化学
化学反应、化学计量、分子结构与元素性质。
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1 multiple choice 5 points in a lab where students measure the mass of …
Measuring reactants separately and carefully before mixing
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6. terica is dissolving a substance in a solution for a chemistry exper…
$-\frac{20}{3}$ grams per second
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did you build a biogeochemical cycle? match biogeochemical cycle charac…
1. An element flows through a system - Nitrogen flows through the marine system 2. An element is in organisms and abiotic substances - Nitrogen is in the atmosphere, water environ…
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why should you never eat or drink in the science lab? because it’s mess…
Because food and drinks can become contaminated with chemicals
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draw the lewis structure for the clo₃⁻ ion. predict its geometry and de…
The Lewis structure has Cl as the central atom, single - bonded to two O atoms (each with 3 lone - pairs) and double - bonded to one O atom (with 2 lone - pairs) and overall charg…
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complete the sentence with the word that best fits the overall meaning …
prevalent
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directions for each problem: 1) recognize and record individual element…
1) H: 2, O: 1, total atoms: 3 2) Mg: 1, Cl: 2, total atoms: 3 3) Li: 2, S: 1, O: 4, total atoms: 7 4) Na: 1, C: 2, H: 3, O: 2, total atoms: 8 5) N: 1, H: 4, Cl: 1, total atoms: 6 …
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part 2 of 3 select the single best geometry of clo₃⁻ ion. trigonal plan…
Part 2 of 3: D. Trigonal pyramidal Part 3 of 3: $sp^{3}$
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what are the hybrid orbitals of the carbon atoms in the following molec…
$sp^2$, $sp^3$
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consider the molecule tetracyanoethylene: :n≡c :n≡c c=c c≡n: c≡n: part …
Part 1 of 2: 9 Part 2 of 2: 9
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consider the molecular shape of water (h₂o). select the single best ans…
Part 1 of 2: Bent Part 2 of 2: $sp^3$
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in hybridization in incl₄⁻. select the single best answer. ○ sp² ○ sp³ …
$sp^3$
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identify the hybridization of the in atom in both the reactant, incl₃, …
$sp^{2}$
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a student has samples of two pure compounds, xclo₃ and zclo₃, which con…
A. Which has the greater molar mass, X or Z?
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given the following information, what is the expected order of elution …
D. A, B, C
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predict the geometries of the following ion. sif$_{6}^{2 - }$ part 1 of…
Part 1 of 2: Electron Domain Geometry: Octahedral Part 2 of 2: Molecular Geometry: Octahedral
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using the vsepr model, predict the molecular geometry of scl₄. select t…
seesaw
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a student has two samples of nacl, each one from a different source. as…
A. Which sample has the higher purity?
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using the vsepr model, predict the molecular geometry of po₄³⁻. select …
tetrahedral
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two different ionic compounds each contain only copper and chlorine. bo…
B. What is the formula unit of each compound?
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is the molecule polar or nonpolar? select the single best answer. polar…
Nonpolar
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consider the polarity of the following molecules. part 1 of 2 is the mo…
Polar
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which structure has a dipole moment? neither structure has a dipole mom…
The first structure has a dipole moment.
