Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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sublimation is when a solid gains energy and becomes a gas, skipping th…
It skips changing into a liquid and becomes a gas.
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note: to answer some of the questions, it may help to reference a perio…
There are more than eight valence electrons around the central atom of iodine, expanding its valence shell.
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there are different types of atoms everything is made up of the atoms o…
Selenium atoms
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its time for the unit exam. this is your opportunity to show how much y…
the sea of electrons being freely shared between the positive nuclei of the metal atoms
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gaseous butane (ch₃(ch₂)₂ch₃) reacts with gaseous oxygen gas (o₂) to pr…
\(53\%\)
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use the following balanced equation to answer the questions: 3rb + p → …
\(256.41\space g\)
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the different colored squares on the periodic table show elements that …
Mercury (Hg)
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read the passage from a letter that president jimmy carter wrote to con…
Protecting the environment is essential for maintaining Americans’ quality of life.
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a certain atom has 20 electrons, 20 neutrons, and 20 protons. what is t…
B. 40
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graph the heating curve of water with the following conditions: 1. a 30…
- **Graph Title**: Heating Curve of a 30 - gram Water Sample - **X - axis Title**: Time (minutes) - **Y - axis Title**: Temperature (°C) - **Labels**: - 0 - 2 minutes: Ice (solid)…
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chemical reactions and chemical equations rewrite the following sentenc…
1. Word equation: Iron + oxygen → iron(III) oxide; Balanced equation: \(4Fe + 3O_2 ightarrow2Fe_2O_3\) 2. Word equation: Hydrogen chloride + sodium carbonate → carbon dioxide + so…
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balancing equations starting with the skeleton equations, balance the f…
1. \(H_2+F_2 = 2HF\) 2. \(2Sn + O_2=2SnO\) 3. \(MgCl_2=Mg + Cl_2\) 4. \(2KNO_3=2KNO_2 + O_2\) 5. \(2BN + 3F_2=2BF_3+N_2\) 6. \(CuI_2+Fe = FeI_2+Cu\) 7. \(2Li+2H_2O = 2LiOH + H_2\)…
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\matter cannot be created or destroyed\ during a chemical or physical c…
Matter (or Mass)
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the weight of sodium chloride after dissolution in water will decrease …
B. FALSE
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comprehension check! 1. what are the three subatomic particles that mak…
1. Protons (positive), neutrons (neutral) in nucleus; electrons (negative) in electron - shells. 2. Electron mass $\ll$ proton/neutron mass. 3. Number of neutrons = mass number - …
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what does wood combine with when it is burned? a water b it doesnt comb…
d. oxygen
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in addition to ash, what is produced when wood burns? a carbon dioxide …
A. carbon dioxide and water vapor
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which of the following statements support the law of mass conservation …
C. Atoms can be rearranged
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the law of conservation of mass states that matter cannot be created or
destroyed
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according to conservation of mass, what is the mass of ice made from a …
C. equal to that of the water
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section 10.1 measuring matter in your textbook, read about counting par…
1. pair 2. \(5\) 3. dozen 4. gross 5. \(200\) 6. ream 7. \(6,000,000,000\) 8. \(0.5\space mol\) 9. \(6.02\times 10^{23}\) 10. four moles
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est your knowledge question 3 combination decomposition 2nacl→2na+cl₂ d…
\(2NaCl ightarrow2Na + Cl_{2}\): Decomposition; \(2Na+Cl_{2} ightarrow2NaCl\): Combination; \(Li + NaCl ightarrow LiCl+Na\): Single displacement; \(AgNO_{3}+NaCl ightarrow AgCl + …
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c₃h₈(g) + o₂(g) co₂(g) + h₂o(l) zn(s) + hcl(aq) zncl₂(aq) + h₂(g) naoh(…
1. \(1,5,3,4\) 2. \(1,2,1,1\) 3. \(2,1,1,2\) 4. \(1,1,1,2\)
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categorize each change as physical change or chemical change. a butane …
- **Physical Change**: Rubbing alcohol evaporates, Sugar dissolves in water, Water boils. - **Chemical Change**: A butane lighter produces a flame, A screwdriver left outside in t…
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passage #3 - gail denvers denvers experienced the highlight of any spri…
- Passage #3: d. Description - Passage #4: c. Problem/Solution - Passage #5: a. Cause and Effect
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25. calculate the volume in milliliters of a 1.420 m naoh solution requ…
D. \(158.5\space mL\)
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24. aspirin, ( c_{9}h_{8}o_{4} ), is produced by the reaction of salicy…
D. 51.6%
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directions: match the text structure to its definition. a. cause and ef…
Passage #1: B. Compare and Contrast Passage #2: E. Sequential
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use what you have learned about atoms and coulombs law to complete the …
- First blank: inner - Second blank: outer - Third blank: nuclear - Fourth blank: effective nuclear - Fifth blank: increases - Sixth blank: decreases - Seventh blank: higher
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23. ammonia reacts with diatomic oxygen to form nitric oxide and water …
C. 33.8 g
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multiple choice questions answer the following multiple choice question…
1. D. It is rearranged. 2. C. Antoine Lavoisier 3. C. A piece of paper is burned. 4. D. The atoms are rearranged. 5. D. It helps scientists understand how matter works. 6. A. It p…
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22. phosphoric acid can be prepared by reaction of sulfuric acid, h₂so₄…
B. \(H_2SO_4\)
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21. how many moles of oxygen are formed when 58.6 g of kno3 decomposes …
D. \(0.724\space mol\)
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20. how many moles of nh₃ are required to produce 10.0 mol of h₂o? 4nh₃…
C. \(6.67\space mol\)
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2. why do elements in the same group have similar chemical characterist…
Elements in the same group have similar chemical characteristics because they have the same number of valence electrons.
