Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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how many electrons will selenium need to gain or lose to be left with a…
gain 2
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how many valence electrons does neon have? * :ne: 1 2 3 4 5 6 7 8
8
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the octet rule states that most atoms will attempt to fill their outer …
8 electrons
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how many valence electrons does carbon have? 1 2 3 4 5 6 7 8 the octet …
D. 4
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the most dots that can be represented in a lewis diagram is: * valence …
8
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how many electrons will magnesium need to gain or lose in order to have…
1. B. lose 2 2. A. lose
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how many electrons will lithium need to gain or lose to be left with a …
lose 1
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name of the element period number of the element symbol of the element …
B. Sodium
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how many electrons will nitrogen need to gain or lose to be left with a…
C. gain 3
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how many electrons will phosphorus need to gain or lose to be left with…
gain 3
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how many valence electrons does sulfur have? *
6
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which element does this bohr model represent? * o beryllium o carbon o …
A. Beryllium
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valence electrons and lewis dot structures • valence electrons are repr…
only the valence electrons
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an element in group 3 will have? valence electrons. 1 2 3 4 5 6 7 8
3
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which element does this bohr model represent? * p - 10 n - 10 fluorine …
1. Neon 2. gain
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which of the following is a false statement? * lewis dot structures are…
First question: Rows/periods on the Periodic Table are used to identify the number of valence electrons in atoms. Second question: 7
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atoms will try to gain or lose the ? number of electrons possible in or…
1. B. least 2. D. 4
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diagrams that are used to represent valence electrons: dot to dot struc…
1. C. Lewis dot structures 2. B. Silicon
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the _ will identify how many valence electrons for an atom. * period nu…
1. B. group number 2. A. lose 1
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the outermost electrons in an atom are * o valence electrons. o make th…
1. valence electrons 2. A full outer shell of electrons
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how many electrons will oxygen need to gain or lose to be left with a f…
B. gain 2
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determine the number of protons, neutrons and electrons in potassium 19…
$p^{+}:19$, $n^{0}:20$, $e^{-}:19$
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which of the following is a true statement? * 2 points rows/periods on …
Groups/columns on the Periodic Table are used to identify the number of valence electrons in main group elements.
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what are valence electrons? valence electrons are the outermost electro…
6
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6. determine the number of protons, neutrons and electrons in the follo…
For potassium ($K$): $p^+=19$, $n^0 = 20$, $e^-=19$ For tellurium ($Te$): $p^+=52$, $n^0 = 76$, $e^-=52$
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rule that explains the need for atoms to have 8 electrons in its outer …
E. Octet Rule
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6. determine the number of protons, neutrons and electrons in the follo…
Potassium ($K$): Protons: 19, Neutrons: 20, Electrons: 19 Tellurium ($Te$): Protons: 52, Neutrons: 76, Electrons: 52
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how many electrons will bromine need to gain or lose in order to have a…
gain 1
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how many electrons will nitrogen need to gain or lose in order to have …
C. gain 3
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multiple - choice question ionic compounds are not soluble, and the sol…
are soluble, and the solution conducts electricity
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multiple - choice question what kind of bond is formed by the transfer …
B. ionic bond
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multiple - choice question based on coulombs law, which would you expec…
MgS
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multiple - choice question a bond between a positive ion and a negative…
B. an ionic bond
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multiple - choice question what type of ion do metals form? anions cati…
B. cations
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multiple - choice question when are most atoms stable? when they have 1…
None of the provided options are correct. Most atoms are stable when they have 8 valence electrons (except hydrogen and helium which follow different rules for stability).
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multiple - choice question what is a polar covalent bond? electrons mor…
Electrons more attracted to one atom causing a negative charge and positive charge within a molecule.
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multiple - choice question what are electrons that are not bonded calle…
B. Lone pairs
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multiple - choice question in a lewis dot structure, what is represente…
B. Valence Electrons
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multiple - choice question what is electronegativity? how much energy i…
The ability of an atom to attract a shared pair of electrons
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multiple - choice question what is electronegativity? how much energy i…
- For "What is electronegativity?": The ability of an atom to attract a shared pair of electrons. - For "In a Lewis dot structure, what is represented by dots?": Valence Electrons
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multiple - choice question what type of bond results from sharing elect…
covalent bond
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bent = electron geometry molecular geometry tetrahedral= molecular geom…
1. molecular geometry 2. electron geometry 3. molecular geometry 4. electron geometry
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multiple - choice question what happens when atoms get too close to eac…
Their nuclei repel each other
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match the correct bonding symbol to the description of the position of …
H is in the front of the paper; bond points toward the viewer.