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the c₂h₂cl₂ molecule can exist in either of the following two forms: pa…
Part 1 of 2: $sp^2$ Part 2 of 2: The first (cis - isomer) structure
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given this table of electronegativities: atom electronegativity h 2.2 c…
\(CBr_4<NI_3<H_2O<HF\)
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part 3 of 4 tebr₄ electron domain geometry: select molecular geometry: …
For TeBr₄: Electron Domain Geometry: Trigonal bipyramidal Molecular Geometry: Seesaw For SF₆: Electron Domain Geometry: Octahedral Molecular Geometry: Octahedral
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using the vsepr model, predict the electron domain geometry and the mol…
Part 1 of 4 NBr₃ Electron Domain Geometry: tetrahedral Molecular Geometry: trigonal pyramidal Part 2 of 4 XeO₄ Electron Domain Geometry: tetrahedral Molecular Geometry: tetrahedral
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question 9 1 pts what happened to the color of the drops of the starch …
D. Black to Amber
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question 5 2 pts in the starch - acid hydrolysis experiment: a. which r…
A. IKI B. Benedict's
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directions: 1. label each part of the formula reactant 2. complete the …
| Element | Coefficient | Subscript | Total | | ---- | ---- | ---- | ---- | | $N$ | 2 | 2 | 4 | | $O$ | 1 | 2 | 2 |
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directions: 1. label each part of the formula reactant 2. complete the …
| Element | Coefficient | Subscript | Total | | ---- | ---- | ---- | ---- | | N | 2 | 2 | 4 | | O | 1 | 2 | 2 |
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how many moles of k are in 106.15 grams? drag and drop the information …
$2.71\ mol\ K$
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rubidium (rb) has two naturally occurring isotopes: rb - 85 and rb - 87…
$85.47\ \text{amu}$
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part a lead consists of four naturally occurring isotopes. calculate th…
$208.2$ amu
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what is the atomic symbol of another isotope of gold with 116 neutrons?…
$^{195}_{79}Au$ $^{200}_{80}Hg$
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6 reflections and conclusions how can you distinguish between a physica…
6. Physical change: no new substance formed, only physical properties change. Chemical change: new substance with different chemical properties formed. 7. Physical change example:…
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the density of nickel is 8.9g/cm3. the sample weighs 500g. what is the …
56.1cm3
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physical and chemical changes - 7.6c 3 questions look back at the list …
3. Cutting paper is a physical change. 4. None of copying, cutting, or pasting paper are chemical changes. 5. No information about simulation experiments provided to answer.
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draw the molecular orbital (mo) electron diagram for the be₂⁻ molecular…
The molecular - orbital diagram will have the following orbitals filled: $\sigma_{1s}$ (2 electrons), $\sigma_{1s}^*$ (2 electrons), $\sigma_{2s}$ (2 electrons), $\sigma_{2s}^*$ (…
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experiment what did you observe in the experiment? (use words from the …
| Experiment | What Did You Observe in the Experiment? (Use words from the clue chart.) | Was This a Physical or Chemical Change? | |--|--|--| | Boiling water | Bubbles, water vap…
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physical changes clue words chemical changes clue words - cutting - mix…
Boiling water: Change of state, boiling; Physical change Rotting banana: Odor, color change; Chemical change Mixing baking soda and vinegar: Fizzing; Chemical change
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draw the molecular orbital (mo) electron diagram for the h₂²⁻ molecular…
Draw two boxes labeled $\sigma_{1s}$ (lower energy) and $\sigma_{1s}^*$ (higher energy). In the $\sigma_{1s}$ box, place two electrons with opposite spins ($\uparrow\downarrow$) a…
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26. match the element with the number of valence electrons they have. d…
Phosphorus (P) $\to$ 5 Aluminum (Al) $\to$ 3 Calcium (Ca) $\to$ 2 Sulfur (S) $\to$ 6 Potassium (K) $\to$ 1 Iodine (I) $\to$ 7
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physical and chemical changes - 7.6c 1 procedure your teacher gives you…
Folding, Tearing, Crumpling, Cutting, Burning
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25. match the element with the ionic charge they will form. draggable i…
Phosphorus (P) → - 3 Calcium (Ca) → + 2 Potassium (K) → + 1 Sulfur (S) → - 2 Aluminum (Al) → + 3 Iodine (I) → - 1
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24. how many valence electrons does the element below have? type a resp…
4
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a number of substances and their chemical formulas are listed below. ch…
carbon monoxide (CO), glucose ($C_6H_{12}O_6$)
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20. how many energy levels does calcium have? type a response 21. how m…
20. 4 21. 4 22. 2
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19. which element would have the largest radius?
Sr (Strontium)
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19. which element would have the largest radius?
Cs
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18. which element would have the smallest radius?
Ne
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16. which alkali metal would have the largest atomic radius? type a res…
16. Francium (Fr) 17. Beryllium (Be)
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14. which transition metal has the smallest atomic radius? (put the sym…
14. Sc 15. He
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13. the shaded elements are referred to as the ______________
Transition metals
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study the following sketch of a molecular orbital (mo) in a homonuclear…
| Property | Answer | |--|--| | Write the symbol for this MO | $\pi^{*}$ | | Is this a bonding or antibonding MO? | antibonding | | What is the energy of this MO, compared to the …
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11. what is the name of this family? type a response
Alkaline - earth metals
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28. sulfur trioxide is known to be planar with all the oxygen atoms equ…
e) 1, 2, and 3 ### 29.
