化學
化學反應、化學計量、分子結構與元素性質。
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how do chemical weathering, gas exchange, and limestone formation help …
- Carbon from the shells and exoskeletons of marine organisms can be stored underground in limestone for millions of years. This prevents excessive buildup of $CO_2$ in the atmosp…
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limestone is mostly made of sediment and the fossilized remains of anci…
gas exchange: Carbon moves from the atmosphere to the hydrosphere or from the hydrosphere to the atmosphere. chemical weathering: Carbon from the atmosphere interacts with the geo…
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limestone is mostly made of sediment and the fossilized remains of anci…
1. gas exchange: During this process, carbon dioxide dissolves into ocean water and forms carbonic acid, which breaks down into simple ions. This process can also happen in revers…
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active cycling of carbon sustains life on earth. it regulates climate, …
1. Carbon moves from the atmosphere to the biosphere. 2. Carbon moves from the geosphere to the atmosphere. 3. Carbon moves from the atmosphere to the hydrosphere. 4. Carbon moves…
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*86. oxygen and hydrogen react explosively to form water. in one reacti…
48 g
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76. apply concepts the law of conservation of mass was introduced in ch…
Dalton's atomic theory explains the law of conservation of mass as atoms are rearranged in reactions without being created or destroyed, thus mass is conserved.
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1. lis les indices et complète le tableau suivant. indices : 1. les élé…
# Explicación: ## Paso 1: Analizar la información de A A tiene 5 electrones de valencia en la tercera capa electrónica. Esto significa que A es un átomo del grupo VA y del período…
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question 4 where is a proton found in an atom? (1 word)
Nucleus
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question 1 the process of breaking and or forming chemical bonds is kno…
chemical reaction
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question 1 the process of breaking and or forming chemical bonds is kno…
chemical reaction
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draw the lewis structure for the disulfur monoxide (s₂o) molecule. be s…
The resonance structures of \(S_2O\) are \(S=\ddot{O}=S\), \(\overset{-}{S}-\overset{+}{O}\equiv S\) and \(\overset{+}{S}\equiv\overset{-}{O}-S\)
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question 1 the process of breaking and or forming chemical bonds is kno…
chemical reaction
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aspartame is an artificial sweetener that is 160 times sweeter than suc…
Molar mass of aspartame: $294.34\ g/mol$ Moles in 12.7 g: $0.0432\ mol$ Mass of 1.31 moles: $385.58\ g$ Molecules in 7.9 mg: $1.61\times 10^{19}\ molecules$ Nitrogen - atoms in 2.…
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draw the lewis structure for the ethylene (c₂h₄) molecule. be sure to i…
The Lewis structure of \(C_2H_4\) has a \(C = C\) double - bond with each carbon atom bonded to two hydrogen atoms (\(H - C - C - H\)) and there are no resonance structures.
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question 4 a _______ is used for determining the chemical composition o…
Question 4: C. spectrograph Question 5: D. refraction
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a sample of liquid heptane (c₇h₁₆) weighing 11.10 g is reacted with 1.3…
(a) $0\ mol$ (b) $0.7749\ mol$ (c) $0.1123\ mol$
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what do these two changes have in common? mixing glue and laundry powde…
Both are chemical changes.
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(7th) unit 3 - the atom directions: write neatly with pencil. answers d…
1. Atom 2. Protons, neutrons, electrons 3. Protons, neutrons 4. Outside the nucleus in electron shells 5. Positive; because it contains positively - charged protons and neutral ne…
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a sample of liquid heptane (c₇h₁₆) weighing 11.10 g is reacted with 1.3…
(a) 0 mol (b) 0.7749 mol (c) 0.1123 mol
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name the following compounds. (a) mg3(po4)2 name: (b) sf6 name: sulfur …
(a) Magnesium phosphate (b) Sulfur hexafluoride (c) Potassium carbonate (d) Sodium perchlorate (e) Magnesium hydroxide
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a. use the periodic table to write the formula (including the charge) f…
a. $Cl^{-}$ b. $Se^{2 - }$ c. $P^{3 - }$
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the element europium exists in nature as two isotopes: ^151eu has a mas…
The relative abundance of \(^{151}\text{Eu}\) is approximately \(48\%\) and the relative abundance of \(^{153}\text{Eu}\) is approximately \(52\%\).
