Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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a chemist mixes 4 liters of one acid solution with 10 liters of a 40% s…
\(0.05\)
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1 multiple choice 20 points which human activity can increase greenhous…
1. C. Driving cars that use gasoline. 2. A. Use fewer pesticides and fertilizers on crops.
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its when one relates similar objects to schemas one is already familiar…
D. Assimilation
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in hydrogen peroxide (h₂o₂), which option best shows how the atoms are …
\(H - O - O - H\) (the second option in the given choices)
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forms of energy and energy transformations practice lt. i can identify …
1. h. Gravitational 2. e. Nuclear, c. Electromagnetic (radiant) 3. g. Elastic 4. d. Chemical 5. b. Electric 6. e. Nuclear 7. f. Sound 8. j. Thermal (heat) 9. d. Chemical 10. d. Ch…
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chemical equations quick check methanes chemical formula is ( ch_4 ). i…
No, there is not because carbon needs four bonds, so it bonds with each hydrogen atom; hydrogen only forms one bond.
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chemical equations quick check use your knowledge of valence electrons …
O=C=O
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methanes chemical formula is ch₄. is there a bond between any of the hy…
No, there is not because carbon needs four bonds, so it bonds with each hydrogen atom; hydrogen only forms one bond.
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use your knowledge of valence electrons and how they affect bonds to fi…
B. \(O = C = O\)
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how do valence electrons impact the type of bonds an atom makes? (1 poi…
An atom wants a full outer shell of valence electrons, so it will either transfer or share electrons depending on what the other atom needs.
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chemical equations quick check how do valence electrons impact the type…
An atom wants a full outer shell of valence electrons, so it will either transfer or share electrons depending on what the other atom needs.
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chemical equations quick check how many electrons does hydrogen have in…
two
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alice and julios company makes protective coverings for off - roading v…
Alice works with natural rubber, and Julio works with vulcanized rubber.
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waters solid state is than its liquid state. more dense less dense more…
less dense
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when water in the atmosphere changes form from a vapor to a liquid, for…
condensation
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question 6 raising the temperature of water requires a lot of energy du…
high heat capacity
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which of the following are biogeochemical cycles that rely on the water…
carbon cycle, nitrogen cycle, phosphorous cycle
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sari is studying four different samples of materials. this table shows …
X
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sal drew the electron dot diagram of an aluminum atom as shown. how sho…
He should add one dot below and one dot to the left of the symbol.
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water is said to be the ________________________ because it easily diss…
universal solvent
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what term describes the transition of water from a liquid to a gas? vap…
vaporization
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my grandmothers cookies by a gautam she bakes and she forgets she eats …
C. The line breaks in each stanza cause the reader to pause.
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by a gautam she bakes and she forgets she eats and she forgets my grand…
C. The line breaks in each stanza cause the reader to pause
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in the lab, where curious minds abound a science experiment, a tale to …
A. \(ABA, ABA, ABA, ABA, ABA, ABAA\)
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based on its location on the periodic table, which metal is likely to b…
C. magnesium (Mg)
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36) what type of bond is being represented here? a. ionic bond b. coval…
a. Ionic Bond # 37)
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31) what type of bond is formed between sodium and chlorine in table sa…
- 31) A. Ionic Bond - 32) D. They involve the transfer of electrons - 33) B. Aluminum bromide - 34) D. They are equally strong - 35) A. Atoms are stable with eight electrons in th…
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which refers to the type of chemical bond that involves the transfer of…
Ionic
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question 8 (3 points) ......is anything that has mass and takes up spac…
B. Matter
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which natural polymer makes up paper? o starch o nylon o wool o rubber
starch
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which compound contains only nonpolar covalent bonds? no₃ hcl o₂ h₂o
\(O_{2}\)
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which element has the fewest valence electrons available for bonding? i…
# Explicaciones breves: Para determinar el número de electrones de valencia de un elemento, se puede utilizar la tabla periódica. Los electrones de valencia son los electrones en …
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question 7 (3 points) states that in all physical or chemical changes, …
B. The first law of thermodynamics
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which pair of elements will form a covalent bond? zinc and bromine hydr…
hydrogen and chlorine
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which structure shows the correct electron arrangement in ccl₄?
La segunda estructura (aquella que muestra cuatro átomos de cloro unidos al carbono y cumpliendo la regla del octeto para cada átomo).
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a solid compound in a sealed container was kept at a very low temperatu…
a covalent compound because it has a low melting point
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which statement about covalent compounds is true? they have strong inte…
They are poor conductors of heat.
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which is a property of covalent compounds? they ionize in solution. the…
They have a low boiling point.
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which type of bond will most likely be found in hbr given that the elec…
# Explicación breve: Para determinar el tipo de enlace en HBr, calculamos la diferencia de electronegatividad ($\Delta EN$) entre H ($EN = 2.20$) y Br ($EN = 2.96$). $$\Delta EN=|…
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17) what type of elements are known to be able to conduct heat and elec…
17. B. Metalloids 18. A. Metals 19. C. Electrons 20. B. 20
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who had a theory of the atom, prior to dalton? proust democritus lavois…
Democritus
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16) true or false: a jar of both carbon monoxide (co) and carbon dioxid…
A. True
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10) what is a solution? a. a mixture of two solids b. a suspension of p…
10. d. A homogeneous mixture of two or more substances 11. b. Solubility 12. c. Amount that can dissolve vs. Temperature 13. c. Tap water with a spoonful of NaCl
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6) when a substance undergoes a physical change, there will be a rearra…
- 6) b. False - 7) c. Suspension - 8) d. Anything that has mass and occupies space - 9) a. Physical change
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an atom has 105 neutrons and 96 protons. calculate the mass number of t…
201
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an atom has 25 neutrons and 14 protons. calculate the mass number of th…
39
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an atom has 6 neutrons and 5 protons. calculate the mass number of the …
11
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which set of atoms has the shortest bond length? n≡n n=n n−n
\(N\equiv N\) has the shortest bond length.
