化学
化学反応、化学量論、分子構造、元素の性質。
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a tamoxifen study claims that a combination of chemotherapy and the hor…
1. the first group of 361 that received tamoxifen alone 2. not blind.
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complete the rhyme scheme. a b b c d d life has loveliness to sell, mus…
A, B, C, B, A, C
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the model shows the chemical structure of a molecule. this molecule is …
nucleic acid
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19 what is the role of peer review in scientific research? a to ensure …
19. A. To ensure that research findings hold up to scrutiny and were conducted ethically 20. D. Consult the Material Safety Data Sheet (MSDS) 21. D. Fabricating experimental resul…
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4. inorganic elements that cannot be synthesized by the body are called…
c. minerals
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which of these liquids would likely be alkaline in nature? vinegar milk…
None of the above
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6. how do the types of chemical bonds differ from each other? how are t…
Differences are in electron - transfer/sharing and atom types. Similarities are that they are forces holding atoms for stability.
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6. how do the types of chemical bonds differ from each other? how are t…
7. b. hydroxide ions 8. c. hydrogen bonds
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4) calculate the average atomic mass of the following: show all work!!!…
Boron average atomic mass: 10.9343 amu Sulfur average atomic mass: 32.047 amu Chlorine average atomic mass: 35.363 amu
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isotopes and average atomic mass 1) which of the following are not an i…
1) Can't answer without diagram details 2) Approximately 24.31 amu 3) Approximately 6.94 amu
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electronic configuration practice- use periodic table with electron con…
1. $1s^{2}2s^{2}2p^{6}3s^{1}$ 2. $1s^{2}2s^{2}2p^{6}3s^{2}$ 3. $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{6}$ 4. $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{1}$ 5. $1s^{2}2s^{2}2p^{6}3s^{2}3…
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use the phase diagram of substance x below to find the boiling point of…
(Actual value should be obtained by accurately reading the phase - diagram, here we just show the process. After reading the diagram accurately and doing the conversion, fill in t…
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select all the adjectives. dont include a, an, or the. lincoln loud cou…
chemist's
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a certain element consists of two stable isotopes. the first has an ato…
$63.55$ amu
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see if you can complete the following table using only what is on this …
| Element | Symbol | Atomic Number | Mass Number | Protons | Neutrons | Electrons | | ---- | ---- | ---- | ---- | ---- | ---- | ---- | | Lithium | Li | 3 | 7 | 3 | 4 | 3 |
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name the following ionic compound. fe₃(po₄)₂
Iron(II) phosphate
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what is the name of the compound with the formula cucro4? what is the n…
1. NO 2. $Cu_{2}CO_{3}$ 3. Dioxygen difluoride 4. Copper(II) chromate
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use the phase diagram of substance x below to find the pressure at whic…
6 atm
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what is the charge of ions formed from atoms of mg? what is the charge …
Mg: + 2 Ca: + 2
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consider the ions fe²⁺ and o²⁻. how many protons and electrons does eac…
protons in Fe²⁺: 26 electrons in Fe²⁺: 24 protons in O²⁻: 8 electrons in O²⁻: 10
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use the phase diagram of substance x below to find the melting point of…
- 23°C
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the pressure above a pure sample of solid substance x at - 162. °c is r…
7 atm
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the pressure above a pure sample of solid substance x at -162. °c is ra…
(The answer depends on the actual reading from the phase - diagram. Since the diagram is not fully legible for precise value extraction, a specific numerical answer cannot be prov…
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2.1 the nature of matter 1. in the atom, which particles are in constan…
1. d. electrons 2. Sodium chloride has different properties than sodium and chlorine. Sodium is a reactive metal, chlorine is a toxic gas, while sodium chloride is a stable, edibl…
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draw the lewis dot diagram for a be²⁺ cation.
$Be^{2+}$
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draw the lewis dot diagram for a neutral atom of o.
Place the symbol 'O'. Then put 2 dots on the top, 2 dots on the bottom, 1 dot on the left, and 1 dot on the right of the 'O' symbol.
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study the following phase diagram of substance x. use this diagram to a…
Solid It will sublime (change from solid to gas) It will melt (change from solid to liquid)
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study the following phase diagram of substance x. use this diagram to a…
Liquid It will vaporize It will vaporize
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10. factors affecting rate of dissolution which of the following factor…
A. Surface area, C. Agitation, D. Temperature
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11. experiment on rate of dissolution students add salt to four beakers…
B. Agitation
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13. explanation of solubility and temperature which statement best expl…
A. Increased temperature raises kinetic energy, allowing more solute particles to dissolve.
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the boiling point of a substance is the temperature at which the substa…
krypton
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study the following phase diagram of substance x. use this diagram to a…
Liquid It will vaporize It will freeze
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look at the text below. if there is an error with subject - verb agreem…
The number of protons in an atom is expressed by that element's atomic number on the periodic table.
