Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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a solution contains 90 ml of methanol, 18 ml of propanol, and 2 ml of d…
A. methanol
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which of these is an example of a physical change? o sugar, when heated…
solid ice, when heated, turning into liquid water
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which statement describes a chemical property of water? it reacts with …
It reacts with sodium metal.
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which is an example of a nonaqueous solution? gasoline fog mayonnaise f…
A. gasoline
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hypothesis: if the temperature of the liquid is increased, then more su…
format: "If... then... because...", independent variable: temperature, dependent variable: solubility, reason: higher temperatures increase solubility (or lower temperatures decre…
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answer the lab question (\what is the effect of temperature on the solu…
As the temperature of the liquid increases, the solubility of the solid in the liquid will increase.
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lesson question: what is the effect of temperature on the solubility of…
format: “What is the effect of X on Y?”, materials: solid dissolved in a liquid, independent variable: temperature, dependent variable: solubility
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by the end of this lab, you will determine whether you should add cocoa…
Does the solubility of cocoa mix in water increase or decrease with an increase in water temperature?
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question 3(multiple choice worth 4 points) (04.05 mc) what type of ener…
C. Chemical energy to electrical energy
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18) draw orbital diagrams for the following elements: oxygen: how many …
Oxygen: Orbital diagram: 1s(↑↓) 2s(↑↓) 2p(↑↓ ↑ ↑), 2 unpaired electrons. Magnesium: Orbital diagram: 1s(↑↓) 2s(↑↓) 2p(↑↓ ↑↓ ↑↓) 3s(↑↓), 0 unpaired electrons.
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5. categorize the energies into potential and kinetic energies. electri…
Potential Energies: Gravitational, Elastic, Chemical, Nuclear Kinetic Energies: Mechanical, Thermal, Sound, Radiant, Electrical
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4. in this multiple energy conversion example, is all the energy of the…
No, because some of the energy is transferred as heat and sound from friction in the bike, gears, and generator.
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4. test your understanding of isotopes by examining the relationships b…
第一组：Isotopes 第二组：Same Atom, Not Isotopes of Each Other 第三组：Isotopes 第四组：Isotopes 第五组：Same Atom, Not Isotopes of Each Other
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find the mass of 29.0 l of hydrogen gas (at stp).
$2.59\ g$
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multiple - choice question cohesion between water molecules contributes…
B. Surface Tension
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multiple - choice question what is adhesion? the ability of water to di…
Water molecules sticking to surfaces.
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multiple - choice question what is cohesion? water molecules sticking t…
C. Water molecules sticking to other water molecules.
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multiple - choice question in this animation, what is the nacl? (sodium…
B. solute
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which of the following conversions is correct and expresses the answer …
The first conversion $3.779\ \text{lb}\times\frac{454\ \text{g}}{1\ \text{lb}}\times\frac{1000\ \text{mg}}{1\ \text{g}} = 1.7\times 10^{6}\ \text{mg}$ and the second conversion $5…
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melanoma rates are higher in areas of the united states with a high num…
C. People who use sunscreen have lower rates of skin cancer in general.
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7. bleach is an example of which group of chemicals used for disinfecti…
7. B. halogens 8. C. in - use test 9. A. phenol 10. Hand - washing
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chapter 2 important terms define these terms from chapter 2 of your tex…
1. A substance that donates hydrogen ions (H⁺) in solution. 2. A molecule that stores and transfers energy in cells. 3. A substance that accepts hydrogen ions (H⁺) or donates hydr…
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3 ste nomme les composés suivants. a) sibr4: b) v2o5: c) agcl: d) pbl2:…
# Explications étape par étape: ## Étape 1: Nommer les composés de la question 3 ### a) SiBr₄ Le silicium est un élément et le brome est un autre élément. On a 4 atomes de brome p…
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what is the activation energy? the energy needed to start doing your wo…
The energy needed to start a reaction
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prepwork part 1: for each of the atoms/ions below, write the full elect…
1. Neutral atom of cobalt: 1s²2s²2p⁶3s²3p⁶4s²3d⁷ 2. Chlorine ion with a charge of - 1: 1s²2s²2p⁶3s²3p⁶ 3. Neutral atom of iodine: [Kr]5s²4d¹⁰5p⁵ 4. Neutral atom of vanadium: [Ar]4…
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4. how does lightning fixation occur? a. lightning causes nitrogen gas …
4. a. Lightning causes nitrogen gas molecules to break apart and react with oxygen. 5. b. the conversion of nitrate into atmospheric nitrogen 6. b. combustion of fossil fuels and …
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the chemical formula for an emerald is be₃al₂(sio₃)₆. an emerald can be…
a pure substance because it is a compound.
