化学
化学反应、化学计量、分子结构与元素性质。
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what is the ability of a substance to be rolled or pounded into a thin …
A. Malleability
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what physical property is pictured? malleability conductivity solubilit…
Solubility
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what is the physical form in which a substance exists, such as solid, l…
B. State of Matter
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what are properties that can be observed without changing the make - up…
C. Physical Properties
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8. the water in the cup has a density of 1g/ml. mr. fauvell pours anoth…
$5\times10^{-3}\ L$
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a 5.40 x 10⁴ gram sample of iron at 290 k has a density of 7.874 g/cm³.…
1. 54000 grams 2. 54 kg 3. $16.85^{\circ}C$ 4. 1030 K 5. $6.86\times 10^{3}\ cm^{3}$
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a phospholipid molecule has two fatty acid molecules, one glycerol mole…
Only the statement "Unlike triglycerides, phospholipids have a phosphate group and two fatty acid chains." is true.
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question time! the change in enthalpy of a reaction is equal to the ent…
1. B. False 2. C. less than
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question time! when an ____ reaction occurs in an aqueous solution, hea…
1. A. exothermic 2. B. False
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match term with the correct equation. - change in enthalpy - change in …
- Change in enthalpy: $H_{products}-H_{reactants}$ - Change in temperature: Final temperature - Initial temperature - Heat gain or loss: (mass of solution) x (specific heat) x $\D…
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categorize each statement as representing an exothermic or endothermic …
Heat is absorbed from surroundings: Endothermic Heat is released to surroundings: Exothermic Temperature decreases: Endothermic Temperature increases: Exothermic The change in ent…
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states the total change in enthalpy is independent of the pathway the u…
1. Hess's Law 2. Joule 3. Endothermic 4. Thermochemistry 5. Exothermic 6. Enthalpy
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marine debris is best described as being composed of _. a. solid garbag…
D. things discarded by humans
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use the periodic table to select the element that best fits each of the…
# Explicación breve: Los iones de metales de transición a menudo dan color a las soluciones. El cloruro de níquel contiene iones de níquel, un metal de transición. Los elementos e…
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the electron configuration of nitrogen (n) is 1s²2s²2p³ 1s²2s²2p⁴ 1s²2s…
1s²2s²2p³ 对应的选项（假设为A选项）. 选项内容为1s²2s²2p³
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what is the number of valence electrons in cadmium (cd)? 1 2 10 12
2
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select the correct answer from each drop - down menu. the chemical form…
Coefficient: 4, Sub - script of carbon: 10, Sub - script of hydrogen: 8
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select the correct answer from each drop - down menu. hydrogen can be c…
solar energy
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stoichiometry - free - virtual - chemistry - lab - activity - stud... f…
1. Equation: $2B + C+M ightarrow1$ sandwich 2. Equation: $2B + C+M ightarrow1$ sandwich 3. There are 12 slices of bread left. Each loaf has 21 slices, so 2 loaves have $21\times2 …
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scientists who study elements and how they interact are called chemists…
The structure and properties of elements like oxygen and iron
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which element does the electron configuration 1s²2s²2p² represent? o b …
B. C
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what mass of sodium chloride will be required to completely react with …
388 g
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how many grams of sodium iodide are required to react completely with 3…
150. g
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how many moles of iron(iii) oxide are required to completely react with…
0.00775 mol
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what mass of sodium hydroxide will neutralize completely 3.612 mol of h…
144.5 g
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how many grams of water will be required to completely react with 1.00 …
18.0 g
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which image(s) would be considered pure substance(s)? *
3&5
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if a substance is made up of all one type of atom, it is______.* an ele…
A. An element
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nitrogen is a group 15 element. which statement about the other element…
They react in a way similar to how nitrogen reacts.
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by subtracting the atomic number from the atomic mass, i can find the n…
Neutrons
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jenny knows that the atomic number of the element potassium, k, is 19. …
B. 20
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if i know the atomic number, what subatomic particle do i also know? * …
B. proton
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during the marshmallow activity, 1 green and 1 pink marshmallow bonded …
A. Compound
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which of the following statements is true about mixtures and compounds?…
Mixtures can be separated into their components by physical means.
