化學
化學反應、化學計量、分子結構與元素性質。
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select the correct answer. both organic and functional mental disorders…
A. True
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question 2 1 pts which of the following statements best describes the s…
Electrons surround the nucleus.
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identify the period, block, and group in which the elements with the fo…
Period_3__ Block_p__ Group_7__
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identify the period, block, and group in which the elements with the fo…
Period__4__ Block__p__ Group__3__
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identify the period, block, and group in which the elements with the fo…
Period_7__ Block_p__ Group_8_ (although the correct group for np6 configuration is 18 in the modern periodic table, this is the best fit among the given options)
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clicker question if increasing the concentration of reactant a by a fac…
C. Second
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the percent composition by mass of a compound is 81.53 % c, 4.89 % h, a…
B. $C_{14}H_{10}N_{2}$
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7. what type of engineer would design new fuels, medicines, and textile…
(7) Chemical engineer (8) Civil engineer (9) a) Design (10) Optimize production - line efficiency (11) d) Engineering (12) b) Closed loop feedback
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1. fill in symbol and the number of valence electrons for the following…
1. Aluminum: Symbol - Al, Number of valence electrons - 3; Cl: Number of valence electrons - 7 2. c. 1, 2 3. b. [Ar]4s²3d³ 4. a. Copper 5. 1s²2s²2p⁶3s²3p⁴
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10. cooler water will__________, while warmer water will __________. 11…
10. Sink; Rise 11. Convection 12. Radiation 13. Waves 14. Conduct 15. Slowly
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what is the concentration of an aqueous solution containing 2.58 g of n…
1.89 M
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determine the percent composition of salicylic acid, c₇h₆o₃? the molar …
60.88% C, 4.379% H, 34.76% O
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what is the empirical formula of an unknown compound containing 63.13 %…
C. $C_{3}H_{5}O$
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if 6.32 ml of a 5.79 m solution of hydrochloric acid, hcl, is diluted t…
$0.183\ M$
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which word parts do you need to build a medical word that means inflamm…
1. C. -itis, phleb/o- 2. C. ischemia 3. C. septum
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7. even cold materials radiate some ___. 8. all molecules have ___. mor…
7. Infrared radiation 8. Kinetic; more 9. The ice sculpture
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directions: fill in the missing information for a given element. | | na…
1. Name: Oxygen, Total # electrons: 8, Electron Configuration (Full): $1s^{2}2s^{2}2p^{4}$ 2. Name: Chlorine, Total # electrons: 17, Electron Configuration (Noble Gas Notation): $…
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sulfur can be recovered from sour natural gas which contains 15 - 20% h…
| | \(H_2S\) | \(SO_2\) | \(S_8\) | \(H_2O\) | |---|---|---|---|---| | H | +1 | | | +1 | | S | -2 | +4 | 0 | | | O | | -2 | | -2 | Total number of electrons lost: 32 Total number …
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part b: each each scenario. decide whether a physical or chemical chang…
| Scenario | Physical or Chemical Change | Evidence | |--|--|--| | 1 | Physical change | No new substance formed, separation of plant part | | 2 | Chemical change | Fermentation a…
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a compounds percent composition is 40.0 % carbon, 6.71% hydrogen, and 5…
D. $C_{2}H_{4}O_{2}$
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question 10 (1 point) listen the ________ of a neuron contain ________ …
A. terminal buttons; synaptic vesicles
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how does the mass of a molecule affect the rate of diffusion? the light…
The lighter the molecule, the faster the rate of diffusion.
