Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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table 1.4: concentrations of the six most common ions in seawater. ques…
### Pregunta 1 # Explicación breve: Los beneficios científicos, económicos y ecológicos justifican el costo. El conocimiento científico de los océanos puede llevar a avances en me…
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86 multiple choice 1 point a technician inadvertently shortens the disi…
Incomplete disinfection resulting in potential pathogen survival and transmission
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which of the following atoms would be electrically neutral? 10 protons,…
5 protons, 10 neutrons, 5 electrons
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84 multiple choice 1 point which of the following best describes the di…
D. Cleaning removes visible soil, disinfection kills most pathogens, and sterilization destroys all microorganisms including spores.
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83 multiple choice 1 point when using chemical sterilants such as ethyl…
D. Ensuring proper ventilation
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what best describes a limitation of the bohr model, which depicts elect…
Electrons move in a solar - system spiral around the nucleus in the modern atomic model. (This option highlights the incorrectness of the Bohr Model's fixed - orbit concept compar…
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silicon is the second most abundant element in the earth’s crust. it is…
28.1 amu
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79 multiple choice 1 point what should a medical assistant do with an i…
C. Clean it first to remove the organic material
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which of the following best represents a pair of isotopes? carbon - 12 …
Carbon-12 and Carbon-14
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based on the periodic table block for nitrogen shown below, what nuclei…
$_{7}^{14}N$
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the image below shows a model of a lithium atom. how many neutrons are …
4
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most of the ice found on earth is ice ih, distinguished by a crystallin…
B. amorphous ice lacks the thermal energy to form the crystals found in ice Ih.
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which statement best describes the particle diagram below? this is a mi…
This is a mixture of molecules/compounds.
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61 multiple choice 1 point a medical assistant notices a colleague cons…
D. Facilitated transmission of pathogens and an increased risk of healthcare - associated infections
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how did soldiers adapt to the use of chemical weapons? they began to we…
They began to wear protective masks and clothing.
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select the correct answer. who is the target audience for the passage? …
D. amateur gardeners
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53 multiple choice 1 point what is the primary purpose of a negative ai…
To prevent cross - contamination of airborne pathogens
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51 multiple choice 1 point in an outbreak involving multidrug - resista…
C. Increase cleaning frequency and use disinfectants effective against resistant strains
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in which group of elements does tellurium (te) belong? (1 point) transi…
C. metalloids
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based on patterns in the periodic table, which element is the least mal…
phosphorus (P)
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how does mercury differ from other metals? (1 point) it does not chemic…
It is not solid under normal conditions
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the titration of vitamin c with iodine proceeds according to the given …
$6.16\times10^{-5}\ mol$
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an element is highly conductive, highly reactive, soft, and lustrous. t…
B. alkali metals
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the titration of vitamin c with iodine proceeds according to the given …
$7.91\times 10^{-5}\ mol$
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which are career and technical student organizations? select six option…
Business Professionals of America DECA Future Business Leaders of America FFA SkillsUSA FCCLA
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8. describe the difference between a heterogeneous and homogeneous mixt…
A homogeneous mixture is uniform throughout and components are indistinguishable visually. A heterogeneous mixture is non - uniform and components are distinguishable or separable.
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nfpa 70e primarily aims to establish a safe working area for employees …
A. Electricity
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homework - due in class 9/18 (thursday) classifying matter - classify t…
6. Homogeneous 7. Heterogeneous 9. c. Are arranged in a regular geometric pattern 10. Draw separate H₂O molecules with hydrogen atoms (lightly shaded) and oxygen atoms (darker sha…
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bottles, cans, and plastics are ____________. biodegradable pollutants …
C. non - biodegradable pollutants
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which of the following is not a factor in determining the severity of a…
B. Color
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part 3a 12 marks choose 4 of 5 (lesson 3a) draw the following ionic bon…
a) Formula: $Li_3P$ b) Formula: $CaCl_2$ c) Formula: $Mg_3N_2$ d) Formula: $AlCl_3$ e) Formula: $KBr$
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in 1974, mexican chemist mario molina and us chemist f. sherwood rowlan…
B. Specifically
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question 8 a firefly uses specialized muscles to draw oxygen into its l…
B. By contrast
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while researching a topic, a student has taken the following notes: • m…
