化學
化學反應、化學計量、分子結構與元素性質。
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use what you know about the periodic table, atomic number, and atomic m…
| Element Name | Atomic Symbol | Atomic Number | # of electrons | # of Protons | # of neutrons | | ---- | ---- | ---- | ---- | ---- | ---- | | Lithium | Li | 3 | 3 | 3 | 4 | | Hel…
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an atom of the element chromium has an atomic number of 24 and a mass n…
B. 24
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30. what do elements of the same group in the periodic table have in co…
30. They have the same number of valence electrons and similar chemical properties. 31. Elements close to each other have more similar properties than those far apart. 32. Look fo…
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11. classify each of the following as a physical or chemical change. a.…
a. Physical b. Chemical c. Chemical d. Physical e. Physical f. Chemical
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jose needs 6.2 lb of organic blueberries to make smoothies. organic blu…
Jose incorrectly rounded $2.85$ down to $2$. The estimate should be $18$.
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which statement describes one feature of a minerals definite chemical c…
It always contains certain elements.
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atoms, elements, compounds & mixtures task 1: rewrite the sentences if …
# Explicación detallada: ## Paso 1: Corregir enunciados erróneos 1. El enunciado "All matter is made of tiny particles called elements" es incorrecto. La materia está hecha de par…
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the pictures show two different models of the atom. type in the letter …
The model that best represents Dalton's atomic theory is B. The model that best represents the modifications due to Thomson's results is A.
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14. describe the contents of each cell using the terms (where applicabl…
### 14. - **Cell A**: - # Explanation: ## Step1: Analyze particle - arrangement The particles are closely packed in a regular pattern and there are different types of atoms bonded…
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6. which of the following is a chemical change? a) ice melting b) water…
6. d) Gasoline burning 7. d) Definite shape and volume, tightly packed particles 8. c) A state of matter that has no definite shape but has a definite volume. Takes the shape of i…
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name: dyllan date: period: 1. which of the following is the best defini…
1. b) Anything that takes up space and has mass 2. c) Sound 3. c) Melting point 4. d) Ability to burn 5. b) Dissolving sugar in water
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elements in the same group have the same number of __ in their outer sh…
Electrones
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check the box under each molecule in the table below that is an isomer …
Check the box under the third molecule (hex - 2 - ene) and the fourth molecule (3 - methyl - pent - 2 - ene)
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what is the rhyme scheme of the first stanza of frosts \the road not ta…
C. ABAAB
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what atoms are in a compound with the formula nbr3? a. 1 nitrogen atom …
A. 1 nitrogen atom and 3 bromine atoms
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carbohydrate lab questions 1. what indicator do we use to test for a ca…
1. La solución de Benedicto. 2. Azul. 3. Naranja - roja. 4. No se puede determinar con la información dada. 5. Almidón. 6. Púrpura - negro (sólido puro), marrón - ámbar (en disolu…
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name these organic compounds:
1. Propanal 2. 1 - Propanol 3. Ethanoic acid
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how are reactivity and electronegativity related? (1 point) elements wi…
An element will be more reactive if it has a very high or very low electronegativity.
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which elements on the periodic table are the least reactive? (1 point) …
the group with helium at the top
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name the family to which each organic compound belongs. the first answe…
1. Amide 2. Ether 3. $\alpha,\beta$-unsaturated carbonyl compound
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which element would have the lowest electronegativity? (1 point) o an e…
an element with a small number of valence electrons and a large atomic radius
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atoms and their parts (subatomic particles) substances that contain onl…
1. 1 2. 0 3. 1 4. 1 5. 1
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name the family to which each organic compound belongs. the first answe…
1. Amide 2. Ether 3. Diketone
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name the family to which each organic compound belongs. the first answe…
1. aldehyde 2. amide 3. alcohol
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homework review atoms, elements, compounds & mixtures learning objectiv…
# Breve explicación: Los átomos son los bloques de construcción básicos de la materia. Los elementos están formados por un solo tipo de átomo y no se pueden descomponer en algo má…
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3 tries left what distinguishes a form from a shape? a form refers to s…
D. A form appears to be three - dimensional.
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what is the term for the energy required to initiate a chemical reactio…
activation energy
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which of the following statements explains why marshmallows and other s…
low activation energy
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matching match the correct description with the correct term. write the…
13. f. solubility 14. j. density 15. e. state of matter 16. b. composition 17. h. electrolysis 18. c. nonflammability 19. d. inertia 20. a. thermal conductivity
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if a test sample burns fully in a calorimetry experiment, what has it r…
complete degradation
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3 tries left the most common man - made shapes are organic. geometric. …
B. geometric.
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answer the questions in the table about each labeled atom in the molecu…
| Atom | Electron Group Geometry | Hybridization | | ---- | ---- | ---- | | Atom a | Trigonal planar | $sp^{2}$ | | Atom b | Trigonal planar | $sp^{2}$ | | Atom c | Trigonal plana…
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what does the law of entropy state? disorder increases with every energ…
Disorder increases with every energy transfer.