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answer the following. (a) a certain solution has a hydrogen - ion conce…
(a) $0.0000165$ (b) $4.7\times 10^{4}$
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misterf invented a test that analyses the chemical composition of coffe…
D. breaks down
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4. physical science the relationship between the numbers of oxygen atom…
| Oxygen atoms | 2 | 5 | 17 | 120 | | --- | --- | --- | --- | --- | | Hydrogen atoms | 4 | 10 | 34 | 240 |
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some support for this view is gained from study of the alchemistical wr…
A. documentation
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h₃c₆h₅o₇ in water: the final temperature of the solution was less than …
The reaction absorbed heat from the surroundings. The sign of $q_{reaction}$ is positive.
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the boiling point of a substance is the same temperature as... its free…
Its condensation point.
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consider this paragraph and select the sentence that best uses a subord…
a. While the storm raged outside, we stayed warm by the fireplace.
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in the equation 2h₂ + 1o₂ →→ 2h₂o if you change the 2h₂ to 3h₂ molecule…
It is not possible to produce water without leftover molecules.
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it takes 1 molecule of nitrogen and 3 molecules of hydrogen to produce …
$2N_2$ and $6H_2$
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balance of atoms quick check which statement correctly explains why the…
Some of the atoms in the paper became gases.
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the freezing point of a substance is the same temperature as... its mel…
A. its melting point.
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balance of atoms quick check one molecule of calcium oxide, cao, and on…
CaCO₃
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balance of atoms quick check when iron rusts and forms iron oxide, the …
Iron oxide has oxygen atoms, and pure iron does not.
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how can you best describe the behavior of the particles when a substanc…
The particles have a lot of energy and move around taking up as much space as possible.
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question 4 (3.57 points) across the world imperial lifestyle involved t…
- Question 4: exotic foods and banquets. - Question 5: True - Question 6: False
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name: partners name(s): period: 1) how many protons does an atom of alu…
1. 13 2. Cl 3. Molybdenum (Mo) 4. Se 5. Arsenic (As) 6. 15 7. Mg 8. Fe 9. 74 10. 25
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1. chapter 6: #6.28 2. chapter 8: #8.35 3. problem#3: based on satellit…
a) Sampling scheme: Stratified sampling. Reason: To represent different forest - types and get more precise estimates. b) Label parcels 01 - 42. Use Table B line 112, pick 4 uniqu…
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what is the correct lewis structure for ch4o
The first option (the structure $H-\underset{\underset{H}{\mid}}{C}-\ddot{O}-H$)
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how many unpaired electrons are in a p (phosphorus) dot structure: 4 1 …
D. 3
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question 17 (3 points) what is the correct ionic formula for magnesium …
Question 17: Mg Br₂ Question 18: 2
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what atoms listed below would form a covalent bond with each other? na …
C (carbon) and Cl (chlorine) It will become a cation
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question 13 (3 points) what is the electron arrangement for silicon (si…
Question 13: 2,8,4 Question 14: 24
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which formula correctly represents antimony trichloride? sns2 sncl3 sbc…
SbCl₃
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which element is a transition metal? lithium (li) argon (ar) strontium …
- Question 11: E. Rhenium (Re) - Question 12: A. 6
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which prefix would appear in the iupac name for a covalent compound tha…
C. tetra-
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which is the iupac name for no? o nitric oxide o binitrogen oxide o din…
nitrogen monoxide
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which of the following elements is a noble gas? iron (fe) bromine (br) …
Argon (Ar) It has mass but no charge.
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which is an iupac name for a covalent compound? carbon dioxide carbon b…
carbon dioxide
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which rule should be followed when naming binary acids? use a prefix fo…
Start the name with hydro-.