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what is the percent composition of aspirin, c₉h₈o₄? (molar mass of c₉h₈…
60.00 % C, 4.48 % H, 35.52 % O
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a compounds percent composition is 40.0% carbon, 6.71% hydrogen, and 53…
E. $C_{2}H_{4}O_{2}$
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what is the percent composition of aspirin, c₉h₈o₄? (molar mass of c₉h₈…
60.00 % C, 4.48 % H, 35.52 % O (corresponds to the second option in the multiple - choice list)
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if 0.850 l of a 5.00 m solution of copper(ii) nitrate, cu(no₃)₂, is dil…
$2.36\ M$
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if 0.850 l of a 5.00 m solution of copper(ii) nitrate, cu(no3)2, is dil…
$2.18\ M$
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nicotine contains 74.0 % carbon, 8.72 % hydrogen, and 17.3 % nitrogen. …
E. $C_{5}H_{7}N$
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nicotine contains 74.0% carbon, 8.72% hydrogen, and 17.3% nitrogen. wha…
C₅H₇N
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question 1 what is the percent by mass of aluminum in aluminum sulfate,…
15.77%
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what is the percent by mass of aluminum in aluminum sulfate, al₂(so₄)₃?…
15.77%
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39 the \two - hour rule\ of food storage applies to... a dry foods b pr…
D. perishable foods such as meat, poultry, fish, eggs, or dairy products
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20 household chemicals should be stored within easy reach under the sin…
A. False
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physical and chemical properties and changes name keyjaziyah phillips p…
**Properties**: 1. P 2. P 3. C 4. P 5. C 6. C 7. P 8. P 9. C 10. P 11. P 12. P 13. P 14. C **Changes**: 1. P 2. C 3. P 4. P 5. C 6. C 7. P 8. P 9. C 10. P 11. C 12. C 13. C 14. P …
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mixtures can be separated by physical means. what physical property is …
# Breve explicación: La filtración es un proceso de separación que utiliza un filtro con poros de un tamaño determinado. Las partículas más grandes no pueden pasar a través de los…
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mixtures can be separated by physical means. what physical property is …
# Breve explicación: La destilación es un proceso de separación que utiliza la diferencia en los puntos de ebullición de los componentes de una mezcla. Se calienta la mezcla hasta…
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a pure substance where all the atoms are identical. molecule element co…
# Breve explicación: Un elemento es una sustancia pura donde todos los átomos son idénticos. Un compuesto es formado por dos o más elementos diferentes combinados químicamente en …
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a mixture in which the substances have a uniform distribution. colloid …
# Breve explicación: En una mezcla homogénea, las sustancias están distribuidas uniformemente. Un coloide es una mezcla intermedia entre homogénea y heterogénea. Una mezcla hetero…
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a mixture in which the substances are not uniformly distributed. hetero…
# Breve explicación: En química, una mezcla heterogénea es aquella en la que las sustancias no están uniformemente distribuidas y se pueden distinguir a simple vista o con ayuda d…
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this type of homogeneous mixture is the best - mixed of all. it is made…
# Breve explicación: Las soluciones son mezclas homogéneas donde las partículas son átomos, moléculas o iones muy pequeños, invisibles a simple vista, que no se sedimentan y no pu…
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the part of a solution that gets the dissolved. usually, there is less …
# Breve explicación: En una solución, el soluto es la sustancia que se disuelve y por lo general está en menor cantidad por volumen que el solvente. El solvente es el que disuelve…
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question 12 5 pts which image above represents a pure element? c d e f …
# Explicación detallada: ## Paso 1: Comprender la naturaleza de un elemento puro Un elemento puro está formado por átomos idénticos. En las representaciones moleculares, se verán …
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question 13 1 pts which image above represents a pure compound? b d f e…
# Explicación breve: Un compuesto puro está formado por moléculas idénticas compuestas por dos o más tipos de átomos. La imagen C muestra solo moléculas compuestas por dos tipos d…
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which image above represents a mixture of atoms and molecules? a c d e …
# Explicación: ## Paso 1: Identificar átomos y moléculas Los átomos son partículas individuales (esferas solas), y las moléculas son átomos unidos entre sí (esferas unidas). ## Pa…
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the properties of a ____ do not vary because the composition is fixed. …
Question 15: pure substance Question 16: a substance has a fixed composition
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the smallest particle of an element is a compound a particle a molecule…
# Breve explicación: Un átomo es la partícula más pequeña de un elemento que conserva las propiedades químicas de ese elemento. Dos o más átomos unidos químicamente forman una mol…
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chemical formula so₂ electrons needed 8/2 for each atom electrons avail…
Electrons Needed: 24 Electrons Available: 18 Electrons Shared: 6 # of Bonds: 3 Electron Dot Diagram: Central S atom bonded to two O atoms (one double - bond and one single - bond)…
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study guide composition of matter one key term has been scrambled in ea…
1. A heterogeneous mixture has different materials that are spread out unevenly. 2. A colloid is a heterogeneous mixture whose particles never settle and are large enough to scatt…
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which of the following phase changes is exothermic? evaporation sublima…
# Explicaciones breves: - En un cambio de fase exotérmico, la sustancia libera calor al entorno. La evaporación, la sublimación y el hervor son cambios de fase endotérmicos donde …
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to move from a solid state to a liquid state, the average kinetic energ…
- Primera pregunta: D. increase - Segunda pregunta: C. decrease
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the change from solid to liquid is called ____ sublimation vaporization…
- La respuesta a la primera pregunta es: melting - La respuesta a la segunda pregunta es: condensation
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a book is pushed and released and it slides across a table for a short …
