Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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the reduction catalyst in a catalytic converter helps to: o a. reduce t…
a. Reduce the oxides of nitrogen molecules into their base compounds.
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is/are created when raw fuel evaporates into the atmosphere or when it …
d. Hydrocarbons
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carbon monoxide is a colorless, odorless, tasteless,______, and highly …
A. Flammable
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10. most pregnant women take these to make sure they are getting all th…
10. C. supplements 12. C. alcohol 13. D. Fetal Alcohol Syndrome 16. B. Fetal Alcohol Syndrome 17. C. nutrients and oxygen 18. D. smoking
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10. most pregnant women take these to make sure they are getting all th…
10. c. supplements 11. have withdrawal symptoms, be irritable, don't sleep well, cry a lot 12. c. alcohol 13. d. Fetal Alcohol Syndrome 14. malformed skeleton, death, attention de…
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write the entire configuration for each of the following atoms. 1. sulf…
1. \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{4}\) 2. \(1s^{2}2s^{2}2p^{3}\) 3. \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}4p^{6}5s^{2}4d^{10}\) 4. \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{…
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what is the name of the group that contains the second most reactive me…
1. Alkaline earth metals. 2. Up.
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se: if the statement is true, write true in the blank. if it is false, …
1. false, number of solute particles 2. true 3. false, increases 4. true 5. false, lower 6. true
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name: ela buzz check the box next to the comma splice. □ if you have se…
- Comma splice: Check the box next to "I didn't use to have allergies, I do now". Fix: I didn't use to have allergies, but I do now (or other valid fixes like using a semicolon). …
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as amanda analyzed the audience for her speech about organic foods, she…
- First question: C. demographic - Second question: B. group membership of your audience
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room a: maintained at 18°c (64°f) room b: heated to 28°c (82°f) in each…
A. The scent will spread faster and farther in the warm room.
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label the image with the options given below energy diagram potential e…
- Energy of the reactants: The starting horizontal line (e.g., if we assume the first horizontal segment at a certain \(y\) - value on the potential energy axis). - Activation ene…
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unit 1, lc2 practice balance the following chemical equation: this is a…
\(3Li+1AlCl_3 = 3LiCl+1Al\), single replacement reaction.
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balance the equation: na + o₂ → na₂o this is an example of a reaction.
\(4\) \(Na+1\) \(O_2 = 2\) \(Na_2O\), synthesis reaction.
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unit 1, lc2 practice balance the following chemical equation: this is a…
\(1C_3H_8+5O_2 ightarrow3CO_2 + 4H_2O\), combustion reaction.
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when silver oxide (ag₂o) is heated, a reaction occurs and oxygen (o₂) a…
Balanced Equation: \(2Ag_2O = O_2 + 4Ag\); This is an example of a decomposition reaction.
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unit 1. lc2 practice when a chemical equation is balanced, this means t…
the same as
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in a chemical reaction, the products have chemical properties compared …
different
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which of these is not evidence that a chemical reaction has taken place…
solids dissolving in liquid
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unit 1, lc2 practice which of these is an example of a chemical change?…
bananas turning brown as they ripen
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carbon (c) is one of the most abundant elements on earth and is a criti…
Carbon has 6 protons, 6 electrons, and 6 neutrons.
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5. calculate the empirical formula of a compound that is 62.1% c, 13.8%…
The empirical formula of the compound is \(C_{3}H_{8}N\)
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fill in the blanks to explain how different forms of energy are related…
During a fireworks display, chemical energy stored in the fireworks is converted to light energy (what we can see) and sound energy (what we can hear). The reactions in the firewo…
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carbon (c) is one of the most abundant elements on earth and is a criti…
Protons: \(6\), Electrons: \(6\), Neutrons: \(6\)
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what determines whether and how much an atom will react with another at…
the number of outermost electrons
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match the subatomic particle to its proper location. protons neutrons e…
- Protons: in the nucleus of the atom - Neutrons: in the nucleus of the atom - Electrons: in shells or orbits around the nucleus
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the image below represents the periodic table of elements. atoms in the…
Column.