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which is the correct name for p₂o₅? phosphorus dioxide phosphorus pento…
C. diphosphorus pentoxide
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which is the name for so3? silver oxide trisulfur oxide sulfur trioxide…
sulfur trioxide
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which formula stands for boric acid? | name | symbol | | ---- | ---- | …
$H_3BO_3$
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which compound does h2so4 represent when in an aqueous solution? sulfur…
sulfuric acid
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which is the correct formula for phosphorus pentachloride? o pcl4 becau…
PCl₅ because a subscript of 5 indicates five Cl atoms
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question 18 of 20 which of these events is a likely result of chemical …
D. Algae are killed by solvents that have run off into a pond.
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question 10 of 20 the technology in the picture produces which energy c…
B. Kinetic energy to electrical energy
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the reaction of sodium(s) with water(l) to form sodium hydroxide(aq) an…
$-184.6\ kJ/mol$
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generate the heating graph for h₂o. determine the quantity of energy tr…
$104.5\ J$
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when the following equation is balanced properly under basic conditions…
The element reduced is Cl. Coefficient of $P$: 2 Coefficient of $Cl^-$: 6 Coefficient of $Cl_2$: 3 Coefficient of $PH_3$: 2 Water appears as a reactant with a coefficient of 6
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when the following skeletal equation is balanced under acidic condition…
Reducing agent: $Cd$ Coefficient of $Cd$: 1 Coefficient of $MnO_2$: 1 Coefficient of $Cd^{2+}$: 1 Coefficient of $Mn^{2+}$: 1 Coefficient of $H_2O$: 2
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balance the reaction between ph₃ and cl₂ to form p and cl⁻ in basic sol…
The coefficients of the species are: 2 for $\text{PH}_3$, 3 for $\text{Cl}_2$, 2 for $\text{P}$, 6 for $\text{Cl}^-$, 6 for $\text{OH}^-$ and 6 for $\text{H}_2\text{O}$. The numbe…
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which of the following increases the chance of cancer? i exposure to ce…
A. I, II, and IV only
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balance the reaction between so4 2 - and i - to form so3 2 - and i2 in …
Coefficient of $\text{SO}_{4}^{2 - }$: 1, Coefficient of $\text{I}^{-}$: 2, Coefficient of $\text{SO}_{3}^{2 - }$: 1, Coefficient of $\text{I}_{2}$: 1, Water coefficient: 1, Elect…
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tutor balance redox reactions in basic solution balance the reaction be…
$6Cl^- + 2H_2BO_3^- ightarrow 3Cl_2+2B$ Water appears in the balanced equation as a reactant with a coefficient of 8. The number of electrons transferred is 6.
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repetitions of syllables, i.e., the first sounds infants make that rese…
None of the above options are correct.
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a set of rules for combining the symbols, such as words, used in a give…
grammar
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check your mastery of 7.6 7.4 problem solving due october 12 the two ba…
A. grammar
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how many valence electrons are available for bonding in bromine (br)? o…
A. one
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which element has the greatest number of valence electrons available fo…
D. chlorine
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which characteristic best explains the difference in melting behavior o…
Covalent substances have weaker intermolecular attractions.
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which statement about covalent compounds is true? they are able to melt…
They are poor conductors of heat.
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some atoms are exceptions to the octet rule by having an expanded octet…
The atom has empty d - orbitals.
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what is the best reason for the difference in properties of licl and c6…
One compound is covalent, and the other is ionic.
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potassium permanganate reacts with oxalic acid (h2c2o4) & sulfuric acid…
A. 2,5,3,10,8,1,2
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4 multiple choice 25 points read the articles introduction paragraphs 1…
A. Both sections give specific examples of how matter can change.
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3 multiple choice 25 points how is the structure of the section “water …
Both sections present examples of how matter cycles through different phases.
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in a physical change, a substances physical properties may change, but …
D. same number
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question 29 1.66 pts titanium (ti) element compound mixture element com…
Element
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question 30 1.66 pts neon (ne) element compound mixture element compoun…
Element
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question 28 1.00 pts aluminum (al) element compound mixture © the scien…
A. Element
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question 27 1.66 pts vinegar (c₂h₄o₂) element compound mixture element …
Mixture
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take quiz exit ecm task cards started: oct 10 at 10:11am quiz instructi…
Mixture
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carbon (c) element compound mixture
Element
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question 23 1.00 pts hydrogen peroxide (h₂o₂) element compound mixture …
B. Compound
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potassium (k) element compound mixture element compound mixture
Element
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question 20 1.66 pts oxygen (o) element compound mixture element compou…
A. Element