A. The kinetic energy is transformed into heat.
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what form of energy does a compressed spring have? a heat energy b kine…
D. potential energy
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question 1 - 11 when a substance such as salt is added to water, the sa…
polarity
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chemical formula ch4 electrons needed 8/2 for each atom electrons avail…
Electrons Needed: 16 Electrons Available: 8 Electrons Shared: 8 # of Bonds: 4 Electron Dot Diagram: Carbon in the center with 4 pairs of dots (electrons) connecting it to 4 hydrog…
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part a according to the law of conservation of energy, energy is not cr…
D. chemical energy → electrical energy → heat and light energy
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tech a says that pushing on the brake pedal stops the vehicle by conver…
B. Tech B
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chemical formula co electrons needed 8/2 for each atom electrons availa…
Electrons Needed: 16 Electrons Available: 10 Electrons Shared: 6 # of Bonds: 3 Electron Dot Diagram: A triple bond between C and O with two lone - pairs on O and one lone - pair o…
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chemical formula o3 electrons needed 8/2 for each atom electrons availa…
Electrons Needed: 24 Electrons Available: 18 Electrons Shared: 6 # of Bonds: 3 Electron Dot Diagram: One oxygen atom double - bonded to a central oxygen atom and single - bonded t…
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chemical formula co2 electrons needed 8/2 for each atom electrons avail…
Electrons Needed: 24 Electrons Available: 16 Electrons Shared: 8 # of Bonds: 4 Electron Dot Diagram: $\ddot{O}=C=\ddot{O}$
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when adding a powder to a liquid, the powder disappears (hint: the powd…
physical change (no reaction)
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when mixing two clear liquids, it becomes very cloudy (hint: a new subs…
# Explicación: ## Paso 1: Identificar el fenómeno Se forma una nueva sustancia sólida en agua al mezclar dos líquidos claros. Esto indica una reacción química. ## Paso 2: Definir …
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when you mix two room - temperature liquids, and it gets warm (hint: it…
# Explicación breve: La mezcla de dos líquidos a temperatura ambiente que se calienta debido a la liberación de energía cuando se forman nuevas sustancias es un ejemplo de cambio …
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pre - lab quiz - exp 7a - calorimetry score: 0/10 answered: 0/5 questio…
$6.01\ kJ/mol$
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when you heat water and it boils (hint: h₂o liquid becomes h₂o gas) you…
physical change (no reaction)
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which of these are examples of physical changes? a: melting/freezing, b…
D. all of these
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use the periodic table to fill in the table with the number of protons …
| Elements | # of Protons | |--|--| | Hydrogen | 1 | | Helium | 2 | | Sodium | 11 | | Calcium | 20 | | Mercury | 80 | 1. Heavier 2. Light 3. Heavy
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which macromolecule makes up most of a marshmallow? what atoms are foun…
- ¿Cuál macromolécula constituye la mayor parte de un malvavisco? Carbohidratos. - ¿Qué átomos se encuentran en esta macromolécula? Carbono (C), Hidrógeno (H) y Oxígeno (O). - ¿Qu…
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10. what is the difference between hand antiseptic and hand soap? why i…
10. Hand antiseptics use chemicals to kill microbes, hand - soap physically removes dirt and microbes. Hand - soap is more important for broader removal. 11. Bathrooms, kitchens, …
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question 8 of 12 sci_phys_cfa2_propertiesofma... submit test which stat…
Both substances are equally soluble at 30°C.
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a marketing team reviews survey results from an organic personal care p…
B. Ease of use
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question 4 of 12 sci_phys_cfa2_propertiesofma... submit test mass 10 0 …
Both substances are equally soluble at 30°C.
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a. the atomic mass is calculated by adding the masses of protons to neu…
25. B. 43 protons, 56 neutrons, and 43 electrons 26. B. air 27. B. 11.57 weeks 28. A. 63360 inches 29. Compounds and elements are pure substances; heterogeneous and homogenous are…
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20. although a meteorite might travel millions of kilometers to reach e…
20. A. Iron is a pure substance. 21. C. Atoms can be subdivided into smaller subatomic particles; protons, neutrons, and electrons exist in an atom. 22. A. Atoms consist of a posi…
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16. which of the following is a physical property? a. the flammability …
C. 2g
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c. thomson set up the gold foil experiment. most of the alpha particles…
C. 3 amu ### 13.
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10. ann created the following diagram to help her understand a chemical…
10. A. A - atom, B - molecule, C - compound 11. None of the given options are completely correct. Thomson used a cathode - ray tube, the deflection of the cathode rays (not alpha …
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evolution of the atomic model which of the following is the best explan…
1. A. Advancements in technology enabled scientists to infer more details about atomic structure. 2. B. Observation #2 3. D. The solid bubbled when placed in acid.
