Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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5. choose all that apply. what are the two reactants? □ co₂(g) □ h₂o(g)…
\(O_2(g)\), \(C_4H_{10}(g)\) (the checkboxes for \(O_2(g)\) and \(C_4H_{10}(g)\) should be selected) ### Question 6
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3. choose the best answer. what phase of matter are all the compounds i…
A. gas ### Question 4:
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choose the best answers using the equation. $2\\ce{c4h10}(g) + 13\\ce{o…
B. 8 (assuming the options are labeled with letters, but based on the numbers, the correct coefficient is 8, so the option with 8 is the answer) ### Question 2
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match the items in the left column to the appropriate blanks in the sen…
The left interior N atom has \(\boldsymbol{\text{trigonal planar}}\) electron geometry and \(\boldsymbol{sp^2}\) hybridization. The right interior N atom has \(\boldsymbol{\text{t…
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label the structure of \\( \\ce{cocl2} \\), including overlapping orbit…
- For the Cl - C bonds (the two single bonds to Cl): \( \sigma: C(sp^2)-Cl(p) \) - For the C=O π bond (the side - by - side overlapping orbitals): \( \pi: C(p)-O(p) \) - For the C…
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given the lewis structure of co₂, the central carbon atom has lone pair…
- For \( \ce{CO2} \): lone pairs = zero, total electron groups = two, molecular geometry = linear. - For \( \ce{CCl4} \): lone pairs = zero, total electron groups = four, molecula…
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complete the sentences to explain why co₂ and ccl₄ are both nonpolar ev…
For \( \ce{CO2} \) blanks: zero, two, linear. For \( \ce{CCl4} \) blanks: zero, four, tetrahedral. The reason both molecules are nonpolar is best explained because the (polar bond…
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review link to access the section in your etext. part a determine wheth…
Polar: \( \text{IF}_3 \), \( \text{SO}_2 \), \( \text{BrF}_5 \), \( \text{SeF}_4 \) Nonpolar: (No molecules in the given set are nonpolar)
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determine whether each molecule is polar or nonpolar. drag the appropri…
Nonpolar: SiCl₄, SeF₆ Polar: CH₂F₂
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draw the lewis structure for co₂. draw the molecule by placing atoms on…
The Lewis structure of \( \ce{CO2} \) has a central C atom double - bonded to two O atoms (\( \ce{O=C=O} \)), with each O atom having two lone pairs of electrons. When drawing on …
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4. a vinegar sample contained 4.60% acetic acid. how many ml of 0.450 m…
\(42.6\space mL\)
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determine the idealized bond angles for each molecule. drag the items i…
- \( 90 \) degrees: (No molecules) - \( 120 \) degrees: (No molecules) - \( 180 \) degrees: \( \text{CS}_2 \) - \( 109.5 \) degrees: \( \text{PCl}_3 \), \( \text{SCl}_2 \), \( \te…
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determine the molecular geometry for each molecule. drag the items into…
- Linear: \( \text{CS}_2 \) - Trigonal planar: (No molecule here) - Tetrahedral: \( \text{CH}_3\text{F} \) - Trigonal Pyramidal: \( \text{PCl}_3 \) - Bent: \( \text{SCl}_2 \)
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determine the electron geometry for each molecule. drag the items into …
Linear: \( CS_2 \) Trigonal planar: None Tetrahedral: \( CH_3F \), \( PCl_3 \), \( SCl_2 \) Trigonal bipyramidal: None
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the measurement, 0.002006 g, has how many significant digits? a 1 b 2 c…
C. 3
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the measurement, 20600 molecules, has how many significant digits? a 1 …
C. 3
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3. will the concentration of the h₂c₂o₄ solution increase or decrease i…
The concentration of the $H_2C_2O_4$ solution will decrease. This is because oxalic acid ($H_2C_2O_4$) is photosensitive and decomposes when exposed to light. Storing it in a clea…
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the measurement, 206.0 c, has how many significant digits? a 1 b 2 c 3 …