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which is a substance that is made up of only one type of atom? compound…
B. element
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a solid precipitate is formed from the reaction of lead nitrate and sod…
C. filtration
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which best describes an element? a pure substance a type of a mixture a…
a pure substance
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which best describes a compound such as sodium chloride? a pure substan…
a pure substance that can be separated into different elements by chemical means
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which is a characteristic of mixtures? they are chemically bonded toget…
They can be separated by physical processes.
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a teacher makes the following statement. \gasoline boils at a relativel…
distillation of a mixture
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the table shows the percentages of hydrocarbons that are found in a sam…
a mixture
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which cannot be chemically broken down into simpler substances? compoun…
B. element
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9 what is the step 3 of how to calculate average atomic mass? (1 point)…
Add up all the masses. Round to two decimal places and label your answer as "amu".
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there are four isotopes of sulfur: 1) sulfur-32 95.0% abundance 2) sulf…
$32.09$ amu
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7 a unit of mass used to show atomic mass, equal to one - twelfth of th…
atomic mass unit (amu)
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christian conducts an experiment to test the hypothesis that adding sug…
make sure the results are reliable
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6 what is the step 2 of how to calculate average atomic mass? (1 point)…
Multiply each decimal by its mass number.
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part iii: calculate the average atomic mass for the following isotopes.…
1) The average atomic mass of neon is $20.18$. 2) The average atomic mass of element X is $56.8$.
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what is step 1 of how to calculate average atomic mass? (1 point) multi…
Move the decimal two places to the left in each percent abundance.
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all copper in the world exists as two isotopes: 1) copper - 63, which h…
63.62 amu
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two recent models of the atom are shown below. the modem model has repl…
Evidence from new investigations led to the development of the modern model.
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part ii: fill in the chart with the missing information about the given…
| Name Notation | Notation | Mass Number | Atomic # | Protons | Neutrons | Electrons | |---|---|---|---|---|---|---| | Boron - 14 | $_{5}^{14}B$ | 14 | 5 | 5 | 9 | 5 | | Cesium - …
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1. the weighted average of the atomic masses of the naturally occurring…
C. average atomic mass
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solve the question below. (1 point) naturally occurring europium (eu) c…
Eu - 151: 51.5%, Eu - 153: 48.5%
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1. the ______________ depends on the mass number and the percent abunda…
C. average atomic mass
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investigation procedures investigation statement 1 to make a mixture, s…
C. 3
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jacob conducted an investigation to determine the effect of acid on dif…
It might lead to the development of new investigations.
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7. how many grams of lithium sulfate are needed to make 250.0 ml of a 2…
$64.6\ g$
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6. how much of a 0.33 m h2so4 solution is needed to make 500.0 ml 0.075…
$113.6\ mL$
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5. what is the molarity of 18 g of hcl dissolved in enough water to mak…
$0.659\ M$
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the poem \mending wall\ differs from many of frosts poems because... it…
it does not have a consistent rhyme scheme.
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7. balance the following chemical reactions. a) 2c + o₂→ co b) cl₂ + na…
a) $2C + O_2 ightarrow 2CO$ b) $Cl_2 + 2NaBr ightarrow Br_2+2NaCl$ c) $2NH_3 ightarrow N_2 + 3H_2$ d) $2Na + 2H_2O ightarrow 2NaOH + H_2$ e) $2NaOH + H_2S ightarrow Na_2S + 2H_2O$
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5. write a chemical equation from each of the following word equations.…
a) $2H_2O ightarrow 2H_2 + O_2$ b) $2Li + 2H_2O ightarrow 2LiOH + H_2$ c) $Zn + 2HCl ightarrow ZnCl_2+H_2$ d) $KI+AgNO_3 ightarrow KNO_3 + AgI$
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extension: get the gizmo ready: select lithium (li) from the select a m…
1 - A. 1 1 - B. Sodium (Na) 1 - C. 1 2 - Beryllium: 2, Magnesium: 2, Nitrogen: 5, Phosphorus: 5, Oxygen: 6, Sulfur: 6, Fluorine: 7, Chlorine: 7 3. Elements in the same chemical fa…
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the maillard reaction is a chemical process that occurs when foods like…
The Maillard reaction is a chemical reaction that occurs between acids and sugars, causing foods to brown and gain a rich flavor. This process enhances the smell and taste of cert…
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question 4 of 5 which of the following is the correct definition of vit…
