化学
化学反応、化学量論、分子構造、元素の性質。
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which of the following elements has a valence of 3? answer options: sel…
A. Aluminum
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there are 38 ____ metals in groups 3 through 12 of the periodic table.
transition
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____ series members are radioactive metallic elements. answer input: sp…
actinide
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____, a powerful nonmental thats used to bleach wool and straw, is a br…
Sulfur
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elements with features of both metals and nonmetals are called _____. a…
B. metalloids
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if all of the atoms in a molecule of a substance are alike, then the su…
element
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marble and water are both chemical compounds because they consist of at…
elements
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which of the following physical properties indicates the shininess of a…
Luster
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located in the last column of the periodic table, noble gases are the l…
stable outermost electron shells.
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atoms are made up of tiny particles called protons, neutrons, and elect…
center of an atom.
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help wanted! science career research project part 1: research a career …
This is a research project template for a science career. To complete it, you can choose a specific science career (e.g., Biologist, Chemist, Physicist, etc.) and then research th…
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16. c₃h₈ + o₂ → co₂ + h₂o
\( \boldsymbol{\ce{C3H8 + 5O2 -> 3CO2 + 4H2O}} \)
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if the molecules of a body move ____ to the direction in which a wave t…
parallel
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the distance between the two nearest molecules that are in phase with e…
wavelength
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exam lesson name: states of matter exam number: 700698rr ▶ exam guideli…
A. A change in a gas's pressure results in a more significant change in volume than would occur in a liquid.
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exam lesson name: states of matter exam number: 700698rr ▶ exam guideli…
C. The change in pressure is transmitted equally throughout the entire liquid.
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exam lesson name: states of matter exam number: 700698rr exam guideline…
D. $\text{cm}^3$
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exam lesson name: states of matter exam number: 700698rr exam guideline…
B. The energy of particles
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exam lesson name: states of matter exam number: 700698rr exam guideline…
B. saturation point.
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exam lesson name: states of matter exam number: 700698rr exam guideline…
D. The red liquid is the least dense.
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exam lesson name: states of matter exam number: 700698rr exam guideline…
B. vapor
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exam lesson name: states of matter exam number: 700698rr ▶ exam guideli…
C. The heat absorbed or lost by a substance while it's changing state
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question 4 of 20 : select the best answer for the question. 4. a unique…
D. less
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exam lesson name: states of matter exam number: 700698rr exam guideline…
B. Water
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which of the following is in a liquid state at temperatures between −10…
B. Alcohol
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exam lesson name: energy conversions exam number: 700697rr exam guideli…
A. It would take more energy to increase the temperature of methyl alcohol.
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exam lesson name: energy conversions exam number: 700697rr exam guideli…
D. Ammonia
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____ is formed by heating bituminous coal in an oven until all of the v…
coke
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before combustion can occur, the fuels temperature must be raised to th…
D. ignition
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when the molecules of a body move less rapidly, heat energy in the body…
A. reduced
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the temperature of a body depends on the ______. answer options: select…
average velocity of the body’s molecules
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downloaded from stanmorephysics.com grade 11 - ncs question 2 (start on…
A limiting reactant is a reactant in a chemical reaction that is completely consumed, thereby limiting the amount of product formed as the reaction ceases when this reactant is ex…
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23. what is the range of hold that a styling product might have on hair…
To solve the matching problem for styling aids and their descriptions, we analyze each option: ### Step 1: Analyze "Also known as mousse" The description "Also known as mousse" ma…
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in the following diagrams, elements are represented by x and z, which f…
B. \( \boldsymbol{Z:\overset{..}{X}:Z} \)
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3 mark for review lewis diagrams of molecules of three different hydroc…
D. The strongest carbon - to - carbon bond occurs in molecule 3.
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(c) a graph of potential energy versus internuclear distance for two cl…
To sketch the curve for $Br_2$: 1. **Shape**: Maintain the same general curve shape (decreasing to a minimum, then increasing) as the $Cl_2$ curve. 2. **Equilibrium Distance**: Sh…
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7. which of the following is a precious metal commonly used in jewelry …
a. Platinum
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in a group of water molecules, hydrogen bonds form between ______. a tw…
d. the oxygen atom in one molecule and a hydrogen atom in another molecule
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what name is given to the bond between different water molecules? a ion…
b. hydrogen
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question 3 (1 point) a polar covalent bond ______. a shares electrons e…
d. results from the unequal sharing of electrons
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question 1 (1 point) an atoms reactivity is determined by its ______. a…
d. electron configuration
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when comparing different ionic compounds, the one with the ions of grea…
smaller
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which of the following would be expected to have the lowest melting poi…
KI
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non-polar molecule, polar molecule, xef₂
$\ce{XeF2}$ is a non - polar molecule, so it should be placed in the "Non - Polar Molecule" category.