D. 4
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3. will the concentration of the h₂c₂o₄ solution increase or decrease i…
The concentration of the \( \ce{H2C2O4} \) solution will decrease. This is because oxalic acid (\( \ce{H2C2O4} \)) is photosensitive and decomposes when exposed to light. Storing …
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missed this? watch kcv: vsepr theory, kcv: vsepr theory: the effect of …
(Part A): 6, 6, 0
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2. will the concentration of naoh solution increase or decrease if the …
The concentration of the NaOH solution will decrease. This is because NaOH reacts with carbon dioxide in the air (\(2NaOH + CO_2 = Na_2CO_3 + H_2O\)), reducing the amount of NaOH …
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2. will the concentration of naoh solution increase or decrease if the …
The concentration of the $\ce{NaOH}$ solution will decrease. This is because $\ce{NaOH}$ in the solution reacts with $\ce{CO_2}$ from the air (\(\ce{2NaOH + CO_2 = Na_2CO_3 + H_2O…
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will the concentration of solid naoh increase or decrease if the solid …
The concentration (purity) of solid NaOH will decrease. Because solid NaOH is hygroscopic (absorbs water from air) and reacts with atmospheric \(\boldsymbol{\text{CO}_2}\) (\(2\te…
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1. include the titration reactions of naoh and oxalic acid and naoh and…
\( \approx 42.6\ \text{mL} \)
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early movies had no sound, so audiences watched in silence. then, theat…
B. Piano players invited audiences to sing along to the music when the movie reels were being changed.
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unit test unit test complete jena is doing research for a presentation …
a. a university site showing the results of a study on which foods absorb chemicals
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12. a student says gases cannot be compressed because \particles dont s…
D. The claim is incorrect because particles are far apart and can be pushed closer. ### Question 13
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types of chemical reactions assessment 2kclo₃ → 2kcl + 3o₂ □ synthesis/…
Decomposition, Oxidation - Reduction (Redox) (the checkboxes for Decomposition and Oxidation - Reduction (Redox) should be selected)
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identify the use of jargon in the excerpt by sorting the words into the…
- Not Jargon: far door, eliminate - Jargon: hot side, air lock, chemical shower, decon cycle
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question 4 indicate the most important type of intermolecular attractio…
- Ethanol (\(C_2H_5OH\)) in water: hydrogen bonding - Toluene (\(C_7H_8\)) in benzene (\(C_6H_6\)): dispersion - \(CaCl_2\) in water: ion - dipole
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question 4 indicate the most important type of intermolecular attractio…
\(0.35\)
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combining. 9. filter the contents of the beaker, by using a funnel and …
1. \(n_{Cu}=\frac{2.477\ g}{63.55\ g/mol}\approx0.0390\ mol\) 2. \(n_{Fe}=\frac{2.322\ g}{55.85\ g/mol}\approx0.0416\ mol\) 3. \(\frac{n_{Fe}}{n_{Cu}}=\frac{\frac{2.322}{55.85}}{\…
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5 out of 10 true or false: foodborne illness occurs when food or water …
B. True
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3) what type of energy is being described? choose one. light/radiant ch…
chemical
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solar panels collecting sunlight and then using that energy to power ap…
radiant
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2) what type of energy is being described or used? thermal/heat chemica…
chemical
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which substance is a compound? ○ salt ○ phosphorus ○ sulfur ○ oxygen
A. salt
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question 2 (4 marks) in the lab you were asked to calculate a % differe…
% difference ≈ 2.32%, average volume ≈ 15.93 mL (Note: Validity check requires an expected range, which is not provided here.)
