化学
化学反応、化学量論、分子構造、元素の性質。
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what causes pressure inside an inflated soccer ball? a. the gas molecul…
C. The gas molecules move rapidly and collide with the surface of the ball.
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question 8 of 30 how can a mixture of salt and sand be separated? a. by…
C. By dissolving the salt in water and filtering out the sand
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question 8 of 10 a solution was prepared by adding 641 mg of sodium chl…
\(25.7\) (Wait, no, earlier calculation was 25.7282, and if we consider significant figures in the sum, maybe I made a mistake. Wait, 641 mg is 0.641 g (three sig figs), 72.2 mg i…
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the mass of a beaker was measured to be 125.445 g. a buret was used to …
\( 0.372 \)
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question 8 5 points using your data table 1, from your procedure docume…
4
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question 7 of 30 what is the pressure of 0.5 mol nitrogen (n₂) gas in a…
C. 1.7 atm
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question 6 using your data table 1, from your procedure document: input…
3
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question 6 of 30 a mixture of he, ne, and n₂ gases has a pressure of 1.…
A. 1.24 atm
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question 5 of 30 which substance will form a solution when mixed with s…
D. $\ce{CH_{3}OH}(l)$
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3. condensation is an exothermic process. this means that energy ______…
has been removed from a system
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question 6 of 10 perform the following calculations and report your ans…
First calculation: $\boxed{8.6}$ (wait, but earlier I thought 8.5557 rounded to two sig figs is 8.6? Wait, 8.5557: first two sig figs are 8 and 5. The next digit is 5, so we round…
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the cylinder shown at right, the correct volume is 56.0ml. data table e…
s for Part 2: a) $\boldsymbol{1547}$ (or $1.547\times 10^{3}$) milliliters b) $\boldsymbol{20.}$ (or $2.0\times 10^{1}$) inches c) $\boldsymbol{7666}$ (or $7.666\times 10^{3}$) gr…
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question 5 of 10 report the following values to the specified number of…
$0.00100$ ### 98289 reported to 2 significant figures:
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question 4 of 10 three groups of students were tasked with determining …
s: - Most accurate: Group 1 - Most precise: Group 2 (For the multiple-choice format: Which group was most accurate? \(\boldsymbol{\text{Group 1}}\) Which group was most precise? \…
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1. thermal energy is added to water. which of the following describes t…
Bonds have been broken that hold particles in place.
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if you wanted to measure the volume of a liquid to the greatest precisi…
D. buret (Note: Assuming the options are labeled as A: All of the glassware... , B: graduated cylinder, C: Erlenmeyer flask, D: buret, E: beaker. If the original labeling is diffe…
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classify the glassware used in this experiment based on the number of d…
- 0 decimal places: beaker, Erlenmeyer flask - 1 decimal place: graduated cylinder - 2 decimal places: buret - 3 decimal places: (No glassware from the answer bank)
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12. how are the codes (chemical formulas) for 13. use what you have jus…
To solve this, we recall the definitions: - **Element**: Consists of only one type of atom (chemical symbol of one element). - **Compound**: Consists of two or more different elem…
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7. appoint one group member to cut apart model 1 to separate the nine d…
To solve these questions, we analyze the definitions and apply them: ### Question 8 #### Brief Explanations: - **Pure Substances**: Drawings where all particles are identical (mat…
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steel is an example of a pure substance because it is made up of two di…
false ### Question 6 (Salt dissolving in water):
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question 4 (multiple choice worth 4 points) (01.06br mc) which of the f…
The particles have no set ratio for how to combine, and they can be separated by physical means.
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what type of solution contains more solute than would normally dissolve…
Supersaturated (the option corresponding to "Supersaturated")
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during an experiment, iron powder and sulfur powder were mixed thorough…
Iron powder and sulfur powder combined physically, therefore they retained their individual properties.