C. Cosmochemist Kentaro Terada set out to determine whether some of the Moon's oxygen was coming from Earth.
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10. ice melting is an example of a(n) ________ process. (1 point) endot…
A. endotérmico
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8. a process that absorbs energy from its surroundings, usually in the …
# Breve explicación: Un proceso endotérmico absorbe energía del entorno, generalmente en forma de calor. Un proceso exotérmico libera energía. La energía cinética se asocia con el…
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7. the amount of energy required to break a chemical bond is called kin…
# Breve explicación: La energía necesaria para romper un enlace químico se conoce como energía de enlace. La energía cinética se asocia con el movimiento de partículas, la energía…
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5. a process that releases energy to its surroundings, usually in the f…
# Breve explicación: Un proceso exotérmico libera energía al entorno, generalmente en forma de calor. Un proceso endotérmico absorbe energía. La energía cinética se asocia con el …
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2. fire burning is an example of a(n) ______ process. (1 point) endothe…
B. exotérmico
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question 12 why are hydrocarbons considered hydrophobic? the hydrogen b…
The covalent bonds between hydrogen and carbon are nonpolar
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english i - unit 1.1: informing your audience: how to/guide to - “how t…
Since the text of the essay "How to Poison the Earth" is incomplete in the provided image and no specific questions regarding text - structure and text - features are shown, we ca…
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b write the possessive form of each underlined noun. 8. the laboratory …
8. laboratory's 9. chemists' 10. computer's 11. men's 12. day's 13. chemist's
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question 4 what are compounds that have the same molecular formulas but…
Question 4: B. Isomer Question 5: D. Water Question 6: A. Glycogen
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question 1 how many covalent bonds are formed by carbon atoms, producin…
- Question 1: Four - Question 2: Functional groups - Question 3: - Carbohydrate: Monosaccharide - Protein: Amino - acid - Nucleic Acid: Nucleotide
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grammar: possessive nouns a possessive noun shows ownership. it always …
1. Underlined: library's; Type: singular 2. Underlined: children’s; Type: plural 3. Underlined: young adults’; Type: plural 4. Underlined: books’; Type: plural 5. Underlined: book…
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helium is a gas. which is true about its particles? helium cannot chang…
Helium particles are randomly spaced and moving freely.
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16. you are a research scientist working for an oil exploration company…
Carbon (C) and hydrogen (H) are likely to make up the molecule because non - polar covalent bonds are common between carbon and hydrogen atoms, and hydrocarbons with such bonds ar…
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17. true or false: an ionic bond is based on the transfer of electrons …
True
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calculate the missing information and then draw a bohr diagram and lewi…
| Element | # of P | # of N | # of E | | ---- | ---- | ---- | ---- | | Li | 3 | 4 | 3 | | Ne | 10 | 10 | 10 | | Mg | 12 | 12 | 12 | | Cl | 17 | 18 | 17 | | He | 2 | 2 | 2 | | Si |…
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14. what are the three ways in which atoms with incomplete valence shel…
14. Sharing electrons (covalent bonding), donating/accepting electrons (ionic bonding), van der Waals interactions 15. d. All of the above
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12. use the periodic table to determine the type of bond most likely fo…
a. Covalent bond b. Ionic bond c. Covalent bond d. Covalent bond e. Covalent bond f. Ionic bond
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do the math | energy efficiency the ratio of useful energy to the overa…
12.75 ### 21.
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18. many students have difficulty understanding how giving up an electr…
18. Atoms with nearly - empty outer shells become stable by losing electrons to achieve a full inner - shell configuration. 19. a. Hydrogen bond b. Covalent bond c. Nonpolar coval…
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which of the following is insoluble in water? select all that apply. hy…
Hydrophobic proteins, Small non - polar gases
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10. if a 2 kg object is thrown with a velocity of 10 m/s, what is the a…
10. 100 J 11. Rotational motion is the same thing as circular motion. 12. 9.81 13. C. Strong nuclear force 14. D. Weak nuclear force 15. D. Weak nuclear force 16. A. Electromagnet…
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10. complete the following table by filling each line with the correct …
| Element | Atomic number | Mass number | Number of protons | Number of neutrons | Number of electrons | |---|---|---|---|---|---| | Carbon - 12 | 6 | 12 | 6 | 6 | 6 | | Hydrogen …
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question 1 sensible perspiration released by the eccrine sweat glands s…
to cool the surface of the skin, to reduce body temperature, and to dilute harmful chemicals
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express each of these concentrations in parts per million (ppm). 4.0 mi…
4.0 ppm 0.004 ppm
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osha 10 hour construction: module 04 - ppe exam question 9 of 10 gloves…
D. Rubber or plastic
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matching 10 points used as a support used to perform small - scale chem…
Used as a support - wire gauze Used to perform small - scale chemical reactions - test - tube Used to create solutions - volumetric flask Used to spread the heat of a flame - wire…
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4 matching 10 points used to hold or transfer a liquid. these come in d…
1. beaker 2. crucible 3. evaporating dish 4. thermometer
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which would have a higher boiling point? 2.0 m nano₃ 1.5 m alcl₃ the bo…
1. 1.5 M AlCl₃ 2. 1.5 M AlCl₃
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question 6 of 29 between a 2.0 m aq. nano₃ and 1.5 m aq. alcl₃ solution…
1. B. $1.5\ M\ AlCl_3$ 2. B. $1.5\ M\ AlCl_3$
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3 matching 10 points used to hold test - tubes (as a support) used for …
1. Test - tube rack 2. Burette 3. Analytical balance 4. Burette
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2 matching 10 points used to weigh out a powder chemical used to transf…
