text{g/mol} \)
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individual elements. it is linked here -> periodic table. *** remember …
The total mass of the compound is $310.178$ g/mol. For each element: - Ca: $3\times40.078 = 120.238$ g/mol - P: $2\times30.974 = 61.948$ g/mol - O: $8\times15.999 = 127.992$ g/mol
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using the symbols in the parenthesis and the number of each color from …
B. \( \text{GO}_4\text{PY}_2\text{Pu}_6\text{Wh} \) (assuming the second option is labeled B, as per the options given with O having subscript 4, Y subscript 2, Pu subscript 6 and…
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match the package to the number. mole reem of paper dozen pair 12 500 2…
- Mole: \(6.02\times10^{23}\) - Reem of paper: 500 - Dozen: 12 - Pair: 2
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a) a strong base b) a weak acid c) a strong acid d) a weak base →9. a s…
9. b) a base 10. c) remains red
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b) concentrate strong acid c) dilute weak acid d) concentrate weak acid…
7. a) dilute strong base 8. d) a weak base
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1. a solution has a ph of 4. the solution is (acidic)/ basic. 2. a solu…
1. acidic 2. basic 3. neutral 4. dilute 5. concentrate 6. b) concentrate strong acid 7. dilute strong base
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covalent compound naming first, identify whether these compounds are io…
| # | Chemical Formula | Type of Compound: Ionic or Covalent | Compound Name | |----|----|----|----| |21)|$\text{CdBr}_2$|Ionic|Cadmium Bromide| |22)|$\text{Cr(Cr}_2\text{O}_7\tex…
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all chemicals in the lab should be considered dangerous true false pipe…
1. True 2. False 3. False 4. False
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if an acid is splashed on your skin, wash it at once with ○ soap ○ oil …
1. plenty of water 2. wash your hands thoroughly with soap and water 3. True
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personal eyeglasses provide as much protection as a face shield safety …
1. none of the above 2. tied back and kept away with hairband, pins, etc. 3. all of the above
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if you wear contact lenses in the school laboratory 1 point ○ take them…
1. take them out before starting the lab 2. ask the instructor before proceeding 3. disposed of according to your instructor's directions
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if a laboratory fire erupts, immediately: - notify your instructor - ru…
1. notify your instructor 2. anytime chemicals, heat or glassware are used
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what might cause chemical weathering volcanic eruptions growing plants …
C. Acid Rain
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why does ice float? as water freezes, air becomes trapped between the h…
B. As water freezes, it expands and its density decreases.
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montgomery county public schools draft 2018 hs ngss chemistry naming bi…
1. $\text{N}_2\text{O}_3$: dinitrogen trioxide 2. $\text{SCl}_2$: sulfur dichloride 3. $\text{IF}_5$: iodine pentafluoride 4. $\text{SiCl}_4$: silicon tetrachloride 5. $\text{BCl}…
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refer to paragraphs 4 and 5. the author says that president roosevelt a…
1. Roosevelt’s crafty plan failed, but the Supreme Court did keep social security and several other New Deal programs in place. 2. In time, some of the older justices retired or d…
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question 8 (1 point) what is the molar mass of potassium chloride, kcl …
74.55 g/mol ### Question 9:
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question 7 (1 point) what is the molar mass of magnesium metal, mg from…
The molar mass of Magnesium (Mg) is approximately 24.305 g/mol.
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what is the molar mass of the element a 1.008 b 15 c 1 d 30.974
a. 1.008
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question 5 (1 point) which of the following would have the highest amou…
d. 10.0 mole of Magnesium, Mg ### Question 6 (Avogadro's Number)
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what is the molar mass of the compound, potassium chloride, kcl? k = 39…
b. 74.548 ### Second Question (Molar Mass of CaS)
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what is the molar mass of the element hydrogen - h? a 1 b 15 c 30.974 d…
d. 1.008
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question 1 (1 point) what is the molar mass of the element tellurium - …
d. 127.60
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one of the best ways to succeed in college is by devising and adhering …
C. "downtime"
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elo week 1 explain how figurative lan... one of the best ways to succee…
C. by suggesting that students need to take time to consider their priorities
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one of the best ways to succeed in college is by devising and adhering …