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part 2: what is whmis? workplace hazardous materials information system…
To solve this WHMIS (Workplace Hazardous Materials Information System) symbol - matching problem, we analyze each symbol, its name, and the safety implications: ### Symbol 1 (Expl…
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check for understanding use your understanding of density to complete t…
B. vegetable oil, 0.71 g/mL ### Part 2: Identifying Substances by Density (Sample A, B, C) #### Sample A: 225 grams, 50 milliliters
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check for understanding use your understanding of density to complete t…
B. vegetable oil, 0.71 g/mL ### Part 2: Identifying the metal samples #### 1. Sample A: 225 grams, 50 milliliters
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chapter 20: chemistry 11.8.1 high resistance to... the area is called a…
Assuming the options are related to chemistry lab liquid expulsion under pressure, and if we correct the OCR - garbled options, the correct answer would be the option related to f…
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exercise b suppose you are writing a report about cancer research and c…
The article is credible. It cites a credentialed researcher (Dr. Folkman), reports experimental results, and includes cautionary notes about human application, showing balanced an…
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3. fill in the following chart. don’t forget to come the isotope symbol…
To solve this, we use the following relationships: - Atomic number (\(Z\)) = number of protons (\(p^+\)) - Mass number (\(A\)) = number of protons (\(p^+\)) + number of neutrons (…
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lesson 37 continued 2. a brochure about home security systems, publishe…
The article has reasonable credibility. Dr. Folkman’s credentials (research scientist at a medical research center) give expertise. The major newspaper has basic fact - checking s…
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3. use the graph paper on the back of this page to plot the data in the…
Approximately 0.94 g/mL (or more precise 0.938 - 0.94 g/mL) ### Part b:
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look at the picture. then, choose the best answers. 2. choose the best …
intensive ### Question 3
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periodic table assignment magnesium is in group □ and period □. gallium…
Magnesium: group 2, period 3; Gallium: group 13, period 4
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19. choose the best answer. who reasoned that it is impossible for all …
B. Democritus
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who proposed the law of definite proportions? ○ crookes ○ thomson ○ pro…
C. Proust ### Second Question (Who discovered the nucleus?):
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16. choose the best answer. how many valence electrons does iodine have…
7 (corresponding to the option with 7)
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15. choose the best answer. who proposed that matter could only be divi…
A. Democritus
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jill mixes two types of concentrations of hcl (hydrochloric acid): 0.37…
50% (Option: 50%)
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physical science study guide – chapter 4 name: be sure to study these q…
a) Kinetic ### Question 2
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ws: ideal gas and more answer the following showing your work and prope…
7.69 L
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3. true or false: analytical chemistry focuses on identifying the compo…
True
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atomic model proposed by j. j. thomson model shows negative electrons f…
The atomic model proposed by J.J. Thomson is the one with the description "model shows negative electrons floating in a'soup' of positively charged material" (corresponding to the…
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2. which branch studies energy and reaction rates? a) biochemistry b) p…
b) Physical Chemistry
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13. match the statements with the pictures. answers can be used more th…
### Matching the Atomic Models: #### 1. Atomic model proposed by Dalton (A) - Dalton's model (A) is a solid sphere, representing the idea that atoms are indivisible and indestruct…
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1. match the branch of chemistry with the correct example: branch examp…
Organic Chemistry: B. Plastics and fuels Inorganic Chemistry: C. Iron and table salt Biochemistry: A. DNA and proteins
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the number of protons in an atom determines an atom’s identity and affe…
Top (lowest protons): neon Next: magnesium Next: silver Bottom (highest protons): plutonium (Order: neon, magnesium, silver, plutonium)
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how many electrons are found in each energy level of a neutral atom of …
- third energy level: three electrons - first energy level: two electrons - second energy level: eight electrons
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an atom of iron has an atomic number of 26 and a mass number of 56. how…
26 protons, 30 neutrons, 26 electrons (corresponding to the third option among the given choices) ### Second Question (Atomic Number and Neutrons Statement)
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14. an agency of the usa department of labor whose function is to regul…
Occupational Safety and Health Administration (OSHA) ### Question 15
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periodic table of the elements get help here an atom that has four prot…
An atom that has three protons.
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identify some of the important similarities and differences between the…
To solve this, we analyze each description and match it with protons, neutrons, or electrons: ### 1. Determines the atomic number The atomic number is equal to the number of proto…
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question 4 of 30 the graph below shows how the pressure and volume of a…
D. The pressure decreases.
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26 the letters ph denote _________________, which is the relative degre…
potential of hydrogen (or power of hydrogen); acidity; alkalinity ### Question 27
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which of the following is a heterogeneous mixture? a. gold alloy b. rub…
D. Paint
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6. susceptible host | an individual who is at an \increased risk\ for i…
To solve these fill - in - the - blank questions related to medical and health concepts, we analyze each one: ### Question 8 - **Explanation**: When a pathogen is transmitted from…
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question 1 of 30 what is the volume of 0.24 mol oxygen (o₂) gas at 345 …
D. 9.1 L
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molecules are ○ three or more atoms held together by chemical bonds ○ t…
two or more atoms held together by chemical bonds ### Second Question (Electrons have a ____ charge):
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14. an agency of the usa department of labor whose function is to regul…
Occupational Safety and Health Administration (OSHA) ### Question 15
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life depends on this important element ○ carbon ○ boron ○ lithium ○ oxy…
A. Carbon ### Second Question: "Compounds are"
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25 match the following examples with the correct answer. choices may be…
To solve this, we analyze each substance based on the definitions of solution, suspension, and emulsion: - **Witch hazel**: A homogeneous mixture (solute dissolved in solvent), so…
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8. pathogen is transmitted from contaminated surfaces such as food or e…
Fomite transmission ### Question 9
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question 4 / 4 which number does not have three significant figures? a.…
D. 700 mL
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match the descriptions below to either metal or nonmetal. good conducto…
- Good conductors of heat and electricity: metals - Found on the left side of the Periodic Table: metals - Solids are usually brittle: nonmetals - Malleable and lustrous: metals -…
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how many significant figures are in 0.0320 g? a. one b. two c. three d.…
C. Three
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which element will demonstrate similar reactivity that sulfur has? ○ ch…
Oxygen
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question 3 / 4 how many significant figures are in 0.0320 g? a. one b. …
C. Three
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metals are located on the blank of the periodic table, and nonmetals ar…
Metals are located on the left side of the periodic table, and nonmetals are located on the right side. Metalloids are located on the zigzag line of the periodic table.