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question: what agricultural method did the aksumites adapt that involve…
Terrace farming
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what is the molecular geometry of the following? image of a molecular m…
B. Tetrahedral
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polar bonds non-polar molecule non-polar bonds polar molecule so₂ selec…
- polar bonds - Polar molecule
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based on formal charge arguments, which molecule is the more appropriat…
The middle structure (with \( \text{H}_2\text{N}-\text{O}-\text{H} \) and a lone pair on N) is the more appropriate structure.
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this carbon atom has... options: sp³ hybridization (yellow), sp² hybrid…
The carbon atom has \( \boldsymbol{sp^2} \) hybridization (corresponding to the "sp² hybridization" option).
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what 3-d vsepr shape does this molecule exhibit? options: linear, trigo…
trigonal pyramidal (assuming the molecule has 3 bonding regions and 1 lone pair, like \(NH_3\)) or if it's \(CH_4\) - tetrahedral, \(BF_3\) - trigonal planar, \(CO_2\) - linear. B…
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what is the molecular geometry of the following? square planar, tetrahe…
B. Tetrahedral
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identify the hybridization of the highlighted carbon present in 2-butyne
\( \text{sp}^3 \) (the orange option)
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draw the lewis structure for bei₂. then compare your drawing to the ans…
The correct option is the purple - colored card (with the structure showing Be in the middle, single bonds to two I atoms, and 3 lone pairs on each I atom). If we assume the purpl…
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which of the following images represents a trigonal bipyramidal molecul…
The image with the green border (the top - most image among the four) represents a trigonal bipyramidal molecular geometry.
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choose the ionic compound with the greater magnitude of lattice energy.…
\( \text{CaCl}_2 \)
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h−c≡c−h(g) + 2hi(g) → (h₃c−c−i with h atoms) (g) using the table of ave…
-217
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what is the shape of the following molecular structure? options: linear…
B. Trigonal planar
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which molecule exhibits resonance? co₂ o₃ becl₂ nf₃
\( \text{O}_3 \) (Ozone) exhibits resonance.
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which statements describe iambic pentameter as it is used in shakespear…
A. Each line contains five metrical feet, E. In a group of two syllables, the second is stressed
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which molecule exhibits resonance? options: co₂, o₃, becl₂, nf₃
\( \text{O}_3 \) (the molecule in the blue box)
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if a molecule contains polar bonds, the molecule may or may not be pola…
True
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what is the molecular shape of the following? options: trigonal bipyram…
Octahedral (the option with text "Octahedral")
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what is the correct lewis structure for ammonia, nh₃?
The correct Lewis structure for \( \text{NH}_3 \) is the top - most (yellow - bordered) structure, which shows nitrogen (\( \text{N} \)) bonded to three hydrogen (\( \text{H} \)) …
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what is the formal charge on the bromine atom in this lewis dot structu…
\(+1\)
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apply the vsepr model to xef₄. which of the following molecular shapes …
B. Square planar
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if the energy needed to break bonds is less than the energy released wh…
the reaction will be exothermic (the option with the teal background, assuming the typo - free correct option is "the reaction will be exothermic")
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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 formal charge of phosphorus in the lewis structure shown he…
0
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what is the molecular shape of the following? see-saw tetrahedral bent …
Tetrahedral
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the hybridization of the carbon present in formaldehyde, ch₂o, is image…
\(sp^{2}\)
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what is the molecular geometry of h₂s? lewis structure: h—s—h with two …
The molecular geometry of \(H_2S\) is bent. So the correct option is the one labeled "bent".
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choose the ionic compound with the higher boiling point.
NaCl (the ionic compound with the higher boiling point is NaCl)
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what is the molecular geometry? options: trigonal planar, linear, trigo…
Trigonal Pyramidal
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which of the following illustrations shows a trigonal planar geometry?
