Chemistry
Chemical reactions, stoichiometry, molecular structures, and element properties.
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example 6 - 13: use your knowledge of intermolecular forces to predict …
\(CH_3CH_2CH_2OH(l)\) has the higher boiling point.
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grade 11 chemistry sch3u test 1. matter and chemical bonding name: arno…
1. e. Cl 2. c. are composed of only two kinds of monatomic ions 3. a. can form more than one ion, each with its own charge 4. b. diphosphorus tetraiodide 5. b. Co(s) 6. a. 1 lone …
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c) if the bond is covalent identify it as polar or non - polar. (hint: …
a) H:O:H (with one more H attached to O via a coordinate bond, O has one lone pair) .. H b) O=S=O (with a third double-bonded O, trigonal planar, resonance) || O (Note: Electron d…
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in order for the chemical reaction in batteries to continue working, wh…
C. electrons (assuming the options are labeled as A. velocity, B. chemicals, C. electrons; if labels differ, adjust but the correct option text is "electrons")
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6- but, if the accused person opened the other door, there came forth f…
If the accused opened the other door, a king - selected suitable lady emerged, and he was immediately married to her as an innocence reward, with the king’s scheme ignoring the ac…
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driving a car or truck under many conditions is a fairly safe activity.…
Skydiving without proper gear, drunk driving, rock climbing without safety harnesses, handling hazardous chemicals unsafely.
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8. the following reaction represents the complete combustion of hexane,…
a. \( 1.18\times10^{7}\text{ J}\) b. \( 2.10\text{ kg}\)
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7. what is the standard molar enthalpy of combustion for the following …
The standard molar enthalpy of combustion of \(C_2H_2(g)\) is \(-1250\space kJ/mol\)
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5. the combustion of methane, ch4, releases 890.4 kj/mol. ch4(g) + 2 o2…
a. \( 2176.792\ \text{kJ}\) b. \( 556.5\ \text{kJ}\)
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how does an atom change if all of its electrons are removed? the atoms …
The atom becomes positively charged.
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what is the number at the end of an isotopes name? atomic number neutro…
C. mass number
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jerome is learning how the model of the atom has changed over time as n…
Y, X, Z, W
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atom a and atom b have the same number of protons, but they do not have…
A. Atom A and Atom B are isotopes of the same element
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in which orbitals would the valence electrons for selenium (se) be plac…
s orbital and p orbital
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an atom of the element zinc has an atomic number of 30 and a mass numbe…
A. 30
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this is how sodium appears in the periodic table. the arrow is pointing…
atomic mass (the option corresponding to "atomic mass")
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while looking at xenon (xe) on the periodic table, a student needs to f…
A. directly up
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the elements in group 17 of the periodic table are all called halogens.…
D. number of valence electrons
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who is known as the \father of modern chemistry\ because he first organ…
Antoine Lavoisier
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who described atoms as small spheres that could not be divided into any…
B. Dalton
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when an atom that has no charge loses two electrons, it becomes a posit…
A. positive ion.
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scientists in a lab are working with two different samples of the eleme…
the mass number
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which statement best describes how electrons fill orbitals in the perio…
A. Electrons fill orbitals in order of their increasing energy from left to right.
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the first model of the atom was developed through scientific experiment…
thinking about the smallest particles of matter without experimenting.
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what are the two parts of an atom? the nucleus and the proton cloud the…
D. the nucleus and the electron cloud (assuming the last option is labeled D; if labels are A - D as per order, the last option is D with text "the nucleus and the electron cloud")
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how many valence electrons does aluminum (al) have available for bondin…
3 (corresponding to the option "3")
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33. given the information $$ mathrm { n } _ { 2 } mathrm { o } _ { 4 } …
The second reaction's \(\Delta H_{r}^{\circ}\) value is incorrect. The correct \(\Delta H_{r}^{\circ}\) for \(NO_{2}(g)\to\frac{1}{2}N_{2}O_{4}(g)\) is \(-28.6\space kJ\) (not \(-…
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reaction 10d: previous products with additional hydrochloric acid coppe…
$\boldsymbol{\text{Cu}^{2+}(aq) + 4\text{Cl}^-(aq) = \text{[CuCl}_4\text{]}^{2-}(aq)}$
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6.1 a certain amount of nahco₃(s) was put into a vacuum container, then…
### 6.1 Solution (Using Phase Rule Concepts) #### Explanation: To solve for \( R', C, P, F \) for the reaction \( \boldsymbol{2\ NaHCO_3(s) = Na_2CO_3(s) + H_2O(g) + CO_2(g)} \): …
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read the excerpt from \a modest proposal\a very worthy person, a true l…
Swift uses irony when he says the person with whom he discussed his plan is "very worthy" and "a true lover of this country."