B. It contributes to the informality.
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one of the best ways to succeed in college is by devising and adhering …
A. by suggesting that the specificity of the schedule is important
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a science lab team was questioning how best to describe sound energy. t…
Dixie
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name: teacher: date: q2 chemistry: unit 4 exam review use the following…
Diagram B ### Question 6
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name: q2 chemistry: unit 4 exam review date: prepwork part 1: mixed pra…
E. 5 ### Question 4
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what is the mass of ice in grams of a 0.485 cm³ sample if its density i…
1. $0.445\ \text{g}$ 2. $0.0304\ \text{cm}^3$ 3. $3.02\ \text{g}$ 4. $2.94\ \text{mL}$ 5. $6.96\ \text{g/cm}^3$
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review for midterm, ws#6 bonding 1. fill in the best answer for each of…
1. a) valence b) 2 c) +1 d) 4 e) 8 f) gaining; losing g) share h) lose i) Valence Shell Electron Pair Repulsion j) Argon (Ar) k) Helium (He) l) crystal lattices m) negative (-) n)…
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how many atoms of p are present in a sample of p₂o₅ that contains 5.2 ×…
2.1 x 10²³ atoms of P
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there are $1.2 \\times 10^{24}$ atoms of carbon in a sample of aluminum…
3.0 moles H (Option: 3.0 moles H)
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calculate the mass in grams of 64.0 ml of chloroform, an anesthetic tha…
$95.3\space g$
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there are 2.5 moles of hydrogen in a sample of aluminum acetate, al(c₂h…
0.28 moles $Al(C_2H_3O_2)_3$
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if a blood sample has a mass of 231. g and a volume of 232. ml, what is…
$0.996$
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there are $1.5 \\times 10^{24}$ atoms of carbon in a sample of aluminum…
0.42 moles Al
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how many molecules of vitamin a, c₂₀h₃₀o, are in a sample that contains…
B. \( 2.0 \times 10^{21} \) molecules of \( \text{C}_{20}\text{H}_{30}\text{O} \)
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convert this temperature to °c. be sure your answer has the correct num…
477 K (or 477.15 K, but considering significant figures from 204, 477 K is suitable)
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how many atoms of p are present when a p₂o₅ sample contains 5.2 × 10²³ …
\( 2.08 \times 10^{23} \) atoms P (So the green box is 2.08 and the yellow box is 23)
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how many moles of s are present in 3.6 × 10²⁴ formula units of al₂s₃? p…
Approximately \( \boldsymbol{18} \) moles (or more precisely \( \approx 17.9 \) moles) of \( \text{S} \) are present. (Note: If we use \( 6.02 \times 10^{23} \) for Avogadro's num…
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a cake is baked at 400. °f. part: 0/2 part 1 of 2 convert this temperat…
$\approx 204^\circ\text{C}$ (or $200^\circ\text{C}$ depending on significant figures; but more accurately, approximately 204 $^\circ\text{C}$)
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we want to determine how many molecules of c₁₂h₂₂o₁₁ are present when a…
B. \( \frac{1\text{ mlc }C_{12}H_{22}O_{11}}{12\text{ atom }C} \)
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which of these is not a correct internal conversion for c₁₂h₂₂o₁₁? note…
B. \( \frac{1\ \text{mlc}\ \text{C}_{12}\text{H}_{22}\text{O}_{11}}{12\ \text{mole}\ \text{C}} \)
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yana uses 16.4 liters of helium to blow up a balloon for a party. if th…
\( 0.732 \) (or if we consider that maybe the molar volume is taken as 22.4 L/mol exactly, then the calculation is as above. So the number of moles is approximately \( 0.732 \) mo…
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gingerol, c₁₇h₂₆o₄, is a compound similar to capsaicin that is being st…
0.510 (or 0.5096, depending on significant figures; 150.0 has 4 sig figs, molar mass calculation gives ~294.38, so result should have 4 sig figs? Wait, 150.0 is 4, 294.378 is ~6, …
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a gas water heater generates co₂ and co gas as byproducts of combustion…
314
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what is the volume of 8.25 moles he at stp?? l heremember, 1 mole = 22.…
185 L (Wait, no, wait, 8.25 *22.4 = 184.8. If we consider significant figures, 8.25 has three, 22.4 has three, so the result should have three. 184.8 rounded to three significant …
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which conversion factor allows us to move between moles and gas volume …