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12. what is the name of this family? type a response
Noble - gas family
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9) the shorter the fatty acid chain, the more liquid the fatty acid. tr…
9. True 10. True 11. False 12. True
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1) all of the following are true about lipids except: they dissolve eas…
1. They dissolve easily in water. 2. 20-35
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what is the hybridization of the central atom in the phosphorus tetrabr…
$sp^{3}d$
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answer the questions below about the highlighted atom in this lewis str…
In how many sigma bonds does the highlighted atom participate? 4 In how many pi bonds does the highlighted atom participate? 0 What is the orbital hybridization of the highlighted…
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23. carbon dioxide reacts with an aqueous solution of sodium hydroxide …
23. b) $sp$ to $sp^2$ 24. b) $sp^2$ to $sp$ 25. e) no change 26. d) an $sp^3d$ hybridized fluorine atom 27. d) 1, 2, and 3
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consider the carbon tetrachloride (ccl4) molecule. what is the central …
What is the central atom? Enter its chemical symbol: C How many lone pairs are around the central atom? 0 What is the ideal angle between the carbon - chlorine bonds? 109.5 Compar…
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answer the questions in the table below about the shape of the sulfur h…
How many electron groups are around the central sulfur atom? 6 What phrase best describes the arrangement of these electron groups around the central sulfur atom? Octahedral
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post-lab q13 consider the molecule you constructed within the phet simu…
A. CH₄
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answer the questions in the table below about the shape of the sulfur t…
How many electron groups are around the central sulfur atom? 5 What phrase best describes the arrangement of these electron groups around the central sulfur atom? Trigonal bipyram…
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what is the hybridization of the central atom in the phosphodichloride …
$sp^{3}$
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extra practice: complete the following table... | compound | elements p…
| COMPOUND | ELEMENTS PRESENT IN COMPOUND & HOW MANY OF EACH | TOTAL NUMBER OF ATOMS IN COMPOUND | |--|--|--| | NaOH | Na: 1, O: 1, H: 1 | 3 | | AlCl₃ | Al: 1, Cl: 3 | 4 | | Mg₃(P…
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tag all the carbon atoms with pi bonds in this molecule. if there are n…
The two carbon atoms that form the triple - bond ($C\equiv C$) should be tagged.
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answer the questions in the table below about the shape of the phosphor…
How many electron groups are around the central phosphorus atom? 4 What phrase best describes the arrangement of these electron groups around the central phosphorus atom? Tetrahed…
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answer the questions in the table below about the shape of the iodite (…
How many electron groups are around the central iodine atom? 4 What phrase best describes the arrangement of these electron groups around the central iodine atom? tetrahedral
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decide whether each molecule or polyatomic ion is polar or nonpolar. if…
| molecule or polyatomic ion | polar or nonpolar? | atom closest to negative side | | ---- | ---- | ---- | | $CH_2O$ | polar | O | | HI | polar | I | | $SiF_4$ | nonpolar | |
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classify each reaction below as either formation, decomposition, replac…
6. Single - replacement 7. Decomposition 8. Single - replacement
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consider the molecule you constructed within the phet simulation, ident…
A. $CH_4$
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kenneth just bought a running watch that has gps technology. what does …
C. global positioning system
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protons, neutrons, and electrons for an atom. i can determine the numbe…
a. Carbon b. Atomic number c. Mass numbers d. Protons: 6, Neutrons: 6 e. Protons: 6, Neutrons: 7 f. Protons: 6, Neutrons: 8
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1. here are three isotopes of an element: (^{12}_6c), (^{13}_6c), (^{14…
| Isotope | Atomic # | Mass # | # of protons | # of neutrons | # of electrons | |---|---|---|---|---|---| | $^{12}C$ | 6 | 12 | 6 | 6 | 6 | | $^{13}C$ | 6 | 13 | 6 | 7 | 6 | | $^{…
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18. how does the endocrine system transmit information and interact wit…
18. The endocrine system uses hormones as chemical messengers, secreted into the bloodstream, and interacts with the nervous system via feedback loops. 19. Adrenaline: Adrenal gla…
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identify each example of chemical weathering
Both the cave formation and the rock with holes are examples of chemical weathering. The cave is formed through the reaction of acidic water with limestone, and the holes in the r…
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is this image an example of chemical weathering or mechanical weatherin…
chemical weathering
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9) the sugar that occurs naturally in fruits is galactose. true false 1…
9) B. False 10) A. True 11) B. False
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question: what factors affect the radius of an atom? 1. predict: how do…
# Explicación paso a paso: ## Paso 1: Identificar los factores que afectan el radio atómico Los factores que afectan el radio atómico son el número de niveles de energía y la atra…
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27. one type of organic molecule can be converted to another type of or…
C. The absorption of infrared radiation causes the transition to a higher vibrational level associated with the stretching of the carbonyl. ### 28.