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solubility of ionic compounds classify each of the compounds as soluble…
copper(II) chloride: soluble nickel(II) sulfide: not soluble calcium iodide: soluble
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6. match up what you think each of these symbols mean: 1. e 1s² 2s² 2p⁴…
1. E) a sublevel (orbitals with equal energy) 2. B) a single orbital (place where electrons are likely found) 3. B) a single orbital (place where electrons are likely found) 4. C)…
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similar to the previous picture, here is how will fill the electrons in…
1. E 2. B 3. E 4. C 5. D
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in classical conditioning, ______ occurs when the conditioned stimulus …
Question 1: B. extinction Question 2: E. explicit
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which multimedia element would most appeal to an audiences emotions in …
a photo of a dried - up lake and a photo of a family swimming in the lake before it dried up
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1. fe(s) + s(s) → fes(s) is this experiment a physical or chemical chan…
1. Chemical change 2. A new substance (iron - sulfide) is formed with different color and chemical properties. 3. Heat was applied to provide activation energy for the reaction. 4…
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part b: true/false write t for true or f for false. 1. gases are allowe…
1. False 2. False 3. True 4. True 5. True 6. False 7. True 8. False 19. c) Used to measure temperature 20. d) Used as a heating apparatus 21. a) Used for holding small samples of …
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2022 chemistry q1 exam 1. a student fills a 100 ml graduated cylinder w…
1. D. 33.0 mL 2. D. Isabella obtained the better accuracy and precision. 3. D. 141 ounces
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instructional science long test (term 1) kankakee high school 6. salt m…
6. b) Mixture 7. c) Burning wood 8. b) Mass and volume 9. b) Pipette 10. a) Phase
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part a: multiple choice, choose the letter of the correct answer. encir…
1. a) Beaker 2. a) Bunsen burner 3. b) Goggles 4. b) Physical change 5. b) Liquid
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25 review questions 1. what is an atom? 2. define an element. 3. what a…
1. An atom is the basic unit of matter, consisting of a nucleus and electrons. 2. An element is a pure substance with one - type of atom. 3. Subatomic particles are particles smal…
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chapter 2 properties of matter compounds (page 40) 10. what is a compou…
10. A substance formed by the chemical combination of two or more elements in a fixed proportion. 11. a. A compound always contains at least two elements. b. The substances that m…
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chapter 2 properties of matter section 2.1 classifying matter (pages 38…
1. True 2. a. Element b. Compound 3. A substance that cannot be broken down into simpler substances by chemical means. 4. True 5. Because it consists of only one type of atom. 6. …
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6. define chromatography and distillation. give an example of where eac…
### 27. Mass is the amount of matter in an object, a scalar quantity. Weight is the force exerted on an object due to gravity, a vector quantity. You get mass directly from a bala…
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classification of matter check the appropriate categories for the subst…
| Substance | Heterogeneous Matter | Homogeneous Matter | Pure Substance | Solution | Element | Compound | Mixture | |---|---|---|---|---|---|---|---| | Lead | | √ | √ | | √ | | |…
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5. are there any separated pigment colors common to your different star…
1. To prevent filter - paper disintegration and ink - mixing. 2. Due to differences in particle size, solubility, and polarity. 3. Because their inks dissolve in water for chromat…
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classification of matter worksheet homogeneous vs. heterogeneous matter…
1. Heterogeneous 2. Heterogeneous 3. Heterogeneous 4. Homogeneous 5. Heterogeneous 6. Homogeneous 7. Homogeneous 8. Homogeneous 9. Heterogeneous 10. Homogeneous 11. Homogeneous 12…
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what did upton sinclairs the jungle reveal to many americans, and what …
1. How dangerous and dirty meatpacking was. The public outcry helped lead to the Pure Food and Drug Act and the Meat Inspection Act 2. Public laws in which city officials took res…
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which statement is true? a the relative mass of an electron is negligib…
A. The relative mass of an electron is negligible
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a covalent bond is denoted by ______ in a lewis dot structure: two dots…
B. a straight line
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a covalent bond can occur between two atoms of the same element. true f…
True
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what type of chemical bond is found in nitrogen dioxide? ionic lewis co…
C. covalent