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what is the best definition of strategy? (1 point) a means for measurin…
B. a plan for achieving something
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7. what chemical property is responsible for iron rusting? a. flammabil…
7. d. reactivity with oxygen 8. c. more mass than the 50 g ball has. 9. b. g/cm³ 10. a. density 11. d. chemical change. 12. a. physical property.
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question 9. select the correct word that would complete the sentence to…
First blank: physical Second blank: chemical
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question 20 which of the following has one example of a physical change…
C. boiling water and melting wax, rusting iron and baking a cake
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waves webquest part 2 use this diagram to answer a - d. a. what type of…
a. Transverse wave b. i. U: Crest, ii. R: Rest position, iii. D: Trough c. (Horizontal line between two consecutive crests labeled W) d. (Vertical line from R to U labeled A) e. L…
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the chart below shows the density of five gases. density of gases gas d…
A. Argon
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question 17 which of the following is a chemical change? o ice melting …
water breaking down into hydrogen and oxygen
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instructions: for each test item, identify the choice that best complet…
C. a gas is formed when vinegar and baking soda are mixed
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instructions: for each test item, identify the choice that best complet…
melting
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unit 2 - electrons and periodic table test part 1 - multiple choice: se…
1. B. Carbon 2. B. 3, 7 3. B. Boron 4. D. 8 5. C. Magnesium 6. D. Both A and B 7. A. Group 17 8. D. Fr 9. D. Ba 10. B. high; negative 11. B. S 12. C. \(1s^{2}2s^{2}2p^{6}3s^{1}\) …
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a modernist poem that deliberately breaks traditional rhyme schemes and…
Experimentation with format
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name the functional group shown in each molecule below. the first answe…
1. Amide 2. Ether 3. Carboxylic acid
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chapter test a the properties of matter multiple choice write the lette…
1. d. weight 2. a. floating at the top 3. c. The composition is unchanged in a physical change. 4. b. physical change 5. c. liters or milliliters 6. b. change in state
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when sugar is mixed with water, equilibrium is reached when multiple ch…
the dissolved sugar molecules are evenly distributed throughout the solution
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instructions: for each test item, identify the choice that best complet…
compounds
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unit 2 - electrons and periodic table test part 1 - multiple choice: se…
1. B. Carbon 2. B. 3, 7 3. B. Boron 4. D. 8 5. C. Magnesium 6. D. Both A and B 7. A. Group 17 8. D. Fr 9. D. Ba 10. B. high; negative 11. B. S 12. C. $1s^{2}2s^{2}2p^{6}3s^{1}$ 13…
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started sep 4 at 1:07pm quiz instructions instructions: for each test i…
homogeneous
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3b. determine whether the situation below is showing a chemical change …
Chemical Change
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question 11 3 pts which classification would best describe a material w…
C. colloid
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learning target i can identify whether a change is physical or chemical…
Physical Change
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instructions: for each test item, identify the choice that best complet…
the size of its particles
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unit 2: electrons and periodic table test part 1: multiple choice - sel…
7. No answer provided for this part in the question - setup. 8. D. Fr 9. B. Ba 10. B. high; negative 11. D. Si 12. C. \(1s^{2}2s^{2}2p^{6}3s^{1}\) 13. B. 3 14. C. Ar
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the term route of entry on an sds refers to the way a ____ enters the b…
D. Chemical
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instructions: for each test item, identify the choice that best complet…
D. suspension
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instructions: for each test item, identify the choice that best complet…
the size of its particles
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unit 1 test: matter (2025) started: sep 4 at 1:07pm quiz instructions i…
brass
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a student sets up the following equation to convert a measurement. (the…
$\frac{1\ kJ}{10^{3}\ J}$
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instructions: for each test item, identify the choice that best complet…
has varying properties
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if a material contains three elements joined in a fixed proportion, it …
C. compound
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classify each of the following as either a physical change or a chemica…
1. Physical change 2. Chemical change 3. Physical change 4. Physical change 5. Chemical change 6. Chemical change
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unit 1 test: matter (2025) quiz instructions started sep 4 at 1:07pm in…
Gold
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question 2 3 pts a substance that is made up of only one type of atom i…
B. element
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here is the chemical structure of 1 - chloro - 2 - methylpropane: decid…
1. Isomer 2. Isomer 3. Different compound
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2b. explain how you made your decisions in parts a. what details in the…
The element diagram has only one type of particle, the compound diagram has fixed - ratio bonded particles, and the mixture diagram has separate un - bonded particles.