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the first \periodic table\ was created by △ who arranged the elements b…
First "periodic table": Created by John Newlands, arranged by atomic mass (law of octaves). Current periodic table: Created by Dmitri Mendeleev (foundation) / Henry Moseley (moder…
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what is the atomic number of the next element in the same period as pho…
16 (corresponding to the option "16")
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periodic table assignment which letter represents periods on the period…
1. A 2. B
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in period 3, there are 8 elements. what sublevel(s)/orbitals is(are) be…
s, p
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the horizontal rows on a periodic table have the same question #elsic |…
number of energy levels/ rings
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what is the atomic number of the next element in the same group as bery…
D. 12 (assuming the last option is 12, as per the context of Group 2 elements; Beryllium is in Group 2, next element is Magnesium with atomic number 12)
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in period 5, there are 18 elements. what sublevel(s)/orbitals is(are) b…
A. s, B. p, C. d
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the number of valence electrons in group 13 is ______. ○ 13 ○ 3 ○ 5 ○ t…
B. 3 (assuming the options are labeled as A. 13, B. 3, C. 5, D. the same as it’s period number)
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all ____ formed ____ two more ____ molecule ____ solvent: water ____ al…
1. All \(\boldsymbol{\text{compounds}}\) (or \(\boldsymbol{\text{substances}}\)) formed \(\boldsymbol{\text{by}}\) two or more \(\boldsymbol{\text{atoms}}\) of a \(\boldsymbol{\te…
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question 5 (essay worth 4 points) which of the following is an example …
Rusting iron
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when heat energy is added, two changes are observed: change a: solid ch…
A is melting and B is sublimation. (The option corresponding to "A is melting and B is sublimation" among the given choices)
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air ______ bone formed ______ two or more ______ molecule ______ solven…
1. For the "molecule formation" part: A molecule is formed when two or more atoms bond. For water, a water molecule ($H_2O$) is formed from two hydrogen atoms and one oxygen atom.…
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which of the following is a sign a chemical reaction has occurred? a so…
A solid forms when two liquids are mixed.
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20. which most accurately describes the structure of an atom? image of …
B. Protons and Neutrons are in the nucleus. Electrons surround it. (Note: Assuming the second option is labeled as B; adjust the label based on the actual question's numbering if …
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question 1 (multiple choice worth 4 points) (01.05r mc) rubbing alcohol…
The gas particles move faster, have the same molecular composition, and have weaker attractions between them than the liquid particles.
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20 match the following attributes with the correct answer. choices may …
To solve this matching problem, we analyze each attribute based on the definitions of pure substances, physical mixtures, and chemical compounds: ### 1. "created through a reactio…
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question 1-8 you are testing how well different dish soaps clean grease…
Type of dish soap used
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a student records the following data during a wetland visit: \the water…
The statement about a chemical spill is an inference because it attempts to explain the cause of the observations ### Second Sub - Question (Independent Variable)
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physical and chemical properties worksheet circle the choice that best …
both ### Question 2
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8. into the bushes fled the frightened rabbit. 9. to stay strong, i pra…
Subject: \underline{your sister}; Verbs: \underline{\underline{did}}, \underline{\underline{go}} ### 2. Sentence: All of the packages were delivered.
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15 ____________________ refers to either the loss of oxygen or the addi…
Reduction ### Question 16
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describing the amount of product in a chemical equation marcia is given…
Marcia can use the law of conservation of mass (conservation of atoms). This law states that the number of atoms of each element in reactants equals that in products. Since the pr…
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why does ice float when it is placed in liquid water? because the densi…
because the density of ice is less than water
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identify each part of this chemical equation, which describes the break…
A (the entire green box): Chemical Equation B (the blue box): Reactant C (the arrow): Reaction Arrow (Yield Sign) D (the purple box): Products
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3. a student is writing an essay about the health benefits of organic p…
B. www.pacificuniversity.edu/organic: a website that provides recent research studies conducted on the impact of organic produce on the human body
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a student is performing a chemical reaction. the mass of reactant 1 is …
64 grams (corresponding to the option "64 grams")
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which of the following is a bond defined by the sharing of electrons be…
A. Covalent Bond
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the number 3 in 3o₂ indicates that there are (1 point) 3 subscripts thr…
Three molecules of \( O_2 \) (diatomic Oxygen)
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the gaseous state of matter is found between the solid and liquid state…
b. FALSE
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name: ____________ teacher: ____________ q1 chemistry: u1l6 mixture sep…
Left technique: Filtration. Separates sand and salt (after dissolving in water: filter sand, evaporate salt from filtrate). Right technique: Distillation. Separates salt and water…
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suppose you have three identical test tubes that contain equal masses o…
b. Gas: It expands to fill the container.
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which of the following best describe gas particles? select all that app…
a. moving randomly, b. collide into each other, d. high kinetic energy
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physical properties are characteristics that can be observed without ch…
The color of the pufferfish's scales