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study the following phase diagram of substance x. use this diagram to a…
1. Liquid 2. It will vaporize 3. It will freeze
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c. to dilute the solution, add more salt. d. to dilute the solution, ad…
D. To dilute the solution, add more water.
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who was the agricultural chemist who developed peanut farming as a stra…
George Washington Carver
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8. diluting a saltwater solution 12 g of nacl (salt) are dissolved into…
# Brief Explanations: Dilution[SSE Completed, Client Connection Error][SSE Completed, Client Connection Error][LLM SSE On Failure]
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5. elements vs. compounds each of these options is either an element or…
5. A. A molecule with two oxygen atoms, B. An atom of Krypton, D. A molecule composed of one type of atom 6. A. Water is the solvent, and sugar is the solute. 7. A. 4 only 8. (Not…
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1. substance composition images a and b show two different substances. …
1. B. Images A and B are both molecules containing 2 atoms of oxygen., D. Image A is an element and image B is a compound. 2. B. The ice has melted, which is a physical change., C…
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1. substance composition images a and b show two different substances. …
1. B. Images A and B are both molecules containing 2 atoms of oxygen, D. Image A is an element and image B is a compound. 2. B. The ice has melted, which is a physical change, C. …
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question 28 an example of a catabolic process is o hydrolysis dehydrati…
Question 28: Hydrolysis Question 29: Alkaline (basic) Question 30: Helium
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question 25 1 pts an isotope of an element contains different numbers o…
Question 25: C. neutrons Question 26: B. stability of the atom when there are eight electrons in the outermost energy level. Question 27: A. hydrolysis
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study the following phase diagram of substance x. use this diagram to a…
1. Solid 2. Sublimation (change from solid to gas) 3. Melting (change from solid to liquid)
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question 22 1 pts atomic mass is determined by the number of: protons a…
Question 22: D. protons and neutrons Question 23: B. turn blue Question 24: C. synthesis
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question 19 1 pts the hydrogen isotope tritium consists of: one proton.…
Question 19: one proton and two neutrons. Question 20: Decomposition Question 21: all of the above.
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question 16 1 pts as the concentration of hydrogen ions (h+) increases,…
- Question 16: solution becomes more acidic. - Question 17: dehydration synthesis. - Question 18: All of the above
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question 13 1 pts ab + cd → ad + cb is an example of a(n) ____ reaction…
Question 13: B. exchange Question 14: A. electrons Question 15: D. all of the above
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select all that apply select all the statements that are true of the ph…
B. A medium such as air or water is necessary to conduct sound to our ears. C. Air molecules move in regular, wavelike patterns. D. It is created by a vibrating source.
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question 7 1 pts a magnesium atom has an atomic number of 12, an atomic…
12; 13; 10 ### Question 8
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question 4 1 pts an ionic bond is formed by: two or more positive ions …
Question 4: a positive and a negative ion attracting each other. Question 5: All of the above are true of acids. Question 6: protons.
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study the following phase diagram of substance x. use this diagram to a…
Solid Melts Remains solid
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study the following phase diagram of substance x. use this diagram to a…
Vaporize; Freeze
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study the following phase diagram of substance x. use this diagram to a…
Solid It will sublime It will melt
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a rock breaking in limestone due to groundwater slowly dissolving it ov…
a) Physical weathering
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fill in the blank question is the movement of air molecules brought abo…
Sound
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what were jim crow laws? laws guaranteeing civil rights of free black a…
1. C. laws enacted by southern states following Reconstruction that discriminated against Black Americans 2. A. de facto
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10. kim answered a help - wanted ad. the ad states that the job pays d …
$\frac{d}{6}$ ### 11.
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unlike clinical psychology, counseling psychology multiple choice invol…
C. focuses specifically on educational, social, and career adjustment problems.
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multiple choice question the movement of air molecules brought about by…
D. sound
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study the following phase diagram of substance x. use this diagram to a…
Solid; Sublimation; Remains solid
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sol snapshot - challenge yourself by answering the sol style questions …
1. b) Water freezing and expanding in rock cracks 2. c) Acid rain dissolving minerals in a rock
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11. give three examples of isotopes and their uses, not discussed in cl…
Carbon - 12 (used in radiocarbon dating, 6 protons, 6 neutrons, 6 electrons), Carbon - 14 (used in radiocarbon dating, 6 protons, 8 neutrons, 6 electrons), Uranium - 235 (used as …
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this exercise will lead you to verify that the average atomic mass of m…
\(2.499\) amu
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a scientist makes an acid solution by adding drops of acid to 1.2 l of …
40 drops were added. About $0.17\%$ of the solution is acid.
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a scientist makes an acid solution by adding drops of acid to 1.2 l of …
40
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write the composition of one atom of the $^{42}ca$ isotope. 14 × proton…
20 protons, 22 neutrons, 20 electrons
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how do the data in the graph answer this question? proportion soil orga…
Amount of carbon in the soil was greatest near the intermediate trees, followed by the tallest, and then shortest trees.