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question 2 which is the most reactive non - metal? chlorine fluorine he…
Fluorine
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4. calculate the empirical formula of a compound that is 67.6% hg, 10.8…
The empirical formula of the compound is \(HgSO_{4}\)
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question 1 1 pts which is the most reactive metal? lithium francium rad…
Francium
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calculate the molar mass of ammonium carbonate. a 96.09 g/mol b 112.09 …
A. \(96.09\ g/mol\)
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how many atoms are in 1.50 moles of fluorine gas? a 18.98 b 6.022 × 10²…
C. \(1.81\times 10^{24}\)
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4. calculate the empirical formula of a compound that is 67.6% hg, 10.8…
The empirical formula of the compound is \(HgSO_{4}\)
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unit 1, lc1 practice match each subatomic particle with its correct cha…
electrons: negative; neutrons: neutral; protons: positive
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determine the correct empirical formula of a compound containing 26.68%…
D. \(CHO_{2}\)
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how are elements arranged on the periodic table? randomly by atomic num…
By atomic number.
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one half of a mole of atoms would contain how many atoms? a $3.011×10^{…
A. \(3.011\times 10^{23}\)
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you have 10.0 g each of na, c, pb, cu and ne. which contains the larges…
D. C
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what is the formula of the compound between calcium and sulfur that has…
A. $CaS$
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question 10 (1 point) atomic radius increases as you move down a group …
False
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question 9 (1 point) electronegativity increases as you go across the p…
True
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how many moles are there in 17.5 grams of sodium? a 0.761 b 22.99 c 1.0…
A. 0.761
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question 8 (1 point) how many dots would be placed around the lewis dot…
B. 2
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question 1 1 point a 15.5 gram sample of diphosphorous pentoxide contai…
B. 6.76
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question 7 (1 point) what element is represented by the electron config…
B. Potassium (K)
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question 6 (1 point) what is determined by the proton(s) of an element?…
d. Atomic number of the element
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question 5 (1 point) what is determined by the electron? mass of the el…
d. Chemical properties of the element
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question 4 (1 point) which of these below has 74 protons and 73 electro…
C. \(W^{1+}\)
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question 3 (1 point) which of these below has 16 protons and 18 electro…
A. \(S^{2-}\)
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question 2 (1 point) an atom with an atomic number of 8 and a mass numb…
C. 8 protons, 8 electrons, 7 neutrons
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question 1 (1 point) an atom with an atomic number of 31 and a mass num…
B. 31 protons, 31 electrons, 41 neutrons
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during an experiment, a student observes the formation of a precipitate…
A. A solid forms, and there is a change of color.
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credibility isnt just about evaluating individual articles. it is also …
- The article does not mention that its publisher is owned by one of the food corporations mentioned in the story: Less credible. - The author only quotes research that supports o…
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when sodium metal is added to water, an orange flame is observed on the…
C. A chemical reaction occurs because heat and light are given off
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the chemical formula below shows how salt is produced. hcl + naoh → nac…
C. \(HCl\) and \(NaOH\)
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burning a piece of wood in fire can be best described as a chemical cha…
chemical change because the atoms in wood and oxygen are rearranged.
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the images show two processes. image a: a roasting marshmallow image b:…
Image A shows a chemical reaction, and image B shows a physical change.
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a piece of limestone erodes due to acid rain. this process can be best …
slow chemical change.
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consider the chemical equation of the combustion of methane. sort the c…
- Reactants: \(CH_{4}\), \(O_{2}\) - Products: \(CO_{2}\), \(H_{2}O\)
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gardening, whether it involves flowers or food, is a popular activity. …
B. general
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when considering sources of air pollution, v.o.c is the acronym for whi…
Volatile Organic Compounds
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ozone the pollutant and sulfuric acid are pollutants that are not relea…
Secondary pollutant
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vocs are air pollutants. what does voc stand for? very odd contaminants…
Volatile Organic Compounds
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which statement primarily appeals to logos, or reason, to support the p…
While it is true that electives may not be explicitly academic, in reality, electives can still help students develop valuable skills, such as critical thinking and creativity.
