Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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(a) (i) write an equation for the reaction in which sulphur (iv) oxide …
- (i) \(2PbSO_4+O_2 ightarrow 2PbO + 2SO_2\) - (ii) Impurities may poison the catalyst and moisture can cause corrosion and unwanted side - reactions. - (iii) \(2SO_2+O_2 ightleft…
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the diagram below shows a set up to show the catalytic oxidation of amm…
(a) A. Manganese(IV) oxide (\(MnO_2\)) B. Hydrogen peroxide (\(H_2O_2\)) (b) Brown fumes are formed. (c) \(2H_2O_2(aq)\xrightarrow{MnO_2}2H_2O(l)+O_2(g)\)
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2. the following elements belong to the same group of the periodic tabl…
(a) Metals. Low first ionization energies and atomic radius > ionic radius (for cation formation). (b) Element C.
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2. a change in ______ means that a chemical reaction has occurred. (1 p…
the properties and identity of the reacting substances
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read the passage from sugar changed the world. we all crave sweetness, …
Sugar cane is no longer the main source of sweetness for most people.
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what is common between transverse waves and longitudinal waves? both in…
Both move faster at higher temperatures.
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na (aq) + oh (aq) + h (aq) + cl (aq) → na (aq) + cl (aq) + h₂o(l) part …
- Part 3 of 4: Yes - Part 4 of 4: \( \text{OH}^-(aq)+\text{H}^+(aq)\to\text{H}_2\text{O}(l) \)
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11. define electronegativity. what is the trend when moving across the …
Electronegativity: ability of an atom in a compound to attract electrons. Across - period trend: increases. Down - group trend: decreases. Cause across - period: increased nuclear…
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10. analyze the graph above. what patterns or trends do you see? why is…
The general trend is that ionization energy increases across a period and decreases down a group. The decrease between Ne and Na (or Ar and K) is because Ne (Ar) has a stable full…
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na (aq) + oh (aq) + h (aq) + cl (aq) → na (aq) + cl (aq) + h₂o(l) part …
Yes For the net - ionic equation:
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answer the following questions and be sure to include all physical stat…
Na⁺(aq) + OH⁻(aq) + H⁺(aq) + Cl⁻(aq) → Na⁺(aq) + Cl⁻(aq) + H₂O(l)
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7. graph atomic radius vs. atomic number for the period 3 elements. wha…
The trend is that as atomic number increases, atomic radius decreases. This is because with more protons (higher atomic number) in the same - shell period (Period 3), the nuclear …
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select the single best answer. the passage of electricity through an el…
both cations and anions
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identify the following substance as a strong electrolyte, weak electrol…
strong electrolyte
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what is the formula for ammonium sulfate? a (nh4)2so4 b nh3so4 c nh42so…
A. (NH4)2SO4
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any combination of non - metals a ionic b covalent
B. Covalent
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any combination of non - meta o a lonic o b covalent question 38 (2 poi…
a. magnesium sulfate
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oxygen has ___ valence electrons, therefore it always forms ___ bonds. …
d. 6 valence electrons, 2 bonds
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oxygen has ____ valence electrons, therefore it always forms ____ bonds…
- Question 34: d. beryllium chloride - Question 35: a. \(NaNO_{3}\)
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name the following ionic compound: cs2s o a cesium ii sulfate o b cesiu…
For \(Cs_2S\): C. cesium sulfide For \(NaCl\): A. Ionic
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question 29 (2 points) mgo (magnesium oxide) a ionic b covalent
A. Ionic
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name the following ionic compound: lino₃ a lithium nitride b lithium ox…
d. lithium nitrate
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4. hcl is a corrosive colourless gas that dissolves readily in water. a…
\(-74.2\space kJ/mol\)
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if a corn producer uses 5 - 15 - 5, which nutrient is most abundant in …
- First question: a. Phosphorous - Second question: d. iron(III) chloride
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brushed off of one piece of matter and onto another. as electrons are b…
- From the Findings section: Charge separation in clouds (negative at bottom, positive at top), electron count in lightning (\(1\times10^{20}\)), time of electron movement (\(\sim…
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what is the process called when a solid changes directly into a gas?
Sublimation
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which of the following is an example of a physical change? metal rustin…
honey dissolving in tea
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separating mixtures based on boiling points. density decantation distil…
Distillation
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the tendency of a substance to undergo chemical changes is________.mall…
Reactivity
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which branch of chemistry is based on materials containing carbon analy…
Organic
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a physical property that does not depend on the amount of substance pre…
Intensive property
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when, in disgrace with fortune and mens eyes, i all alone beweep my out…
abab
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how is a poems rhyme scheme marked and identified? punctuation symbols,…
upper or lowercase letters, such as "ABAB"
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formation of ice is a __________ chemical change physical change
physical change
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which one of these is a chemical property? flammability color boiling p…
flammability
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which website citations are formatted correctly? choose three correct a…
Lawson, Jennifer. Put Down the Pesticides. Organic Advocates, 31 May 2013. Web. 3 January 2014; Greene, Tom. Home Composting. Hanover Growers Guild, 15 March 2010. Web. 22 April 2…
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1. identify each of the following being qualitative (1) or quantitative…
1. Sodium will react with water - B. Chemical Property 2. The Boiling point of water is \(212^{\circ}F\) - A. Physical Property 3. The acid turned the penny green - D. Chemical Ch…
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fill in the blanks to complete each statement about weathering. weather…
sediment, Physical (mechanical), Chemical
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consider the following system at equilibrium where $delta h^{circ}=-87.…
- The value of \(K_c\): remains the same - The value of \(Q_c\): is less than \(K_c\) - The reaction must: run in the forward direction to reestablish equilibrium - The number of …
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summer magic by leslie pinckney hill so many cares to vex the day, so m…