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here is the chemical structure of butanal: ch₃ - ch₂ - ch₂ - c(=o) - h …
Another molecule of butanal An isomer of butanal A different compound
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examine the molecule below. check the box next to each functional group…
amine: 1 arene: 1 alkene: 1 alkyne: 1 alcohol: 0 aldehyde: 0 amide: 0 carboxylic acid: 0 ester: 0 ether: 0 ketone: 0
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learning target i can identify solids, liquids, and gases based on thei…
Liquid, Gas, Solid
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determine the relationship between structure a and structure b in each …
1. isomers 2. isomers 3. resonance structures
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how many different molecules are drawn below?
4
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science laboratory safety test 1. flammable materials, like alcohol, sh…
1. B. an open flame. 2. A. notify your instructor. 3. D. any time chemicals, heat or glassware are used. 4. C. advise your science instructor that you wear contact lenses. 5. C. a…
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how many different molecules are drawn below?
3
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electrons are the only parts of an atom that interact during chemical b…
interactions between atoms that are sharing, donating, or receiving electrons
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there are two main types of bonds: covalent and ionic. ionic bonds incr…
B. Ionic bond
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how many different molecules are drawn below?
3
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which of these structures shows how the pictured molecule will look aft…
(Without seeing the actual correct structure among the options, we can't provide a specific option identifier and text. But the process would be to select the option that shows th…
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pilar is having trouble keeping up in chemistry. she has tried taking m…
to find new ways to solve her problem
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part a: which molecular level view contains a homogeneous mixture consi…
(No answer given in the image. Need to analyze the images to find the one with uniformly - mixed Ne and Kr atoms.)
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choose the correct answer. what is one type of synthetic polymer that i…
plastic
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use this condensed chemical structure to complete the table below. oh |…
Number of carbon - carbon single (C - C) bonds: 1 Number of carbon - hydrogen single (C - H) bonds: 4 Number of oxygen - hydrogen single (O - H) bonds: 2 Number of lone pairs: 4
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use this condensed chemical structure to complete the table below. ch₃ …
number of carbon - carbon single (C - C) bonds: 2 number of carbon - hydrogen single (C - H) bonds: 8 number of carbon - carbon double (C = C) bonds: 0
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use this condensed chemical structure to complete the table below. ch₃ …
number of carbon - carbon single (C - C) bonds: 1 number of carbon - hydrogen single (C - H) bonds: 6 number of carbon - carbon double (C = C) bonds: 1
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choose the correct answer. what type of carbon bond strengthens the sta…
sigma bonds
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use this condensed chemical structure to complete the table below. ch₃—…
number of carbon - carbon single (C - C) bonds: 0 number of carbon - hydrogen single (C - H) bonds: 6 number of lone pairs: 6
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what shell contains the valence electrons for an aluminum atom? innermo…
outermost shell
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use this condensed chemical structure to complete the table below. the …
number of carbon - carbon single (C - C) bonds: 1 number of carbon - hydrogen single (C - H) bonds: 6 number of lone pairs: 6
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use this condensed chemical structure to complete the table below. ch₂=…
number of carbon - carbon single (C - C) bonds: 0 number of carbon - hydrogen single (C - H) bonds: 4 number of carbon - carbon double (C = C) bonds: 1
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write in any formal charges not equal to zero. if there are none, pleas…
There are no missing formal charges.
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what would be a good title for the graph solubility in water (g/ml) tem…
Solubility of NH3 and NaCl at various temperatures
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according to newtons first law of motion, an object at rest will remain…
B. an unbalanced force
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how many ml of liquid are in this burette? 20 21 21.6 ml 23.8 ml 20.38 …
20.38 mL
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besides using some measure of science, alchemists resorted to using to …
# Breve explicación: Los alquimistas, aparte de ciertos métodos científicos, recurrieron a elementos místicos. La magia era una de las herramientas que utilizaban para intentar al…
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alchemy was practiced ____. by modern chemists in the middle ages by re…
# Breve explicación: La alquimia fue una práctica que se desarrolló principalmente en la Edad Media. No es practicada por los químicos modernos, ya que la química moderna se basa …
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15. how many neutrons are in the nucleus of an atom that has an atomic …
11
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match the vocabulary words with their definitions. 1. the rebirth of tr…
# Breve explicación: 1. El renacimiento se asocia con el renacimiento del verdadero aprendizaje. 2. La alquimia era el intento de transformar metales básicos en oro a través de un…
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match the vocabulary words with their definitions. 1. the rebirth of tr…
# Breve explicación: 1. El renacimiento se asocia con el renacimiento del verdadero aprendizaje. 2. La alquimia era el intento de convertir metales básicos en oro a través de una …
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how many different molecules are drawn below?
3
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match the vocabulary words with their definitions. 1. the rebirth of tr…
1. Renaissance 2. alchemy 3. science 4. philosopher 5. scholastics 6. summa 7. base metals 8. atom