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question 20 a 75 g solution containing 2.4 ml of ethanol with a density…
$3.52$
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25. which of the following best explains what happens as photons of vis…
25. D. Certain electrons in the dye molecule move to a higher energy level, with the difference in energy between the lower and higher energy levels being the same as the energy o…
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question 19 the mass percent of a solution containing 25 g in 125 g of …
$16.7$
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what is the molarity of a solution containing 1 g kno₃ in 202 ml? add y…
0.049 M
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draw the molecular orbital (mo) electron diagram for the he₂⁻ molecular…
Draw a diagram with two horizontal lines representing the $\sigma_{1s}$ and $\sigma_{1s}^*$ molecular orbitals. Label the $\sigma_{1s}$ orbital at a lower energy level and the $\s…
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23. a student adds a 1g sample of an unknown, brittle solid to distille…
23. A. The increase in conductivity indicates that the unknown is an ionic solid that dissociates into ions when it dissolves in water. 24. A. Diagram 1, because strong ion - dipo…
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slide: medications and the brain what chemical do medications stimulate…
Neurotransmitters (e.g., dopamine, serotonin)
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steps for balancing equations __hgo→__hg + __o₂ hg - 1 o - 1 hg - 1 o -…
$2HgO ightarrow 2Hg + O_2$; $N_2+3H_2 ightarrow 2NH_3$; $2KClO_3 ightarrow 2KCl + 3O_2$; $2KBr+Cl_2 ightarrow 2KCl + Br_2$; $2CO+O_2 ightarrow 2CO_2$; $4C + S_8 ightarrow 4CS_2$; …
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the diagram above shows thin - layer chromatograms of the same mixture …
21. C 22. C
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chemical equation: 6co₂ + 6h₂o → c₆h₁₂o₆ + 8o₂. list the reactants: how…
List the Reactants: \(6CO_2\), \(6H_2O\) How many of each atom is present in the Reactants? C: 6, H: 12, O: 18 List the Products: \(C_6H_{12}O_6\), \(8O_2\) How many of each atom …
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question,choice a,choice b,choice c 1. this is the process by which one…
(1) C. both A & B (2) B. product (3) C. coefficient (4) A. reactants (5) B. chemical equation (6) B. products (7) A. chemical formula (8) B. subscript (9) C. \(C_{6}H_{12}O_{6}\) …
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question 14 blank 1 grams of caco₃ is in 4 l of a 3.4 m mgoh solution b…
Insufficient data ### Question 15
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complete the solubility table.
The table is already completed correctly as shown in the problem statement with $Na^{+}$ compounds being soluble, $Ag^{+}$ compounds being insoluble for $Br^{-}$, $OH^{-}$, $CO_{3…
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7 how can people reduce water pollution? choose two. use as little wate…
Use more reusable items, Use eco - friendly products
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the molarity of a 1.5 l solution containing 4 g of mgbr₂ is blank 1 m. …
0.014
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draw the molecular orbital (mo) electron diagram for the ne₂ molecule. …
A complete molecular orbital diagram for $Ne_2$ would have the following orbitals filled in order of increasing energy: $\sigma_{1s}$ with 2 electrons, $\sigma_{1s}^*$ with 2 elec…