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determine the most likely ion to form. a. will al gain or lose electron…
a. lose; $Al^{3 + }$ b. lose; $K^{+}$ c. gain; $As^{3 - }$
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question 13 of 24 > pure magnesium metal is often found as ribbons and …
6.03
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concept questions predict the product. predict the major organic produc…
1. A half - ester product from the reaction of the anhydride and 2 - propanol. 2. A diester product from the reaction of the di - acyl chloride and excess 3 - propanol. 3. An amid…
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polarity what does it mean by polarity? which end of the water attracts…
La polaridad es la separación de cargas eléctricas en una molécula. El lado del oxígeno en la molécula de agua actúa negativo y los lados de los átomos de hidrógeno actúan positiv…
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according to its nutrition label, orange soda contains 49 g of sugar pe…
$10.8\%$
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acetylene gas is not explosive. true false 24 of 25
B. False
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pre - laboratory assignment 2 name:______ section:______ date:______ be…
1. 3 2. $1.53\ g/mL$
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17 multiple choice 1 point here are 3 types of carbohydrates, what are …
D. A. Disaccharide B. Polysaccharide C. Monosaccharide
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10. the first battery electrified the world of science, increasing the …
10. Potassium 11. Sodium 12. attract
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examine the figure shown here and consider the following absorption lin…
Z, X, W, Y
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question 11 1 pts suppose you want to know the chemical composition of …
the wavelengths of spectral lines in the star's spectrum
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question 9 which of the following can be determined by examining the sp…
chemical composition, surface temperature
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question 14 of 24 balance the following combustion reaction in order to…
Yes, there is still $C_2H_4$ remaining.
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question 6 an atom that has fewer electrons than protons is called ____…
B. an ion
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question 13 of 24 if 70 moles of naoh combine with 27 moles of h₃po₄, h…
from $NaOH$: 70 moles $H_2O$ from $H_3PO_4$: 81 moles $H_2O$ limiting reagent: $NaOH$
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question 4 the chemical element of an atom is determined by the number …
C. protons
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the reaction between methanol and oxygen gas produces water vapor and c…
2
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condensation is a chemical reaction that releases hydrogen carbon dioxi…
C. water
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you burn a log on a fire. you use the fire to warm yourself and to ligh…
C. Chemical energy is transformed to light energy and thermal energy
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acetylene gas is not explosive. true false 5 of 5
False
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when water freezes, what type of change occurs? physical change nuclear…
A. Physical change
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question 5 (1 point) listen which of the following is an example of a c…
C. Baking bread
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when a physical change occurs, the composition of the substance changes…
False
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why does the temperature of ice remain constant at 0°c while it is melt…
Because the added heat is used to break the bonds between the ice molecules.
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question 1 provide the name of the catalyst for this reaction, if there…
phosphoric acid
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which of the following is an example of organic matter? a. sugar, which…
A. Sugar, which is made mostly of carbon, hydrogen, and oxygen
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read the excerpt from the author to her book. \thou ill - formd offspri…
D. A, A, C, C
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for each reaction, identify the substance that is the oxidizing agent a…
- For $C_2H_4 + H_2 ightarrow C_2H_6$: Oxidizing agent: $C_2H_4$, Reducing agent: $H_2$ - For $Fe_2O_3 + CO ightarrow 2FeO+CO_2$: Oxidizing agent: $Fe_2O_3$, Reducing agent: $CO$ …
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4. 15 g of four different solutes are added to four beakers, each conta…
A. Substance A, C. Substance C
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question 3 of 10 read this passage: kayla and emma are best friends, an…
D. Emma must decide whether or not to help Kayla cheat on the chemistry test.
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question 13 of 19 in some chemical reactions, electrons are transferred…
Oxidation of A: $A ightarrow A^{+}+e^{-}$; Reduction of X: $e^{-}+X ightarrow X^{-}$
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question 16 of 32 what is the main force that causes excess rainwater t…
C. Gravity
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question 11 of 32 carbonic acid forms when carbon dioxide dissolves in …
A. Chemical erosion
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question 9 of 32 which of these is a form of chemical weathering? a. th…
D. Oxidation
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what are shapes from nature called? (1 point) free - form or pure shape…
C. free - form or organic shapes
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1. which atomic window best represents a pure substance? 2. the air we …
1. d 2. c
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how does the structure of the water molecule help explain the ability o…
The polarity of water molecules and the resulting hydrogen - bonding among them cause water to form beads on non - polar wax surfaces as water molecules prefer to interact with ea…
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quiz: brain and addiction instructions: after reviewing facts on drugs:…
1. c) Chihuahua 2. b) releasing chemicals 3. a) limbic 4. a) becomes trained to crave the drug 5. b) needs more drug to get the same effect
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hobie draws the following model of a carbon atom. which change to the m…
A. Move each neutron so it is next to a proton.
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a scientist is studying two isotopes of sodium, labeled a and b. in iso…
A. 11 protons, 12 neutrons, and 10 electrons
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what event changes an atom into an ion? a. the sharing of electrons wit…
B. the gain or loss of one or more electrons
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water covers most of earths surface. the diagram shows the structure of…
Covalent bonds
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in a chemical reaction, which event always occurs as the reaction proce…
A. the rearrangement of electrons to break or form chemical bonds
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household bleach has a ph between 12 and 13. from this information, whi…
B. The solution is basic, meaning it has fewer hydrogen ($H^+$) ions than hydroxide ($OH^-$) ions.
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read the poem. excerpt from \paul reveres ride\ by henry wadsworth long…
It creates a proud and patriotic tone.