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match the correct bonding symbol to the description of the position of …
For N - H with solid - wedge: H is in the front of the paper; bond points toward the viewer For S - H: H is in the plane of the paper; bond is also in the plane of the paper
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multiple - choice question where are the electrons in a covalent bond? …
C. Between the nuclei
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fill in the blanks with the number of valence electrons that each atom …
Si = 4 H = 1 S = 6 Br = 7 Ca = 2 N = 5
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multiple - choice question what connects chemical bonds? all of the abo…
B. Electrons
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question 6 of 10 not yet answered points possible: 0.50 determine wheth…
Tetrahedral CCl₄: Non - polar Linear CS₂: Non - polar Trigonal pyramidal NH₃: Polar
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identify the molecular geometry around the nitrogen atom highlighted re…
Trigonal pyramidal
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multiple - choice question how do atoms achieve their lowest energy? ba…
Balancing attractive and repulsive forces
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question 3 match the scientist to his contributions. won a nobel prize …
Won a Nobel Prize for his discovery of plutonium and synthesis of neptunium: Glenn Seaborg Ordered the Periodic Table by increasing atomic number, died in WWI: Henry Moseley Order…
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unit conversion tutorial use the provided unit - conversion factors. ma…
8340
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a certain reaction is first order in n2 and second order in h2. use thi…
For the first blank: $2.56\times 10^{-3}M/s$ For the second blank: $7.22\times 10^{-5}M/s$
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exercise iv—inference complete the sentences by inferring information a…
1. mix the ingredients together. 2. troubled or harassed. 3. reading relevant books or materials.
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what creates the \space\ indicated in this \space filling\ model of wat…
constantly moving electrons
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consider a hypothetical chemical reaction: a + b → c + d (in this equat…
What is the heat of reaction? -50 kJ/mol Is the reaction exothermic or endothermic? Exothermic Can you determine the activation energy? Yes, it's 200 kJ/mol Can you determine the …
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consider a hypothetical chemical reaction: a + b → c + d (in this equat…
What is the heat of reaction? 50 kJ/mol Is the reaction exothermic or endothermic? Endothermic Can you determine the activation energy? Yes, it's 250 kJ/mol Can you determine the …
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consider a hypothetical chemical reaction: a + b → c + d (in this equat…
What is the heat of reaction? -200 kJ/mol Is the reaction exothermic or endothermic? Exothermic Can you determine the activation energy? Yes, it's 100 kJ/mol Can you determine the…
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check your understanding 1. name each of the following ionic compounds:…
1. - (a) Magnesium bromide - (b) Potassium hydrogen sulfate - (c) Ammonium phosphate - (d) Calcium hydroxide 2. - (a) Carbon tetrafluoride - (b) Phosphorus trihydride (phosphine) …
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honors chemistry—unit 2 video guide the race for absolute zero answer t…
1. Refrigerators, freezers, MRI machines. 2. Antarctica; about - 128.6°F (- 89.2°C). 3. Scottish chemist and physicist; Dewar flask. 4. Resisted liquefaction due to low boiling po…
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question 3 5 points which of the following is true about air molecules …
B. The density of air molecules decreases as pressure decreases
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use the drop - down menus to make the following statements correct. all…
The used plastic pipets will be: collected in a specific solid waste container.
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question 1 5 points the ideal gas law tells us that: a warm air is more…