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which two parts of the activity indicate a chemical reaction occurs whe…
B. The temperature of the water increases; E. The separated substance has a different density than calcium oxide.
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1. what do periods (rows) on the periodic table correspond to? a. a spe…
C. energy levels of electrons
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3. if a neutral atom has three electrons, how many protons does it have…
3 ### Question 4
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methane burning reaction
6. \(1\) 7. \(1\) 8. \(4\) 9. \(4\) 10. \(4\) 11. \(4\)
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question #4 a teacher drew three figures on the board. which option cor…
A. Figure 1: element; Figure 2: compound; Figure 3: mixture
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based on the following balanced equation: 2h₂ + o₂ → 2h₂o how many mole…
\(8\)
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based on the following balanced equation: 3li + alcl₃ → 3licl + al how …
\(3\)
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based on the following balanced equation: 2h₂s + 3o₂ → 2so₂ + 2h₂o how …
\(6\)
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6 points possibles classez les substances suivantes selon quelles sont …
| Sels | Bases | Acides | |------|-------|--------| | LiBr | CsOH, B(OH)₃, CaO | H₂Se, HClO₃ |
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based on the following balanced equation: 2c₂h₂ + 5o₂ → 4co₂ + 2h₂o wha…
\(5O_2:2H_2O\)
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8. if 25.0 ml of 1.50 m hydrochloric acid is diluted to a volume of 500…
A. \(0.0750\space M\)
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based on the following balanced equation: 2ag₂o → 4ag + o₂ what is the …
\(2Ag_2O:4Ag\) (the option \(2Ag_2O:4Ag\) in the given choices)
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ased on the following balanced equation: 2ai + 3cl₂ → 2aici₃ what is th…
\(2\text{Al}:2\text{AlCl}_3\)
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use the following balanced equation to answer the questions: 2koh→k₂o +…
\(18.02\space g\)
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use the following balanced equation to answer the questions: 2koh→k₂o +…
1
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use the following balanced equation to answer the questions: 3rb + p → …
\(3\) moles
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use the following balanced equation to answer the questions: 3rb + p → …
\(3\)
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use the following balanced equation to answer the questions: 2h₂ + o₂ →…
\(4.04\ g\)
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use the following balanced equation to answer the questions: 2h₂ + o₂ →…
\(2\) moles
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use the following balanced equation to answer the questions: 2h₂ + o₂ →…
\(2\)
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for the following compounds, give the cation and anion with their charg…
| Compound | Cation | Anion | Compound Name | |---|---|---|---| | \(Na_2HPO_4\) | \(Na^+\) | \(HPO_4^{2 - }\) | Disodium hydrogen phosphate | | \(MgCl_2\) | \(Mg^{2+}\) | \(Cl^-\)…
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determine the number of particles in the 2.50 mol sample of nacl. 1 mol…
The coefficient is \(1.51\) (rounded to two decimal places) and the exponent is \(24\).
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given 146 g of nacl, determine the number of moles of nacl. 1 mol nacl …
\(2.50\)
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what is the molar mass of nacl? 1 mol na = 22.99 g na 1 mol cl = 35.45 …
58.44
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qui suis - je? choisissez la bonne réponse dans le menu déroulant. a) m…
a) Acide b) Acide c) Sel
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determine the number of particles in the 4.50 mol sample of ch₂cl₂. 1 m…
Coefficient: \(2.71\), Exponent: \(24\)
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given 382 g of ch₂cl₂, determine the number of moles of ch₂cl₂. 1 mol c…
\(4.50\)
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what is the molar mass of ch2cl2? 1 mol c = 12.01 g c 1 mol h = 1.008 g…
\(84.93\)
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determine the number of particles in the 0.28 mol sample of babr₂. 1 mo…
Coefficient: \(1.69\), Exponent: \(23\)
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given 83.2 g of babr₂, determine the number of moles of babr₂. 1 mol ba…
\(0.28\)
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what is the molar mass of babr₂? 1 mol ba = 137.33 g ba 1 mol br = 79.9…
\(297.13\)
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how many molecules are in 2.0 moles of co₂? ? × 10^? molecules of co₂ r…
Coefficient: \(1.2\) (rounded from \(1.204\) considering significant figures, since \(2.0\) has two significant figures), Exponent: \(24\)
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how many formula units are in 3.0 moles of sb2s3? ? × 10^? formula unit…
Coefficient: \(1.8\), Exponent: \(24\)
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how many molecules are in 0.8 moles of no2? ? × 10^? molecules of no2 r…
Coefficient: \(4.816\), Exponent: \(23\)
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what is the mass of 0.25 mol of koh? molar mass koh = 56.11 g/mol 0.25 …
\(14.0275\space g\)
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what is the mass of 1.5 mol of nacl? molar mass nacl = 58.44 g/mol 1.5 …
$87.66\space g$
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7. a 3.69 g sample of sodium sulfate, na₂so₄, is dissolved in enough wa…
B. \([Na^{+}]=3.46\times10^{-2}M\), \([SO_{4}^{2 - }]=1.73\times10^{-2}M\)
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what will happen if you add more solute to a saturated solution? it wil…
It will remain undissolved in the container.