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what property of a water molecule allows hydrogen bonds to form among a…
None of the above options are correct. The correct property is the polarity of the water molecule.
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the elements sodium and chlorine react to form the chemical compound so…
A. very different
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which two types of particles are present in equal numbers in an atom, b…
A. protons and electrons
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9. explain how one of the earths natural processes is responsible for c…
9. Fossil fuels are created through sedimentation and decomposition of ancient organic matter over long time - scales. 10. Differences in geological, climatic, and tectonic proces…
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18 core electrons 8 valence electrons argon (ar): ne 3s²3p⁶ 10 core ele…
Core electrons: 10 Valence electrons: 2
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18 core electrons 1 valence electrons iron (fe): ar4s²3d⁶ core electron…
Iron (Fe): core electrons: 18 valence electrons: 8 Argon (Ar): core electrons: 10 valence electrons: 8
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the chemical formula for zinc nitrate is: zn(no3)2. calculate the molar…
189.4
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the chemical formula for diethyl sulfoxide is: (ch3ch2)2so. calculate t…
106.2 g/mol
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the chemical formula for calcium hydroxide is: ca(oh)2. calculate the m…
74.10 g/mol
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the chemical formula for acetone is: (ch3)2co. calculate the molar mass…
58.09 g/mol
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the chemical formula for octane is: ch₃(ch₂)₆ch₃. calculate the molar m…
114.3 g/mol
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read the passage from \to autumn.\ season of mists and mellow fruitfuln…
Rhyming "fruitfulness" and "bless" emphasizes the positive aspects of autumn.
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6. draw the lewis structures of 2 elements from each of the 4 families.
Let's assume four common families: alkali metals (Group 1), halogens (Group 17), noble gases (Group 18), and carbon - group elements (Group 14). - **Alkali metals (e.g., Li and Na…
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select all the mixtures. chocolate syrup ice cream cheese wet sand
Chocolate syrup, ice cream, cheese, wet sand
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select all the mixtures. soda water smoke cooking oil honey
soda water, smoke, cooking oil, honey
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select all the mixtures. sea water bread black pepper pudding
sea water, bread, black pepper, pudding
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select all the mixtures. butter nickel molasses carbon dioxide
butter, molasses
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select all the mixtures. pudding shampoo water vapor wet sand
Pudding, Shampoo, Wet sand
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select all the mixtures. cake batter caramel sauce milk salt water
Cake batter, Caramel sauce, Milk, Salt water
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select the two mixtures. cherry pie filling oxygen concrete sugar
cherry pie filling, concrete
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select all the mixtures. lava shampoo pizza dough carbon dioxide
lava, shampoo, pizza dough
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select all the mixtures. nickel water vapor smoke mercury
Smoke
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select all the mixtures. cracker carbon dioxide ketchup chocolate bar
cracker, ketchup, chocolate bar
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select all the mixtures. pizza dough water vapor honey nickel
pizza dough, honey
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select all the mixtures. cheese soda water bread chocolate bar
cheese, soda water, bread, chocolate bar
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organic foods to support farmers that do not use fertilizers on paper, …
C. By explaining how people can prevent pollution, he is offering a solution for readers.
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1. other than periods and groups how else is the periodic table divided…
| Family name (or section name) | 3 examples of elements in this family/section | # of e in last shell (if number changes put "varies") | Characteristics of this family/section | …
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a 0.2 mole of solid nh4cl is placed in one beaker and 0.1 mol of solid …
(a) Yes, both solids will dissolve when water is added to each beaker. (b) Double - displacement reaction occurs when the two chemicals come into contact with each other. (c) $Ag^…
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15. using the characteristics of the electron - configuration of elemen…
Br, P, Sr, Sc
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13. which of the following lists shows the elemental symbols ranked in …
D. Br, I, Cl, F
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12. which element has the ground state electronic configuration, 1s22s2…
potassium
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10. how would you draw a lewis dot diagram for the following atom of ar…
Draw the symbol 'As'. Place one dot each at the top, bottom, left, and right of the 'As' symbol, and then place the fifth dot on one of the four sides to pair with an existing dot.
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9 a core of and grouped together surrounded by which of the following b…
protons, neutrons, electrons