D. Nutrients that help the body use proteins, carbohydrates, and fats.
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activity b: ionic compounds get the gizmo ready: click reset. turn off …
1. A. 1 B. 2 C. Yes, because two lithium atoms can each give 1 electron to an oxygen atom, making the lithium atoms stable with 2 electrons in their outer - shell and the oxygen a…
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multiple choice 1 point what was antoine lavoisiers contribution to the…
1. He came up with a widely - read, precise description. 2. Oxygen interacts with iron to form rust.
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activity a: ions get the gizmo ready: • click reset. • check that sodiu…
1. A. Sodium: 11, Chlorine: 17 B. Sodium: 11, Chlorine: 17 2. Sodium: 1, Chlorine: 7 3. A. Sodium: \(+1\), Chlorine: \(-1\) B. Both ions are stable. Sodium ion has a full outer - …
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what was antoine lavoisiers contribution to the law of conservation of …
1. He was the first person to propose it in a scientific way. 2. Oxygen interacts with iron to form rust.
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4 grams of hydrogen and 32 grams of oxygen will combine to form: 36 gra…
A. 36 grams of water B. 6 grams
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fill in the name and empirical formula of each ionic compound that coul…
| cation | anion | empirical formula | name of compound | | ---- | ---- | ---- | ---- | | $Fe^{3+}$ | $BrO_{3}^{-}$ | $Fe(BrO_{3})_{3}$ | iron(III) bromate | | $Co^{3+}$ | $ClO_{3…
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for each row in the table below, decide whether the pair of elements wi…
| element #1 | element #2 | compound formed? | chemical formula | | ---- | ---- | ---- | ---- | | barium | beryllium | neither | | | barium | oxygen | ionic | $BaO$ | | calcium | …
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fill in the systematic names of the following chemical compounds. note:…
| molecular formula | name of compound | | ---- | ---- | | $C_3S_2$ | tricarbon disulfide | | $BP$ | boron phosphide | | $CS_2$ | carbon disulfide | | $BI_3$ | boron triiodide | |…
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complete the table below. some binary molecular compounds name chemical…
| name | chemical formula | |--|--| | phosphorus pentachloride | $PCl_{5}$ | | tetraphosphorus heptasulfide | $P_{4}S_{7}$ | | phosphorus trichloride | $PCl_{3}$ | | tetraphosphor…
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balance the chemical equation below using the smallest possible whole n…
$P_4(s)+3NaOH(aq)+3H_2O(l) ightarrow 3PH_3(g)+3Na_2HPO_3(aq)$
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down 1. most active nonmetals 2. group ii metals 3. the atomic number i…
1. Halogens 2. Alkaline earth metals 3. Protons 7. Positive 9. Number 11. Groups
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down 1. most active nonmetals 2. group ii metals 3. the atomic number i…
1. Halogens 2. Alkaline earth metals 3. Protons 7. Positive (cation) 9. Number 11. Groups
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6. what is similar about the valence shell in the halogens family?
All elements in the halogen family have 7 valence electrons.
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question 6 if q = k the reaction is at equilibrium the reaction will go…
1. The reaction is at equilibrium 2. K is based on concentrations at equilibrium, while Q is based on concentrations at any point in the reaction
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how can we figure out if a reaction is going to go forward or backward?…
For the first question: B. compare the values of Q and K For the second question: B. The reaction proceeds to the right, forming more products.
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question 1 a reaction quotient, $q_c$, can be expressed using ...... co…
1. B. ...any... 2. B. Partial pressures. 3. C. The value of Qc is variable.
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9. what distinguishes clastic sedimentary rocks from chemical sedimenta…
Clastic rocks are composed of fragments of other rocks, while chemical rocks form from mineral precipitation
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5. what is similar about the valence shell in the alkaline earth metals…
All elements in the Alkaline Earth Metals Family have 2 valence electrons in their valence shell.