Used to weigh out a powder chemical - weighing dish Used to transfer a solid chemical - scoopula Used to mix chemicals - stirring rod Used to separate an insoluble substance - fun…
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directions: match the definition on the left with the correct term on t…
1. Used to stop a liquid from flowing - cork 2. Used to support a crucible - clay triangle 3. Used to transfer a small amount of a liquid from one container to another - pipette 4…
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true or false: the general rule with chemical - resistant gloves is, th…
False
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science matter and energy 2nd ed test 5 chapter 5 match each descriptio…
1. F. Thermal energy 2. D. Gravitational potential energy 3. H. Wave energy 4. C. Electric potential energy 5. B. Elastic potential energy 6. A. Chemical energy 7. speed of light …
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select all the sentences that use the word inherent correctly. despite …
"Despite the project’s inherent challenges, she remained optimistic about the success of the new initiative." "The inherent value of a summer job is that it teaches you about the …
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which answer best represents the elements and atoms of each element pre…
B. 1 atom of calcium, 2 atoms of oxygen, and 2 atoms of hydrogen
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the periodic table of elements below are four elements. drag and drop e…
Carbon - C Chromium - Cr Chlorine - Cl Calcium - Ca
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the chemical formula for ethane is c₂h₆. which statement correctly desc…
B. 10 carbon atoms and 30 hydrogen atoms
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a compound is a substance formed when two or more chemical elements are…
C. $C_6H_{12}O_6$
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chemical compounds a compound is a substance formed when two or more ch…
C
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elements are pure substances. they are organized in the periodic table.…
B. Ca, C. Fe, E. Si, F. Na
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atoms may exist singly or be joined together. molecule is the general t…
B. The subscript "2" shows that two hydrogen atoms are bonded to one oxygen atom to create water.
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3 what are rocks with pores also called? a permeable rocks b impermeabl…
A. Permeable rocks
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chemical compounds atoms may exist singly or be joined together. molecu…
1. Which container represents a compound? C. $H_2O$ 2. What is the reason for including the subscript in the chemical formula for water? The subscript "2" indicates that there are…
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which answer best represents the elements and atoms of each element pre…
A. 1 atom of sodium, 1 atom of aluminum, 2 atoms of sulfur, and 8 atoms of oxygen
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the chemical formulas for several different substances are shown. selec…
$O_2$, $Fe$, $N_2$, $Al$, $C$
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eddies chemistry teacher has asked the class to add various household s…
B. weak base
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which compound is not a base? a nh₃ b naoh c hclo₄ d nh₄oh
C. HClO₄
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an acid - base neutralization always produces a salt and water. identif…
B. sodium chloride
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being used in experiments to test/ize whear in the picture above, the b…
D. It must be a base since it turns the blue - litmus paper red.
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a reaction between an acid and a base is called a(n) ____________ react…
C. neutralization
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naoh and bleach have several characteristics in common. which is not on…
B. They have a pH<7
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place the properties of acids and bases in the venn - diagram under the…
Acids: Tastes Sour, Has a pH less than 7 Bases: Feels slippery, Has a pH greater than 7, Tastes Bitter Acids and Bases: Conducts electricity
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part b according to the chart, which substance has the lowest oh- conce…
C. Battery Acid
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properties of acids and bases part a naoh and bleach have several chara…
B. They have a pH<7
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when excess stomach acid is treated with milk of magnesia mg(oh)₂ a rea…
B. a salt and water
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acids and bases. excess stomach acid is often treated with milk of magn…
C. 10.5
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27. never put extension cords or tools in aisle or door ways. (1 point)…
27. true 28. clean and organized 29. an approved flammable waste storage container 30. safety 31. all of the above
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read these lines: that conqueredst alexandria by the right of arms, and…
C. abaaaba
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32. flammable liquids need to be kept in closed safety __________ (1 po…
32. containers 33. true 34. false 35. true 36. true 37. should be worn by anyone who enters the shop
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1. refer to model 1. what subatomic particles do the following symbols …
1. “−” is an electron, “+” is a proton, “○” is a neutron. 2. (No table provided to complete, so no specific answer given here) 3. a. Hydrogen: 1, Carbon: 6, Magnesium: 12. b. The …
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summarizing your thoughts 7. what clues are given in chemical formulas …
Elements are represented by single or paired letters, compounds by combinations of element symbols with sub - scripts showing atom ratios.
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a student wants to test the idea that earth and meteorites formed from …
Measure the chemical composition of meteorites and igneous rocks.
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model 3: defining elements and compounds the model: fe is the elemental…
1. It indicates 2 chlorine atoms bonded together to form a molecule. 2. It implies 1 atom of that element in the formula unit. 3. False. 4. Element. 5. Similar to $Cl_2$, $S_8$ ha…
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q1 chemistry: u2l4 avg. atomic mass. pre - work part 1: average atomic …
1. 14 2. b. Nitrogen (N) 3. The average atomic mass is close to 14, and nitrogen has an average atomic mass of approximately 14.01 on the periodic table. 4. 32 5. b. Sulfur (S) 6.…
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use the periodic table to identify the elements that are present in the…
arsenic