B. Warm air parcels rise and cool air parcels sink because of differences in density.
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a student analyzes a solution for color and obtains the following graph…
500 nm
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the function ( f(x)=\frac{6.5x^{2}-63.8x + 2102}{x^{2}+324}) models the…
5.5 (estimated value from the graph to the nearest tenth)
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the function (f(x)=\frac{8.5x^{2}-84.2x + 3740}{x^{2}+678}) models the …
4.8
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why couldnt mendeleev organize the entire table during his research? th…
C. Some elements were undiscovered at the time
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what are the basic building blocks of matter? compounds molecules elect…
D. atoms
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what happens when aluminum fills its valence shell? three electrons are…
Three electrons are lost, creating Al³⁺
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what is group 18 of the periodic table called? metals noble gases nonme…
B. noble gases
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select a word from the drop - down menu to correctly complete the state…
group
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dehydration synthesis in each example of dehydration synthesis, show ho…
For the synthesis of a fat: 1. Box around the $H$ from glycerol's $-OH$ group and the $OH$ from the fatty - acid's $-COOH$ group for each of the three reactions. 2. The structural…
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determine the quantity of bromine atoms in 18.0 grams of hgbr₂
$6.02\times 10^{22}$
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select the text from the paragraph that best helps you understand that …
"ushered in an era of greater awareness, leading people to start thinking more carefully about the environmental impact of chemical products"
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select the text from the paragraph that best helps you understand that …
Proponents of DDT usage pointed to the pesticide as a cost - effective means of controlling mosquito populations in parts of the world with high malaria rates
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question 11. use the periodic table to identify the group number and pe…
| Element Name | Group Number | Period Number | | ---- | ---- | ---- | | Neon | 18 | 2 | | Rubidium | 1 | 5 | | Iron | 8 | 4 | | Phosphorus | 15 | 3 | | Lead | 14 | 6 | | Hydrogen…
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question 42(multiple choice worth 3 points) (01.02a mc) which of the fo…
B. Unsaturated fatty acids
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question 38(multiple choice worth 3 points) (01 02a mc) polymers are fo…
Assembling molecules in either hydroxyl or carboxyl functional groups
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review: 1. chemical properties 2. neutron 3. proton 4. physical propert…
1. b 2. d 3. e 4. c 5. a 6. b 7. c 8. b 9. d 10. b
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question 36(multiple choice worth 2 points) (02.01 mc) which of the fol…
The positive and negative charges of the water molecule pull on the negative and positive ends of the ionic molecule to break them apart.
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what part of an ions symbol indicates its charge?
The superscript written after the element's symbol.
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3. observe: click reset (?). the electrons in the outermost orbit, call…
1; Li•
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vocab: atom: the smallest piece of matter that still retains the proper…
ionic bond: A chemical bond formed by the electrostatic attraction between oppositely - charged ions. covalent bond: A chemical bond involving the sharing of electron pairs betwee…
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2. analyze. electrons are arranged in orbits called energy levels. the …
A. 2 B. 8 C. 8
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2. which particles are produced by different types of bonding? -
Ions (in ionic bonding), molecules (in covalent bonding), delocalized electrons (in metallic bonding)
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activity b: electron arrangements question: how are electrons arranged …
Electrons are arranged in energy - levels (shells) around the nucleus, filling lower - energy levels first.
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how does the mass of a molecule affect the rate of diffusion? the heavi…
The lighter the molecule, the faster the rate of diffusion.
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4.2 - combination of atoms (notes) review questions: 1. what are ionic …
1. Ionic bonds are formed by the transfer of electrons between atoms creating positive and negative ions that attract each other. Covalent bonds are formed by the sharing of elect…
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which statement about compounds is true? compounds are simpler than ele…
A compound has different properties than the elements from which it is made.
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which of the following is a bond between two molecules? o a chemical bo…
a chemical bond in which no electrons are shared
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creating ions problem 6.2 - enhanced - with feedback correct the number…
6
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state the number of electrons that are gained by atoms of each of the f…
1
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list the three types of chemical bonds and describe each type of bond. …
1. Ionic bond: Formed by electron - transfer between atoms creating ions that attract. 2. Covalent bond: Atoms share electrons to gain stable electron - configuration. 3. Metallic…
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sodium (na) is a _______ * 2 points alkalai metal nonmetal noble gas me…
1. A. alkali metal 2. C. 20 3. D. Noble Gas
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what kind of charge does an ionic compound carry? * 2 points neutral po…
1. neutral 2. polar covalent bond 3. nonpolar covalent bond
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use the passage to answer the question. how does the author use details…
By providing evidence from a scientific study.
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in a covalent bond, electrons are __________. * 2 points shared lost ga…
1. A. shared 2. C. sodium chloride 3. B. sodium
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the average atomic mass is equal to the number of neutrons in an atom. …
1. B. False 2. A. True
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molecule or ion,number of valence electrons,total number of atoms and s…
| Molecule or ion | Number of valence electrons | Total number of atoms and sets of lone pairs surrounding central atom(s) | Structure geometry (name) | |---|---|---|---| | CCl₄ |…