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what is similar about the outer shell of electrons (valence shell) in t…
Each atom in the Alkali Metals Family has 1 electron in its valence shell.
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8. a substance is poured from one container to another, but the shape d…
8. c. Solid 9. a. Faster 10. c. Gas 11. c. The chemical composition. 12. c. There is not enough information to answer this question 13. a. Gas 14. d. Both a and c 15. c. The volum…
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6. what type of motion do particles in a liquid have? slip and slide an…
5. Particles in a liquid can slip and slide and twist past one another, vibrate slowly and float freely to fill a container. 7. Particles in a gas can slip and slide and twist pas…
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2. the particle theory of matter states that— all phases of matter have…
2. All phases of matter have atoms that are constantly moving. 3. The amount of mass in a given volume. 4. A substance that has mass and volume. 5. Slip and slide and twist past o…
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2. the particle theory of matter states that— all phases of matter have…
All phases of matter have atoms that are constantly moving.
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the frame rou state of matter shape: volume: particle motion: example:
Shape: Not definite Volume: Not definite Particle Motion: Fast and random Example: Oxygen
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6. in the modern periodic table, elements are arranged according to a. …
There is no option indicating increasing atomic number among the given choices. But if we were to correct the options and choose the correct one, it should be "increasing atomic n…
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what is $delta_{r}h^{circ}$ for the following chemical reaction? $h_{2}…
$21.9\ kJ/mol$
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construct the expression for kc for the following reaction. co(g) + 2 h…
$K_c=\frac{[CH_3OH]}{[CO][H_2]^2}$
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at high temperature, so₂ and no₂ react according to the equation below.…
\(K_c=\frac{[SO_3][NO]}{[SO_2][NO_2]}\)
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read the paragraph, and then complete the model. fossil fuels are subst…
Atmosphere, Biosphere
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at high temperature, so₂ and no₂ react according to the equation below.…
\[K_c=\frac{[SO_3][NO]}{[SO_2][NO_2]}\]
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read the paragraph, and then complete the model. fossil fuels are subst…
Geosphere, Atmosphere
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questions 6 - 13: circle the choice that best answers each question. 6.…
6. b. Stays the same, stays the same 7. b. Reversible 8. b. Strength of intermolecular forces, c. Speed of particles 9. a. There can be a change in heat (kJ) without the temperatu…
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at high temperature, so₂ and no₂ react according to the equation below.…
| Species | Initial (M) | Change (M) | Equilibrium (M) | | ---- | ---- | ---- | ---- | | $SO_2$ | $2.00$ | $- 1.30$ | $0.70$ | | $NO_2$ | $2.00$ | $- 1.30$ | $0.70$ | | $SO_3$ | $…
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challenge me questions 1-5: as you explore the simulation, answer the f…
1. No. 2. The more energy molecules have, the more they move. 3. Because water evaporates into gas and escapes. 4. Gas to Liquid: condensation; Liquid to Gas: evaporation; Liquid …
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ck - 12 exploration series phase change heat and changes of state explo…
1. No 2. More energy leads to more vigorous molecular motion. 3. Because water changes to water vapor and escapes. 4. Gas to Liquid: condensation; Liquid to Gas: evaporation; Liqu…
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what is the ultimate goal of measuring the vapor pressure of ethanol at…
To calculate the heat of vaporization ($\Delta H_{vap}$) of ethanol.
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question 4 of 10 > points earned: 0.00/1.00 why is it necessary to use …
Because the pressure of a fixed amount of gas in a sealed container increases as its temperature increases.
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question 10 of 10 points possible: 1.00 why is it important to twist th…
To prevent any of the gas (air or ethanol vapor) from leaking out, which would cause inaccurate pressure readings.
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question 9 of 10 > points possible: 1.00 what is the primary safety haz…
It is flammable and poisonous.
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question 8 of 10 > points possible: 1.00 based on the principles discus…
The vapor pressure increases.
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question 7 of 10 > points possible: 1.00 not yet answered the slope of …
39,900 J/mol