B. Summer's warmth brings renewed life.
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use the references to access important values if needed for this questi…
- The value of \(K_c\): remains the same - The value of \(Q_c\): is equal to \(K_c\) - The reaction must: remain the same. It is already at equilibrium. - The number of moles of \…
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use the references to access important values if needed for this questi…
- The value of \(K_{c}\): remains the same - The value of \(Q_{c}\): is greater than \(K_{c}\) - The reaction must: run in the reverse direction to reestablish equilibrium - The c…
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3. examine the reaction mechanism found below: a + b₂ → ab₂ (slow) ab₂ …
a. Reaction intermediates: \(AB_2\), \(AB_2C\), \(B_2C_2\) (circle these) b. Catalyst: \(A\) (box this) c. Overall equation: \(2C + B_2 ightarrow D + E\) d. Rate law: \(Rate = k[A…
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select the correct answer from the drop - down menu. which transitional…
However
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21. based on the electron configuration of the bohr model shown, what e…
Carbon
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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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multiple choice 10 points why does ice float on water? ice and water ha…
- For "Why is water considered a polar molecule?": It has a positive charge on the Hydrogen (H) side and a negative charge on the Oxygen (O) side. - For "Why does ice float on wat…
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read the excerpt from \sonnet 29.\ when, in disgrace with fortune and m…
abab
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7 multiple choice 10 points what is the chemical description of water? …
\(H_2O\)
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5 multiple choice 10 points why is water considered a \universal solven…
It dissolves more substances than any other liquid.
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freeze at 32°f, boil at 212°f freeze at 212°f, boil at 0°f multiple cho…
3. What is capillary action? - The ability of water to move upward through small openings. 4. How do cohesion and adhesion help capillary action? - Cohesion makes water molecules …
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use the link below to access the reading and then answer the fol readin…
It makes water tend to clump together in drops.
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2) na₂co₃(aq) + cacl₂(aq) → 2 nacl(aq) + caco₃(s) calculate the volume …
\(100\space mL\)
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1) in this experiment, you will be mixing aqueous solutions of sodium c…
Step 1: Compute the mass of calcium carbonate to moles of calcium carbonate Step 2: Compare moles of calcium carbonate to moles of sodium carbonate based on balanced equation to c…
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part b read each scenario. decide whether a physical or chemical change…
1. Physical change; Only form (cutting, spreading) is changed. 2. Chemical change; Burning (new substances like carbon, smoke are formed). 3. Chemical change; Rust (new substance)…
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which of the following may result in cancer? i. radiation exposure ii. …
I, II, III, & IV
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nomenclature worksheet 5: ionic compounds summary name the following co…
1. Calcium fluoride 2. Sodium oxide 3. Barium sulfide 4. Copper (II) sulfate 5. Iron (III) oxide 6. Mercury (II) chloride 7. Silver nitrate 8. Magnesium carbonate 9. Potassium ace…
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reactants appearance of reactants observations after mixing (select all…
For \(Zn(s)+H_2SO_4(aq)\): Observations - Bubbles formed in mixture; Products - \(H_2(g)\), \(ZnSO_4(aq)\) For \(Mg(s)+HCl(aq)\): Observations - Bubbles formed in mixture, Test tu…
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please complete the following table: 1. carbon dioxide 2. phosphorus tr…
| Name of Covalent Compound | Formula of Covalent Compound | | --- | --- | | 1. carbon dioxide | \(CO_{2}\) | | 2. phosphorus triiodide | \(PI_{3}\) | | 3. sulfur dichloride | \(S…
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10. how does the structure of the molecule relate to how quickly the ha…
The structure of the molecule determines the strength of its intermolecular forces which influences the rate of evaporation.
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9. the students want to test an additional substance in their experimen…
A. A substance with a lower boiling point than methanol because it will have weaker intermolecular forces.
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8. drag and drop the words/phrases to explain the patterns that cause h…
As thermal energy transfers from a person's hand into the hand sanitizer, the forces of electric attraction between the molecules of sanitizer can no longer keep the molecules clo…
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use the references to access important values if needed for this questi…
The reaction quotient \(Q_c\) equals \(4.65\times 10^{-5}\). The reaction must run in the forward direction to reach equilibrium.
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consider the following reaction where ( k_{c}=154 ) at ( 298 mathrm{~k}…
The reaction quotient, \(Q_{c}\), equals \(82.5\). The reaction \(A. must run in the forward direction to reach equilibrium\)
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7. suppose you want to use one of the substances in figure 1 as hand sa…
The addition of water would increase the intermolecular forces and decrease the evaporation rate.