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write in the charge behind each ion below that does not have a charge s…
1. Ions: Li⁺, O²⁻; Formula: Li₂O; Name: Lithium oxide 2. Ions: Ag⁺, OH⁻; Formula: AgOH; Name: Silver hydroxide 3. Ions: Mg²⁺, SO₄²⁻; Formula: MgSO₄; Name: Magnesium sulfate 4. Ion…
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question 25 (4 points) the equilibrium constant for reaction 1 is k. th…
a) $1/K^{2}$
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question 24 (4 points) δs is positive for the reaction ________. o a) 2…
d) \( \text{BaF}_2 \, (s) ightarrow \text{Ba}^{2+} \, (aq) + 2\text{F}^- \, (aq) \)
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unit 10 final exam as the temperature of a reaction is increased, the r…
b) reactant molecules collide more frequently and with greater energy per collision
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the addition of hydrofluoric acid and ___ to water produces a buffer so…
a) NaF
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question 21 (4 points) which of the following substances is more likely…
b) \( \text{CBr}_4 \)
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question 20 (4 points) which of the following is the weakest acid? a) h…
d) HCN ($K_a = 4.9 \times 10^{-10}$)
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the rate law for a reaction is rate =kab. which one of the following st…
a) The reaction is first order overall.
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question 18 (4 points) consider a pure crystalline solid that is heated…
d) vaporizing the liquid
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question 17 (4 points) the ka of hydrofluoric acid (hf) at 25°c is 6.8 …
b) 1.76
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question 16 (4 points) which one of the following is true in an acidic …
a) $[\ce{H3O+}] > [\ce{OH-}]$
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question 16 (4 points) which one of the following is true in an acidic …
a) $[\ce{H3O+}] > [\ce{OH-}]$
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question 15 (4 points) a reversible process is one that ________. a) ca…
a) can be reversed with no net change in either system or surroundings
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question 13 (4 points) phosphorus trichloride and phosphorus pentachlor…
a) 7.99
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a reaction that is spontaneous as written____ ○ a) is very rapid ○ b) w…
b) Will proceed without outside intervention
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question 11 (4 points) according to the following equation, what is the…
c) 0
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question 10 (4 points) the second law of thermodynamics states that ___…
c) for any spontaneous process, the entropy of the universe increases
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question 9 (4 points) the equilibrium expression for kp for the reactio…
a) \( \frac{3PO_2}{2PO_3} \)
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question 9 (6 points) the equilibrium expression for kp for the reactio…
\(\boldsymbol{\frac{(P_{O_2})^3}{(P_{O_3})^2}}\) (matching option with this form, e.g., if option a is \(\frac{3P_{O_2}}{2P_{O_3}}\) no, correct is \(\frac{(P_{O_2})^3}{(P_{O_3})^…
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question 8 (4 points) what is the molality of a 10.0% (by mass) aqueous…
b) 3.05
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question 7 (4 points) if the rate law for the reaction 2a + 3b → produc…
b) \( k[\text{A}]^2[\text{B}]^3 \)
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question 6 (4 points) which reaction produces a decrease in the entropy…
b. \( \text{Na (s)} + \frac{1}{2} \text{Cl}_2 \text{(g)} ightarrow \text{NaCl (s)} \)
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question 5 (4 points) which of the following expressions is the correct…
c) \([NO_2]^2 / [N_2O_4]\)
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question 4 (4 points) which one of the following processes produces a d…
a) freezing of Fe(l) into Fe(s)
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what is the principle reason for low solubility of nacl in benzene (c₆h…
c) weak solvation of $\ce{Na+}$ and $\ce{Cl-}$ by $\ce{C6H6}$
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which one of the following is most soluble in water? a) ch₃oh b) ch₃ch₂…
a) $CH_3OH$
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after a computer has joined a domain controller, you will find the comp…
Active Directory Users and Computers
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the answer to the calculation (21 + 10.8 + 130.363 + 24.5467) should ha…
2) 0
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when zn metal was dipped in a solution of acid, it released hydrogen ga…
2) I, II and III
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17. use the iupac rules to name the following structures. a. $ch_{3}ch …
a. 4 - methyl - 2 - hexene b. 2 - isopropyl - 7 - methyl - 5 - octene
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additional practice 8. use the iupac rules to name the following struct…
a. 2,5 - dimethylheptane b. 2,2,4 - trimethylpentane c. 3 - ethyl - 2,6,8 - trimethylnonane
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question 13 (1 point) listen the reaction of magnesium oxide when heate…
3) Oxidation - reduction, combustion and gas - forming
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question 1 ___________ is the highly addictive chemical found in tobacc…
C. Nicotine
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question 2 why are the flavors in e-cigarettes specifically dangerous? …
A. The flavors have chemicals in them that are dangerous to inhale
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data tables required: note: the enthalpy of formation of butane (c₄h₁₀)…
The enthalpy change ($\Delta H^{\circ}$) of the reaction is $\boldsymbol{-89.0\ kJ}$, and the reaction is exothermic in the forward direction. ### Part (b)
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follow the steps provided by your teacher to complete each bond. ionic …
Chemical formula is $MgBr_2$ (Lewis structures: Mg with 2 dots, Br with 7 dots; Mg loses 2 e⁻ to 2 Br atoms, Mg becomes $Mg^{2+}$, each Br becomes $Br^-$) ### Ionic Bonds (2) Pb +…
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27 sep construct an explanation explain whether the formula cuo can be …
The formula \( \text{CuO} \) can be used to represent copper(II) oxide (since \( \text{Cu}^{2+} \) and \( \text{O}^{2-} \) balance as \( 1(+2) + 1(-2) = 0 \)), but not copper(I) o…
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uranium decays over time as each of its atoms splits into smaller parti…