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which factor can decrease the rate of a chemical reaction? ○ low activa…
C. low temperature (assuming the options are labeled A: low activation energy, B: high pressure, C: low temperature, D: high concentration of enzyme)
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9. which part of the atom contributes most to its mass? a. electrons on…
B. Protons and neutrons
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8. where are electrons located in an atom? a. inside the nucleus b. in …
B. In the electron cloud surrounding the nucleus
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3. which statement best describes matter? a. anything that has mass onl…
C. Anything that has mass and takes up space
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circle the letter or highlight the correct answer. 1. what is the basic…
B. Atom
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question 3 in the sentence below, which contains items in a series that…
c. component and Department
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is this sentence in active voice or passive voice? in 1949, the u.s. fo…
active voice
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part a how many isomers exist for the alkane whose molecular formula is…
B. 2
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question 6 determine the number of sigma and pi bonds are in a molecule…
number of \(\sigma\) bonds: \(3\) number of \(\pi\) bonds: \(1\) ---
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question 4. h₂o a. ○ sp b. ○ sp² c. ○ sp³ d. ○ sp³d e. ○ sp³d² question…
Question 4: C. \(sp^{3}\) Question 5: D. \(sp^{3}d\)
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question 2 for each of the following molecules identify the hybridizati…
B. \( sp^{2} \) # Question 3
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how many grams of lif would be present in 575 ml of 0.750 m lif solutio…
D. 11.2
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match the type of bond to the illustration. fill in the blanks by selec…
1. pi bond formed from two p orbitals 2. sigma bond formed from one s and one p orbital 3. sigma bond formed from two p orbitals 4. sigma bond formed by two s orbitals
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a scientist is working with methane (ch₄) and butane (c₄h₁₀). which sta…
C. They are compounds made of the same two elements, but each contain different numbers of atoms.
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which molecule listed below is a polar molecule? nh₃ h₂o hcn all of the…
D. all of the compounds
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which of the following statements about acids are true? 1. an acid is u…
All of 1, 2, and 3
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which reaction is exothermic? ○ a reaction that absorbs energy from the…
a reaction that releases energy into the environment
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part a what is the concentration of the hydronium ions in a neutral sol…
1.0 ×10⁻⁷ M
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which of the following acids is a monoprotic, strong acid? carbonic aci…
hydrobromic acid
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how many ml of 0.218 m sodium sulfate react with exactly 25.34 ml of 0.…
B. 13.1
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the lewis model predicts that the formula of a compound formed between …
A. AlBr₃
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what is the formula for propene? c₃h₃ c₃h₆ c₃h₄ c₃h₈ none of the above
C. $C_3H_6$
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a neutralization reaction between koh (aq) and h₂so₄ (aq) would give wh…
D. H₂O (l) and K₂SO₄ (aq)
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which of the following is not an acid-base conjugate pair? - $\\ce{h2co…
H₂S and OH⁻
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a 90.0 g sample of naoh is dissolved in water and the solution is dilut…
none of the above
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which substance below has dipole-dipole forces? f₂ ch₄ h₂s co₂ none of …
H₂S
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how does a catalyst influence a chemical reaction? it speeds up or slow…
It decreases the amount of energy necessary for the reaction to proceed.
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a buffer solution is all of the following except: a solution that conta…
a solution that regulates pH because it is such a strong acid or base.