1 mole = 22.4 L
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what is the mass of 4.0 moles of sodium, na? ? g na remember, 1 mole = …
92 (or 91.96 depending on precision, but with significant figures from 4.0, 92 g)
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which conversion factor allows us to move between moles and mass? 1 mol…
B. 1 mole = molar mass (assuming the options are labeled A, B, C with the second option as B; if the original options have different labels, adjust accordingly based on the second…
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carry out each calculation and give the answer using the proper number …
\(197.1\space mL\) ### Part 2:
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how many atoms are in 4.0 moles of sodium, na? ? × 10^? atoms na rememb…
The coefficient (green box) is \(2.4\) and the exponent (yellow box) is \(24\), so the number of atoms is \(\boldsymbol{2.4\times 10^{24}}\) atoms Na.
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which conversion factor allows us to move between moles and atoms? 1 mo…
1 mole = \(6.02 \times 10^{23}\) particles
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carry out each calculation and give the answer using the proper number …
\( 197 \) (or \( 197.1 \) depending on interpretation, but likely \( 197 \) as three significant figures) ### Part 2 of 2
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ethanol is the common name for a compound used as an antiseptic and a d…
\(46.07\) (or \(46.068\))
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acetylsalicylic acid is a pain reliever, fever reducer, and anti - coag…
\(180.15\) (or \(180.154\)) g/mol
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a single atom of sodium has a mass of 22.99 amu. what is the mass, in g…
22.99
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a single atom of calcium, ca, has a mass of 40.08 amu. what is the mass…
40.08
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consider the true analogy showing the relationship between amu and gram…
3. (Ni) 59 amu : atom :: 58.69 g : mole
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carry out each calculation and give the answers using the proper number…
\(20.0\)
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puzzlemaker is a puzzle generation tool for teachers, students and pare…
### Across: 3. METALLIC 7. COVALENT 8. BONDING 9. PROTONS 12. FAMILIES (filled) 13. NITROGEN 14. ATOMIC RADIUS 16. [Teacher's Name, e.g., SMITH] 17. MERCURY ### Down: 1. OXYGEN 2.…
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consider the isotope notation shown. $\\ce{^{45}_{21}sc}$ how many neut…
24 (corresponding to the option with 24, e.g., if the option is labeled as B. 24, then B. 24)
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consider the isotope notation shown. \\(\\ce{^{45}_{21}sc}\\) how many …
21 (corresponding to the option with 21, e.g., if the option is labeled as, say, C. 21, then C. 21)
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consider the isotope notation shown. \\(\\ce{^{45}_{21}sc}\\) how many …
21 (corresponding to the option "21")
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consider the isotope notation shown. $\\ce{^{13}_{6}c}$ how many neutro…
7 (corresponding to the option with 7)
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consider the isotope notation shown. \\(\\ce{^{13}_{6}c}\\) how many el…
A. 6
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consider the isotope notation shown. $ce{_{6}^{13}c}$ how many protons …
6
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how many isotopes are represented for the element in this mass spectrum…
Wait, the x - axis is 81, 83, 85, 87, 89. The peaks are at 85, 87, 89. So three peaks. So the number of isotopes is 3? No, wait maybe the first peak (small) at 85, then a peak at …
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the mass spectrum shows the stable isotopes for an element. what elemen…
C. Sr
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what element does this graph most likely represent? unknown element rel…
Titanium
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Question was provided via image upload.
Bromine
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what is the average atomic mass of this element based on the data? isot…
91.32
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how many isotopes are present for this compound? unknown element percen…
B. three isotopes
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calculate the average atomic mass for this element. isotope - mass | pe…
The average atomic mass of the element is approximately $87.71$ (units are atomic mass units, usually).