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3. where does the matter from burning propane come from? when propane b…
1. F: Some water vapor and carbon dioxide comes from the person who burns the propane - False. The person is not the source of the elements in water vapor and carbon dioxide from …
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exercise summary of atomic composition how many electrons, protons, and…
Protons: 94 Neutrons: 146 Electrons: 94
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question: 9 of 10 point (yes or no) (yes or no) (yes or no) x 16 g 2 cm…
D. Lua, because all the samples have identical properties
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37. the ionization energies for element x are listed in the table above…
1. C. Al 2. b. 2A
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22. in a laboratory, 178.8 g of water is separated into hydrogen gas an…
158.8 g
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for each item in column a, write the letter of the matching item in col…
17. c 18. a 19. d 20. e 21. b
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the only nonmetal that is a liquid at room temperature is _. enter the …
Bromo
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the only nonmetal that is a liquid at room temperature is _. enter the …
Mercurio
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which of the following are properties of nonmetals? select all that app…
A. pobres conductores de calor D. opacos y quebradizos
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which atom requires higher ionization energy to remove its valence elec…
Magnesium has a higher ionization energy than sodium, and sodium has a higher ionization energy than potassium. Magnesium's higher ionization energy compared to sodium is due to i…
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which of the following are properties of nonmetals? select all that app…
A. poor conductors of heat, D. dull and brittle
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section 3.2 changes in matter in your textbook, read about physical cha…
The mass of the oxygen gas produced is $158.8\ g$.
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which of the following statements are true about nonmetals? select all …
a. They tend to have higher melting points than metals. - Falso b. They can exist as solids, liquids, or gases. - Verdadero c. They make up the majority of the periodic table of e…
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which of the following statements are true about non - metals? select a…
# Breve explicación: - a. Los metales suelen tener puntos de fusión más altos que los no - metales. Esto es cierto. - b. Los no - metales pueden existir como sólidos, líquidos o g…
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section 3.1 properties of matter in your textbook, read about physical …
7. C. Chemical property 8. C. Chemical property 9. P. Physical property 10. P. Physical property 11. P. Physical property 12. C. Chemical property 13. P. Physical property 14. P. …
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bromine is sometimes used as a disinfectant in swimming pools instead o…
a. cloro
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a is generally a poor conductor of heat and electricity and has a wide …
c. No metal
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matching 13 points match each of the definitions with the correct vocab…
1. Geothermal energy 2. Recycling 3. Fossil fuels 4. Runoff 5. Conservation 6. Non - point source pollution 7. Compost 8. Ore
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multiple - choice question what is a covalent bond? atoms sharing elect…
B. Atoms sharing electrons with each other
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which is not a use for antimony? a fertilizers b bullets c alloys d ele…
# Breve explicación: El antimonio se utiliza en aleaciones para mejorar propiedades mecánicas, en balas debido a su dureza y en electrónica en componentes como diodos y transistor…
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one metal - like property of silicon is its ________, while a nonmetal …
# Breve explicación: El silicio es un semiconductor. Tiene un brillo (lustre) similar al de los metales, pero también tiene propiedades no - metálicas como una conductividad inter…
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what metalloid is used in glass to help prevent it from breaking or cra…
# Breve explicación: El boro se agrega a vidrio para mejorar su resistencia a los cambios bruscos de temperatura y prevenir la formación de grietas. Los metales y metales -oides c…
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which element is not a metalloid? a boron b aluminum c tellurium d anti…
# Breve explicación: Los metalloides son elementos que tienen propiedades intermedias entre los metales y los no - metales. Aluminio es un metal, no un metalloide. Los elementos b…
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how many valence electrons do metalloids have? a 2 - 4 b 3 - 6 c 1 - 2 …
# Explicación breve: Los metalloides son elementos químicos que presentan propiedades intermedias entre los metales y los no - metales. Generalmente, los metalloides tienen 3 - 6 …
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multiple - choice question how many electrons did each nitrogen atoms s…
3 electrons
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which of the following elements is not a metalloid? a boron b carbon c …
# Breve explicación: Los metaloides son elementos químicos que presentan propiedades intermedias entre los metales y los no - metales. El boro, el arsénico y el germanio son metal…
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which of the following elements is a metalloid? a boron b bismuth c alu…
# Breve explicación: Los metalloides son elementos químicos que presentan propiedades intermedias entre los metales y los no - metales. El boro es un metalloide, mientras que el a…
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which of the following elements is a metalloid? a boron b bismuth c alu…
# Breve explicación: Los metales son elementos que presentan características propias como conductividad eléctrica y térmica, maleabilidad y ductilidad. El aluminio (Al) es un meta…
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multiple - choice question how is a \single covalent bond\ shown with d…
With a one dash between symbols
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semimetals is a term which refers to _, a small group of elements that …
# Breve explicación: Los semimetales, también conocidos como metales - no metales o elementos semi - conductores, son un grupo de elementos químicos que presentan propiedades inte…
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which information must be included on a hazardous chemical label? (sele…
A. Precautionary statements B. Signal word D. Hazard pictogram
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which statement about the hazard communication standard is true? select…
The standard ensures that employees receive training and education about the proper use of chemicals.