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6. how does the difference in evaporation rates in figure 2 serve as ev…
A slower evaporation rate is evidence of stronger intermolecular forces.
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3. how can boiling point be used to predict the strength of intermolecu…
The stronger the forces between molecules, the higher the boiling point
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5. how do patterns at the molecular scale explain the results in figure…
1. electric attraction 2. stronger 3. slower
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4. refer to figure 1. what causes a difference in boiling point between…
The strength of the attractive forces between the molecules.
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use the references to access important values if needed for this questi…
\(Q_c = 0.0146\). The reaction must run in the reverse direction to reach equilibrium.
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2. if 0.250 g of fuel increases the temperature of a calorimeter by 20 …
\(582.4\space kJ/g\)
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displacement reactions involving metals reactants appearance of reactan…
Observations: Bubbles formed in mixture Products: \(H_2(g)\), \(ZnSO_4(aq)\)
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the equilibrium constant, ( k_{c} ), for the following reaction is ( 5.…
REACTANT LOW
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heather is doing an acid - base reaction. she has 25.00 ml of hydrochlo…
a buret
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sian wants to measure the number of seconds that it takes for the conte…
a stopwatch
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which of the following elements would form a cation?* oxygen flourine m…
First question: Magnesium. Second question: electrons are shared between two nonmetals.
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will co₂ mix with ch₄?* yes no maybe why?
A. yes
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what force is the strongest in the h₂0 molecule? * 1 point dipole - dip…
Hydrogen bonding
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3a. which is more reactive with iron ions? water chloride 3b. which is …
3a. Chloride 3b. Thiocyanate 3c. Hydroxide 3d. Hydroxide
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which set of elements would make a polar covalent bond? (electronegativ…
O and I
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circle the correct answer. 57. which ion gained electrons(s) mg²+ or cl…
57. \(Cl^{1-}\) 58. \(Ca^{2+}\) 59. False 60. True
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which process is a sign of a chemical change? a melting block of ice le…
A rotting potato gives off a bad smell.
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seans bike begins to rust in the winter. what tells sean that a chemica…
The metal is beginning to rust.
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which process is an example of a physical change? sodium metal and chlo…
Cutting carrots into pieces and mixed in a salad.
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select the most appropriate tool for each measurement. exactly 200.00 m…
graduated cylinder
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circle the correct answer. 57. which ion gained electrons(s) mg²+ or cl…
63. \(|O - S|=|3.4 - 2.5| = 0.9\) 64. Polar Covalent 65. \(|Cl - C|=|3.2 - 2.5|=0.7\) 66. Polar Covalent 67. \(|Br - K|=|3.0 - 0.8| = 2.2\) 68. Ionic 69. \(|Br - Br|=|3.0 - 3.0| =…
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select the most appropriate tool for each measurement. exactly 200.00 m…
Exactly 200.00 mL salt solution: volumetric flask A 0.02 - mL acid solution: 1 - mL pipette Approximately 400 mL water: beaker
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which process is an example of a physical change? ice melting milk sour…
Ice melting
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17. considering the water molecule which on the surface seems to be geo…
- **Question 17**: The oxygen atom in \(H_2O\) has two lone pairs. Lone - pair repulsion causes a bent shape. Oxygen is more electronegative than hydrogen. Bond dipoles in the non…
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select the most appropriate tool for each measurement. exactly 200.00 m…
Exactly 200.00 mL salt solution: volumetric flask Approximately 400 mL water: beaker Exactly 77.5 mL methanol: graduated cylinder
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which process is an example of a physical change? cutting carrots into …
Cutting carrots into pieces and mixed in a salad.
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how does ninhydrin work to develop latent fingerprints? the dye in it r…
Ninhydrin reacts with amino acids in the perspiration of the fingerprint.
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the equilibrium constant, ( k_{c} ), for the following reaction is ( 7.…
\(0.214\)
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reactions involving acids reactants appearance of reactants observation…
- For \(Na_{2}CO_{3}(aq)+HCl(aq)\): Observations - Bubbles formed in mixture; Products - \(CO_{2}(g)\), \(H_{2}O(l)\), \(NaCl(aq)\) - For \(NaOH(aq)+HCl(aq)\): Observations - Test…
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(sc8.p9.2) mrs. flores asked her class to describe a chemical change. w…
A chemical change produces new substances with different properties than the original substances.
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most appropriate for him to use? grams complete kwame wants to measure …
degrees Fahrenheit to degrees Celsius
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13. which of the listed molecules is not geometrically linear? a. carbo…
13. b. Water (\(H_2O\)) 14. The negative end of the dipole (points to the more electronegative atom/region of higher electron density) 15. a. Polar due to its uneven distribution …
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match the word with its meaning. write the letter in the space provided…
1. C 2. H 3. E 4. G 5. I 6. D 7. F 8. J 9. K 10. A 11. B 12. valence 13. lone pair
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sarah is completing a lab in which she is required to identify an unkno…
density
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ice cubes water droplets liquid at happens when you add energy to a liq…
Evaporation