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read the excerpt from \sonnet 29\ when, in disgrace with fortune and me…
abab
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how is a poems rhyme scheme marked and identified? upper or lowercase l…
A. upper or lowercase letters, such as "ABAB"
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markus is reading a sonnet by william shakespeare. which will best help…
finding a single concept that links the lines together
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read the excerpt from ovids \pyramus and thisbe\. the blood leaped high…
The figurative language describes the violence of the scene.
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question 4 the ______________ states that matter is neither created nor…
1. Question 4: Law of Conservation of Mass 2. Question 5: bubbles, temperature change 3. Question 6: 112
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Question was provided via image upload.
(Question 5): Yes, the masses obey the Law of Conservation of Mass (LCM). The total mass of reactants ($80\ \text{amu}$) equals the total mass of products ($80\ \text{amu}$), so m…
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do the following for questions 2-5: count the atoms of each element and…
2. Balanced equation: $\boldsymbol{2\text{NaCl} ightarrow 2\text{Na}^+ + 2\text{Cl}^-}$ (add 1 more $\text{Na}^+$ particle to the products) 3. The given coefficient 2 for $\text{H…
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question 10 10 pts in part 2 of the lab you practice balancing chemical…
Yes
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question 8 when looking at the chemical reaction below, the 2 in front …
Question 8: There are 2 water molecules Question 9: No
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question 3 10 pts the sodium bicarbonate and acetic acid are examples o…
Question 3: A. Reactants Question 4: B. Law of Conservation of Mass
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question 1 10 pts in the lab, mixing the sodium bicarbonate and acetic …
gas, increases
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what is a structural characteristic of a litany poem? (1 point) the sta…
Many lines or stanzas begin with the same word or phrase.
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57. draw the correct lewis structure, determine shape and polarity of t…
See the detailed breakdown above for Lewis structures, geometries, and polarities of $\ce{OCl2}$, $\ce{SO2}$, $\ce{NH4+}$, $\ce{PCl3}$, $\ce{NO2-}$, and $\ce{CH2Cl2}$.
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question 2 2 pts incineration is a waste management process that can ge…
If inorganic material is incinerated, toxic ash might be produced.
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organic chemistry problem set – unit assignment you may refer to your c…
### 1a) Structural Diagram of Octane # Explanation: ## Step1: Determine Formula Octane is an alkane with 8 carbons, formula $C_8H_{18}$. ## Step2: Draw Carbon Chain Draw a straigh…
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the metal bar shown is an alloy of silver and other metals. 7.5 ounces …
0.675 ounces
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3 who first formulated the law of conservation of matter? a isaac newto…
3. c. Antoine Lavoisier 4. c. Mass remains constant 5. b. The molecules change state but remain present 6. c. It emphasizes the rearrangement of atoms rather than their creation o…
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electron is working on a formula that will turn trash into fuel. he nee…
3 ounces
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element | reactant | product h | 4 | 4 o | 2 | 2 are both sides of the …
1. Yes, both sides of the equation are equal (4 H atoms and 2 O atoms on each side). 2. Yes, this equation follows the law of conservation of matter, as the number of each type of…
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for the following reactions, recall the concepts for balancing equation…
### Part a: | Reactants | | | | Products | | | | |--|--|--|--|--|--|--|--| | $\boldsymbol{6CO_2}$ | C: 6 | O: 12 | $\boldsymbol{6H_2O}$ | H: 12 | O: 6 | | | | $\boldsymbol{C_6H_{1…
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10. for the chemical reactions below, label the reactants and products …
## Part a Missing Mass: $206.8\ \text{g}$ Does this equation follow the Law of Conservation of Matter? Yes ## Part b Missing Mass: $37.1\ \text{g}$ Does this equation follow the L…
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8. what are the potential environmental consequences if construction st…
- Sedimentation in water bodies: Smothers aquatic habitats, reduces water clarity, and harms aquatic life. - Water pollution: Pollutants (chemicals, oil, grease) from construction…