C. Uranium in Gabon, Africa, is more likely to decay quickly than in other parts of the world.
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unit 4: periodic trends directions: answer each question completely. in…
1. Period trend: Arrow from right to left; Group trend: Arrow from top to bottom (on the periodic table outline). 2. Period trend: Arrow from left to right; Group trend: Arrow fro…
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4 if you were looking to decrease the amount of carbon emissions associ…
freshly preparing a vegan dish with local, organic vegetables and fruits
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2 which of the following factors contribute the most to an individuals …
eating processed food that is shipped across the country
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dolphins frequently attack fishing nets for food, causing fishers to lo…
A. prove that dolphins are not physically sensitive to capsaicin.
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2.3 elements and compounds 52. how could you distinguish an element fro…
To distinguish an element from a compound: An element is a pure substance composed of only one type of atom (e.g., sodium, $\ce{Na}$ has only sodium atoms). A compound is a pure s…
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a chemist carefully measures the amount of heat needed to raise the tem…
\boxed{209}
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use the references to access important values if needed for this questi…
(for the solubility part): soluble (For the precipitation reaction, using the lowest coefficients, the reaction is \( \boldsymbol{(\text{NH}_4)_2\text{CO}_3(aq)+\text{Ca(NO}_3\tex…
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which of the following has the lowest number of unshared electrons arou…
SF₆
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for each of the salts on the left, match the salts on the right that ca…
### Part 1: Matching Copper(II) Sulfide (CuS) To directly compare solubilities using \( K_{sp} \), salts must have the same dissociation stoichiometry (same number of cations and …
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consider these compounds: a. pbf₂ b. ni(oh)₂ c. fes d. cas complete the…
First blank: CD Second blank: AB
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use the references to access important values if needed for this questi…
C. Low ### Second Sub - Question (Solubility of Chromium(III) Phosphate in Water)
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chapitre 1.6 : la conservation de la m... quelle masse de matière est o…
47 g 8 g 100 g 7 g
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complétez les équations suivantes inscrire seulement le bon chiffre (mê…
2 3 1
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7. on fait réagir deux substances selon la réaction: a + b ---> c + d 5…
C. 3 g
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5. on peut transformer un atome en un autre au cours dun changement chi…
5. Faux 6. Impossible
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vrai ou faux ? 1. la masse est conservée au cours dun changement physiq…
1. Vrai 2. Faux 3. Vrai 4. Faux
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in this lab, you will start off by calculating the number of moles of a…
\( 0.0066 \, \text{mol} \)
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the boiling point of water at 1 atm is 100°c and the boiling point of e…
A. Ethanol
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use the references to access important values if needed for this questi…
for the solubility part: soluble
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in this lab, you will determine the vapour pressure (p) of water at var…
$\approx25.8\ kJ/mol$ (or more precisely, using $3105\times8.314 = 25815.07\ J/mol=25.82\ kJ/mol$)
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the value of the solubility product constant for silver bromide is writ…
\(AgBr(s) ightleftharpoons Ag^+(aq) + Br^-(aq)\)
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the value of the solubility product constant for silver bromide is writ…
The reaction is $\boldsymbol{\text{AgBr}(s) ightleftharpoons \text{Ag}^+(aq) + \text{Br}^-(aq)}$ and the $K_{sp}$ value for silver bromide is $5.3 \times 10^{-13}$ (this is the kn…
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write the dissolution reaction for manganese(ii) bromide in water. be s…
A. Soluble ### Part 3: Equilibrium Constant for the Reaction
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a 24.2 ml sample of 0.275 m ammonia, nh3, is titrated with 0.293 m nitr…
$\boxed{1.28}$
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a 24.2 ml sample of 0.275 m ammonia, nh3, is titrated with 0.293 m nitr…
\boxed{1} (or more precisely ~1.3, but based on the problem's context, 1 is acceptable)
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a 27.1 ml sample of 0.348 m dimethylamine, (ch3)2nh, is titrated with 0…
\(10.73\)
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question 5 (1 point) ✓ saved listen gaseous methane (ch₄) reacts with g…
3) CH₄(g) + 2O₂(g) → CO₂(g) + 2H₂O(g)
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how did scientific research affect the widespread use of ddt in control…
C. Research showed that DDT accumulated as poison in other wildlife, so the U.S. Environmental Protection Agency was established.
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an aqueous solution contains 0.23 m nitrous acid. one liter of this sol…
0.06 mol $\ce{Ba(OH)_2}$, 0.24 mol $\ce{KNO_2}$
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an aqueous solution contains 0.23 m nitrous acid. one liter of this sol…
0.06 mol $\ce{Ba(OH)_{2}}$
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13. what is the formula and specific charge on the silicite ion, if sil…
$\text{SiO}_2^{2-}$
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which two statements represent scientific research problems rather than…
Studying how wildlife is affected by pollution, Comparing root structures in different kinds of plants