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which of the following statements about electron affinity are true? sel…
- An atom with a higher electron affinity will release a greater amount of energy. - Electron affinity is the energy change that occurs when an atom gains an electron. - For the m…
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which of the molecules has the highest boiling point? liquid 2: ch₃ch₃ …
Liquid 4: \(CH_3CH_2CH_2CH_3\)
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the periodic table is arranged based on repeating chemical properties o…
Arranged in order on the periodic table: atomic mass, electron configuration Not arranged in order on the periodic table: elemental color, chemical symbol
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how many valence electrons are lost by the metallic element when formin…
2
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storyline 1 exam write the name of the element with the electron config…
carbon
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which pair of words correctly completes the statement? alkali metals ar…
reactive, lose 1 electron
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bcl₃ is the product of boron and chlorine atoms. what is the name of th…
boron trichloride
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storyline 1 exam 62 of 73 copper is a metal and has a cu2+ ion that rea…
1 copper and 2 bromine.
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storyline 1 exam what did the bohr model assume about the motion of ele…
All electrons move in a circular orbit around the nucleus.
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how can a scientist determine the strength of the intermolecular forces…
by determining and comparing the electronegativity of the atoms in the compound, by heating the substance and identifying the temperature at which it undergoes a phase change
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storyline 1 exam a mystery element has 18 protons. which one of the fol…
The element belongs in row 3 of the periodic table and is classified as a noble gas.
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the list identifies various properties of four elements: element 1 is a…
Elements 2 and 4
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storyline 1 exam which arrangement of the following period 5 elements, …
Te, Sb, In, Sr, Rb (the second option in the given choices)
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each arrow shows an electron moving from one energy level to another. w…
A. only C (incorrect) B. B and C (incorrect) C. only A (incorrect) D. A and D (incorrect) Wait, there is a mistake above. Actually, for transition A: if we assume the numbering (1…
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storyline 1 exam a calcium ion is formed from a calcium atom. how do th…
The calcium ion is smaller than the calcium atom because the same number of protons now attract a fewer number of electrons.
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name two elements that have similar properties based on their groupings…
Na and Li
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oxygen reacts with many different elements to form different molecules.…
NO (g), CO (g)
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storyline 1 exam which characteristic is not a periodic trend? o atomic…
number of elements in a group
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which of the following statements about the properties of elements rela…
B. The light that an element emits is made up of a limited number of narrow lines of light that produce a unique pattern or atomic emissions spectrum for that element. D. An atomi…
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storyline 1 exam 44 of 73 an atom of bromine has 35 electrons. these el…
\(2,8,18,7\)
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fill in the blank question if ionic bonds occur between metals and the …
oxides; salts
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read the passage and answer the next two questions. during a classroom …
Ca, it belongs to Group 2.
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14. use complete sentences to answer this question. landfills are a way…
14. We can reduce the amount of waste going into landfills by recycling, composting organic waste, and reducing consumption. Recycling diverts materials from landfills, composting…
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fill in the blank question compounds that contain ionic bonds are need …
Ionic compounds
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e choice: write the letter of the correct choice in the blank. 7. which…
d. The rates of evaporation and condensation are equal.
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select all that apply which statements about the formation of ionic bon…
B. The oppositely charged ions attract each other in an ionic bond. C. A sodium atom transfers its valence electron to a chlorine atom.
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24. identify the weakest bond from the options listed below. a & c cova…
hydrogen bond
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22. materials that contain carbon are called: organics. carbonics. diss…
organics.
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18. all of the following are true of water except: water can dissolve m…
water is not the most common liquid on the planet, but it is the only substance that naturally occurs in all three states on Earth.
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what did president roosevelt do in 1906 that influenced the regulation …
He passed two laws: The Meat Inspection Act and The Food and Drugs act.
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what did president abraham lincoln do in 1862 to help influence food re…
He appointed the first chemist to serve in the Department of Agriculture.
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what is the main chemical is marijuana that has psychoactive or mind al…
THC
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7. when ice is melting, the heat being added causes: molecular motion t…
hydrogen bonds to break.
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6. hydrogen bonds: lower the heat capacity of water. make ice less dens…
make ice less dense than water.
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4. when water cools, but does not freeze, the molecules move______and t…
slower, less
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2. a(n)______is a substance of two or more atoms held together with che…
molecule