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what is the mass of 5.7 mol of nh3? molar mass nh3 = 17.04 g/mol 5.7 mo…
\(97.128\space g\)
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3 points possibles écrivez léquation de dissociation électrolytique ou …
a) \(P_{2}O_{5}(s) ightarrow P_{2}O_{5}(aq)\) b) \(CaCl_{2}(s) ightarrow Ca^{2 +}(aq)+2Cl^{-}(aq)\) c) \(Al_{2}S_{3}(s) ightarrow 2Al^{3 +}(aq)+3S^{2 -}(aq)\)
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select all the mixtures. carbon dioxide pudding nickel water vapor
Pudding.
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which item is a pure substance? ○ sugar ○ ocean water ○ iced tea ○ a pe…
sugar
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select all the mixtures. salt water chocolate bar cracker wood
salt water
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lesquelles des équations de dissociation électrolytique ou moléculaire …
# Explications brèves: - **a)** \( \text{PCl}_{3(g)} ightarrow \text{PCl}_{3(l)} \) n'est pas une équation de dissociation électrolytique. C'est une équation de changement d'état …
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what is a pure substance that contains only one atom called? an element…
an element
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5. explain how the model you developed shows that when oxygen combines …
The model represents a balanced chemical equation. In \(2H_2+O_2 ightarrow 2H_2O\), the number of hydrogen atoms: \(2\times2 = 4\) (reactants) and \(2\times2 = 4\) (products). The…
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select the two mixtures. 24 - karat gold sugar silver and glass balls l…
silver and glass balls, lava
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1 point possible laquelle des molécules ci-dessous ne peut exister? coc…
d) \(CaS_2\)
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window cleaner is ammonia dissolved in water. what is this an example o…
a solution
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what is the water referred to as in a solution of a carbonated beverage…
a solvent
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how many grams of potassium chloride, kcl, are required to prepare 500.…
E. 55.9 g
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vocabulary & key pure substances & mixtures 1. which of the following q…
1. A. Element, B. Compound, E. Any substance containing all identical molecules, G. Water 2. C. Heterogeneous Mixture, D. Solution, F. Any substance containing more than one type …
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what is the molarity of a solution made by dissolving 22.5 g of glucose…
A. \(3.52\space M\)
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formation of water reaction check answers
The chemical equation \(2H_2+O_2 ightarrow2H_2O\) is balanced as the number of hydrogen and oxygen atoms is the same on both sides of the equation.
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formation of water reaction element oxygen hydrogen number of atoms bef…
1. \(2\) 2. \(2\) 3. \(4\) 4. \(4\)
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pour chacun des énoncés suivants, déterminez, selon le cas, la concentr…
a) \( 48,5\ g/L \) b) \( 1,875\ L \) c) \( 1,75\%m/V \) d) \( 1,75\%m/V \)
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pour chacun des énoncés suivants, déterminez, selon le cas, la concentr…
a) \( 48,5\ g/L \) b) \( 1,875\ L \) c) \( 0,68\ g \)
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a) une eau de javel a une concentration de 4,85% m/v. quelle est sa con…
48,5 g/L
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caffeine, a stimulant in coffee and tea has a molar mass of 194.19 g/mo…
C. \(C_8H_{10}N_4O_2\)
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soit les six solutions aqueuses suivantes. glissez ces solutions pour l…
Solution C ($0,85 g/L$) < Solution A ($1,5 g/L$) < Solution D ($1,55 g/L$) < Solution B ($2,5 g/L$) < Solution E ($12 g/L$)
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dans une municipalité, la concentration maximale acceptable des ions ni…
B. \(2,5\ mg\)
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what is the empirical formula of a compound containing 49.97% carbon, 1…
A. $C_{2}H_{5}F$
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reliez chaque situation de la colonne de gauche à la concentration en p…
a) \( C = 0,01\ ppm\) b) \( C = 600\ ppm\) c) Erreur d'énoncé probable (si c'est une solution avec \( V\) non - donné. Si c'est la composition du médicament (solide) : \( C=\frac{…
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reliez chacune des situations de la colonne de gauche à la concentratio…
# Explanation: ## Step1: Calculer la masse volumique de l'eau La masse volumique de l'eau est donnée : $ ho = 1\ g/mL = 1000\ g/L= 1\ kg/L$ ## Step2: Formule de la concentration e…
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2. what is the percent by mass of carbon in ( c_{10}h_{14}o )? (( c_{10…
E. \(79.96\%\)