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ancient mesoamerican rubber they also needed to know how to create spec…
B. the two liquids
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an atom has 13 neutrons and 12 protons. calculate the mass number of th…
25
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what is the bond strength of a single bond compared to a triple bond? y…
C. A single bond is weaker than a triple bond.
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which bond is the strongest?
C
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an atom has a mass number of 90 and 45 protons. calculate the number of…
45
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an atom has a mass number of 7 and 2 protons. calculate the number of n…
5
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an atom has a mass number of 35 and 16 protons. calculate the number of…
19
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an atom has a mass number of 24 and 12 protons. calculate the number of…
12
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which bond is the weakest?
A
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1) the kinetic molecular theory (kmt) states that: a. as energy (temper…
a. As energy (temperature) increases, so does the particle speed 2.
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how many electrons are shared in a single bond? 4 6 2 1
2
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physical science six week units 1a, 1b, and 2a: 1) the kinetic molecula…
1. a. As energy (temperature) increases, so does the particle speed. 2. b. Flammability. 3. a. pH. 4. d. A compound.
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the periodic table is a disorganized way to group elements based on the…
False
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multiple choice questions question #1 according to the text, what are l…
- Question #1: B. Explaining the arrangement of atoms and electrons in molecules. - Question #2: B. To form stable electron configurations. - Question #3: C. A bond that involves …
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why can salad bars and buffets be unsafe? the food is refrigerated, slo…
The food may be exposed to the air for a long time, letting bacteria reproduce.
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in a restaurant, eat ______ and include food from all food groups. fres…
fresh choices
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natural gas is formed from marine mud. what is the primary component of…
Methane
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10) choose the best answer. the scientific community uses the ______ sy…
10) Kelvin 11) Geothermal
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the number of moles is calculated by dividing mass by
molar mass
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if you have 2 moles of a substance, you multiply by the molar mass to f…
mass of the substance
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read this excerpt from a passage and the references entry for the sourc…
This source is not credible because anyone can post or edit information on Wikipedia, whether or not they have expertise in the subject.
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the molar mass of carbon (c) is g/mol. the molar mass of oxygen gas (o₂…
12.01; 32.00
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the molar mass of sodium chloride (nacl) is
$58.44\ \text{g/mol}$
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the molar mass of carbon dioxide (co₂) is
\(44.01\space g/mol\)
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what mass of cl₂ reacted when 0.243 g mg reacted completely to form 0.9…
\(0.710g\ Cl_2\) (the third option)
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the molar mass of water (h₂o) is approximately
\(18\space g/mol\)
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what mass of nacl formed when 0.25 g na react completely with 0.39 g cl…
\(0.64\space g\space NaCl\) (the fourth option)
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convert: 1,000 milligrams = grams submit
\(1\)
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what property of a metal does the image represent? malleability electri…
electrical conductivity
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the atomic mass listed for an element on the periodic table does not ta…
B. False
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a measurement was taken three times. the correct measurement was 68.1 m…
a) neither b) both c) precise d) neither
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what does it mean for electrons to be delocalized in metals? the valenc…
The valence electrons move around freely between the metal cations.
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what is the formula for magnesium nitride? n₃mg₂ mg₃n₂ mgn mg₂n₃
\(Mg_3N_2\)
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what is the formula for copper(ii) oxide? co₂ cu₂o cuo cuco₄
CuO
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the term nucleons refers to the components that make up the nucleus of …
True
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what is the formula of barium phosphate? bahpo₄ ba₃p₂ ba₃(po₃)₂ ba₃(po₄…
\(Ba_{3}(PO_{4})_{2}\)
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a fuel cell is an electrochemical device that combines hydrogen and oxy…
a. Water
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what is the name of this ionic compound? snco3 tin (ii) carbonate tin (…
tin (II) carbonate
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what polyatomic ion is present in the following formula? kmno4 ammonia …
Permanganate
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what is the formula for the hydroxide ion? oh⁻ ho⁺ h₂o h₂⁻
OH⁻
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which of the following elements does not form more than one ion? zn ni …
Zn
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what is the charge on the lead in lead(iv) iodide? -1 +4 +2 -4
B. +4
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name the following ionic species. bas barium sulfide boron sulfide boro…
barium sulfide
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name the following ionic species. naf sodium monofluorine sodium monofl…
sodium fluoride
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what is the correct formula for the ionic compound that would result fr…
\(Na_{2}S\) (the fourth option in the given choices)
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what is the formula for the ionic compound formed by calcium and nitrog…
\(Ca_3N_2\)
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at what temperature does water turn from liquid to steam? 50°f 0°f 212°f
\(212^{\circ}F\)
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69.describe the requirements for an effective food safety training prog…
69. c. Include topics on personal hygiene, safe food handling, and cleaning procedures. 70. c. Ensure it's appropriate for the surface and use as directed. 71. c. Low water activi…
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what is the electrolyte capacity (ability to conduct) when an ionic com…
strong electrolyte
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which of the following is a property of ionic compounds? high boiling p…
high boiling point
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56. what are the guidelines for food handlers who are diagnosed with a …
56. d. Bury waste in a compost pit. 57. b. Serve them the regular menu items. 58. d. Refuse critical factors for ensuring the safety of food during transport for catering or deliv…
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which image depicts the ionic compound formed between calcium and sulfu…
C.