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what is the molecular geometry of sih₄? ○ bent ○ linear ○ tetrahedral ○…
tetrahedral
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a 35.0 ml sample of 0.225 m hbr was titrated with 42.3 ml of koh. what …
C. 0.186 M
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which compound below represents isopropyl alcohol? ○ ch₃ - ch₃ - oh - c…
The option with $\text{CH}_3-\text{CH}-\text{CH}_3$ (with OH attached to the middle CH)
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which is the name of $\\ce{c5h12}$? \\bigcirc n-butane \\bigcirc n-hexa…
D. n-pentane
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which substance is most likely to be miscible with water? ∘ br₂ ∘ chcl₃…
none of the above
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complete the rhyme scheme. a a b b c the great bare tree looked down an…
Line 1: A Line 2: A Line 3: B Line 4: B Line 5: C
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complete the rhyme scheme. a b b c c \who planted this old apple-tree?\…
First line (Who planted this old apple - tree?): A Second line (The children of that distant day): B Third line (Thus to some aged man shall say;): B Fourth line (And, gazing on i…
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(b) the diagram below represents a jiko when in use. study it and answe…
i. I. \(C + O_{2}\xrightarrow{\text{heat}}CO_{2}\) II. \(CO_{2}+C\xrightarrow{\text{heat}}2CO\) ii. Carbon monoxide burns (reacts with oxygen) to form carbon dioxide (\(2CO + O_{2…
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poetry notes ______ of literature that expresses ______ or ______ in a …
Literature (subfield of Arts)
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if we want to double the amount of water (h2o) we make. we want to make…
4 moles of hydrogen (or the option corresponding to 4 moles of hydrogen, e.g., if the option is "4 moles of hydrogen", then that is the answer)
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now lets say we want to double the amount of water (h2o) we make. we wa…
2 moles of oxygen
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if you wanted to make 2 moles of h2o (water) using hydrogen (h2) and ox…
1 mole oxygen
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if you wanted to make 36.0 grams of h2o (water) using hydrogen (h2) and…
B. 32.0 g O2
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now lets do some stoichiometry with some chemicals other than cookie in…
A. 4.0 g H2
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if you want to make 1 cookie how many eggs do you need? stoichiometry c…
B. \( \frac{1}{3} \) (a third) of an egg (assuming the options are labeled as A. 1 egg, B. \( \frac{1}{3} \) (a third) of an egg, C. 4 eggs)
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stoichiometry is a big word that describes a simple idea. stoichiometry…
C. amounts of substances that are involved in reactions. ### Second Sub - Question (Calculating Eggs for 12 Cookies)
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if you have one mole of h2o molecules (6.02 x 10^23 molecules of water)…
2 moles of H atoms (corresponding to the option: 2 moles of H atoms)
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so if you had 18 grams of h2o (water) how many moles of water molecules…
1 mole of H2O molecules
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what is the mass of h2o (water) according to the periodic table? hint: …
about 18 grams per mole
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what is the mass of hydrogen on the periodic table? atomic number 1 h s…
A. about 1 gram per mole (assuming the first option is labeled A, as per typical multiple - choice formatting with the first option being "about 1 gram per mole")
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what is the mass of oxygen atoms on the periodic table? atomic number 8…
The mass of oxygen atoms (atomic mass) on the periodic table is 15.999 grams per mole (or just 15.999 as the atomic mass value).
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so if you have 4 grams of helium how many moles of helium atoms do you …
1 mole
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write the complete ground-state electron configuration of cr²⁺. for mul…
\(1s^22s^22p^63s^23p^63d^4\)
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question 16 of 27 write the complete ground - state electron configurat…
\(1s^{2}2s^{2}2p^{6}\)
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write the complete ground-state electron configuration of be²⁺. for mul…
\(1s^{2}\)
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which state of matter has the greatest intermolecular attraction? gas s…
B. solid
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a chemist measures the enthalpy change $\\delta h$ during the following…
| reaction | ΔH | | --- | --- | | $\frac{1}{2}\text{NaCl}(s) ightarrow \frac{1}{2}\text{Na}(s) + \frac{1}{4}\text{Cl}_2(g)$ | 206 kJ | | $\text{Na}(s) + \frac{1}{2}\text{Cl}_2(g) …
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a cylinder is filled with 10.0 l of gas and a piston is put into it. th…
41.0 kPa
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what type of attractive force is the arrow pointing at in the molecule?…
intermolecular force
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what type of attractive force is the arrow pointing at in the molecule?…
intermolecular force
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what type of attractive force is the arrow pointing at in the molecule?…
intermolecular force
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what is the force that exists between atoms that are in different molec…
intermolecular force
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an arctic weather balloon is filled with 20.0 l of helium gas inside a …
19.0 L
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x. stop and think element with electron configuration # proton # electr…
A. shared; non - metal B. molecular