The illustration with the green border (the top - most one) shows a trigonal planar geometry.
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which of the following statement(s) applies to the carbonate ion, illus…
- carbonate ion exhibits resonance - all the carbon - oxygen bond lengths in carbonate are the same
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what molecular geometry has bond angles of 109.5°? options: tetrahed ra…
tetrahed ral (assuming it's a typo for tetrahedral)
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pre-lab 1 question 10 4.75 points homework • unanswered • due today, 1:…
# Explanation: ## Step1: Calculate the mean The mean ($\bar{x}$) is calculated by summing all the values and dividing by the number of values. Given values: \( x_1 = 8.009 \, \tex…
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the bond angle for a tetrahedral geometry is ——. options (from image): …
The bond angle for a tetrahedral geometry is \(109.5^\circ\) (the orange - colored option with \(109.5^\circ\)).
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question clay used to make earthenware has a good ______: it is pliable…
C. plasticity
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molecular shape for xef₄ (hint: start with a lewis structure) square py…
square planar
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which of the following images represents a trigonal planar molecular ge…
The image with the teal border (the bottom - most image among the four) represents a trigonal planar molecular geometry.
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title = q2a8 consider the following processes: (i) making kool-aid™ by …
(i), (ii), and (v) (the last option in the list: (i), (ii), and (v))
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question 1 1 pts title = q1a4 which of the following scientific observa…
None of the above statements in and of itself proves that "Hydrogen an element" (the option with this text, as it's the correct reasoning that the other observations don't prove h…
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pre-lab 1 question 9 4.75 points homework • unanswered • due today, 1:3…
c. 2.000 g/cm³
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pre-lab 1 question 8 4.75 points homework • answered • due today, 1:30 …
b. 2.70 g/cm³
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question 4 if a molecule is polar, we would expect which of the followi…
A. It will form hydrogen bonds with water
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which part(s) of the molecule below can form hydrogen bonds with water?…
B, D (and potentially C depending on context, but B and D are more direct for H - bonding with water)
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title = q7a10 the temperature of a chemistry lab you are working in is …
158.1 g
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question 1 which functional groups are in the molecule below? molecular…
- A: Aryl halide (or Chloro group on aromatic ring, Haloarene) - B: Heterocyclic amine (Piperazine, Cyclic diamine) - C: Ether - D: Carboxylic acid (If we consider each labeled pa…
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current attempt in progress estimate δu for the following reaction usin…
-90 kJ/mol
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current attempt in progress we can describe the combustion of glucose, …
-945 kJ mol⁻¹ (corresponding to the option: -945 kJ mol⁻¹)
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view policies current attempt in progress estimate the reaction energy …
The reaction energy for the reaction \(H_2 + F_2 ightarrow2HF\) is \(\boldsymbol{- 542\space kJ/mol}\) (the negative sign indicates that the reaction is exothermic).
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rank the elements or compounds in the table below in decreasing order o…
For rank 2: D (the substance with Lewis structure \(C_2Cl_4\)), for rank 3: B (the substance with Lewis structure \(O = N - Cl\))
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rank the elements or compounds in the table below in decreasing order o…
1. A (\(CaCl_2\)) 2. B (\(ONCl\)) 3. D (\(C_2Cl_4\)) 4. C (\(Cl_2\))
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rank the elements or compounds in the table below in decreasing order o…
1. Highest boiling point: B (CaO) 2. Next highest: A (\(CH_3CH_2OH\) or the Lewis structure shown for A) 3. Next: D (the Lewis structure shown for D) 4. Lowest: C (CO)
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rank the elements or compounds in the table below in decreasing order o…
1. D 2. B 3. C 4. A (If selecting the next highest after D, choose B; after B, choose C; after C, choose A.)
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part 3 - thinking with the periodic table 7. what do the elements that …
D. Electron Energy Levels ### Question 10
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the first charter of virginia, 1606 also we do, for us, our heirs and s…
B. The development of representative democracy.
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the first charter of virginia, 1606 also we do, for us, our heirs and s…
A. The democratic ideals of the Enlightenment.
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the first charter of virginia, 1606 also we do, for us, our heirs and s…
C. The origins of democracy in the North American British colonies.