化学
化学反应、化学计量、分子结构与元素性质。
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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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listed in the item bank are key terms and expressions, each of which is…
Element: O, Pb Compound: $C_6H_{12}O_6$, NaCl, $MgCl_2$
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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
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name electron configuration is the ______________ of an atom or in atom…
Electron configuration is the distribution of electrons of an atom or in atomic orbitals. Aufbau principle - fill the lowest - energy Pauli Exclusion Principle - maximum of two el…
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mercury metal is poured into a graduated cylinder that holds exactly 22…
Mass: 306.0 g Volume: 22.5 mL Density: 13.6 g/mL
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review what you learned in foods 1 define the term food - borne illness?
Food - borne illness is an illness resulting from the ingestion of food contaminated with pathogens (such as bacteria, viruses, parasites), toxins, or chemicals.
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3 multiple choice 1 point what does the section the atoms show the read…
how the number of protons in an element affects where it is on the periodic table
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question 6 of 10 which of these uses ethos? a. yum organics has been pr…
A. Yum Organics has been providing well - rounded organic lunches to schools on the West Coast for more than 15 years.
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4. what are the 3 rules for naming acids? rule 1: rule rule 2: rule 3: …
Rule 1: Binary acids are named with "hydro -" prefix, non - metal root, and "-ic acid" suffix. Example: HCl is hydrochloric acid. Rule 2: Oxyacids with "-ate" anions are named by …
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19. bruno sees his lab partner mariah sneak into the science storage cl…
Yes. Mariah should not go in the science storage closet.
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unit 1: measurements - si units and unit conversions 1) si units: direc…
1. k 2. e 3. m 4. b 5. g 6. f 7. c 8. d 9. o 10. l 11. j 12. a 13. i 14. h 15. n 16. q 17. p
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17. in 1928, alexander fleming discovered a mold growing in one of his …
17. C. It led to investigations of other molds as possible sources of antibiotics. 18. C. C 19. C. Science views unexplained evidence suspiciously.
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2. fill in the table with each hydrated ionic compound formula scf₂·3h₂…
| Formula | Name | |--|--| | Cu(III)SO₄·5H₂O | Copper(III) sulfate pentahydrate | | MgSO₄·8H₂O | Magnesium sulfate octahydrate | | ScF₂·3H₂O | Scandium(II) fluoride trihydrate | |…
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question which of the following functions is not associated with the sk…
C. Synthesis of B vitamins
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practice problems: rules for equations: a) atoms must be equal on both …
a) $4P + 5O_2 = 2P_2O_5$ b) $FeCl_3+3NaOH = Fe(OH)_3 + 3NaCl$
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13. fill in the table below for ionic compounds with multivalent ions. …
| Formula | Name | | ---- | ---- | | $V(III)Br_3$ | Vanadium(III) Bromide | | $Ni(II)_3P_2$ | Nickel(II) Phosphide | | $Fe(II)O$ | Iron(II) Oxide | | $Fe(III)_2O_3$ | Iron(III) Ox…
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3. what is the relationship between the number of protons and the numbe…
In a neutral atom, the number of protons is equal to the number of electrons.
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11. fill in the table below for compounds with polyatomic ions. name: a…
| Name | Formula | |--|--| | Lithium Dichromate | $Li_2Cr_2O_7$ | | Calcium Sulfate | $CaSO_4$ | | Scandium(III) Nitrate | $Sc(NO_3)_3$ | | Silver Nitrate | $AgNO_3$ | | Ammonium …
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10. determine the formulas of each compound below: name: potassium sulf…
Potassium Sulfide: $K_2S$ Magnesium Bromide: $MgBr_2$
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define atomic mass number. what is the relationship between
The atomic mass number is the sum of the number of protons and neutrons in the nucleus of an atom.
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define atomic number. purpose: to determine infor
The atomic number is the number of protons in the nucleus of an atom.
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9. name each compound below: al3s2 au2o cacl2 naf name formula
Aluminum sulfide Gold(I) oxide Calcium chloride Sodium fluoride
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select the appropriate words from the list to fill in the blanks. a sol…
saturated solubility molar solubility solubility product
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abbey always gets zits on her chin and she cant figure out the best met…
1. Face - washing method 2. Number of zits on her chin 3. Using an acne face wash from the pharmacy will clear up zits on the chin faster than soap and water, organic oils, or jus…
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8. define each term: | |definition|examples| |--|--|--| |cation:|| |ani…
| | Definition | Examples | |--|--|--| | Cation | A positively - charged ion | $Na^+$ | | Anion | A negatively - charged ion | $Cl^-$ |
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7 multiple answer 1 point click all 3 of the properties of a metalloid.…
Brittle, Semiconductor, Shiny
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3. which of the following statements explains why atoms are always neut…
d. They have the same number of protons as electrons.
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2025 - quiz chapters 11 & 12 1. central chemoreceptors located in the m…
1. A. slight increases in carbon dioxide or a decrease in the pH of the cerebrospinal fluid. 2. C. have pulmonary edema and can follow verbal commands. 3. A. It forces the alveoli…
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2 multiple answer 1 point click all 5 of the properties that metal have…
B. Solid, C. Malleable, D. Ductile, E. Conductors
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2. which of the following statement(s) are true about the atoms of any …
a. The number of protons in an atom of an element is unique to each element. c. A proton is an atom of one element that is identical to a proton in an atom of another element.
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2. which of the following statement(s) are true about the atoms of any …
a. The number of protons in an atom of an element is unique to each element.
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1 multiple choice 1 point most of the periodic table is made of what ty…
B. Metals
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question 4 of 4 match the term related to the career options for cosmet…
trains stylists and salon staff to understand and use the company’s hair care, haircolor and other chemical service products - Manufacturer educator has experience, confidence, ad…
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7. describe how you can produce each type of spectra. a spectrum type e…
A. Emission spectrum: Produced by atoms/molecules transitioning from higher to lower energy states and emitting photons. B. Absorption spectrum: Produced when photons are absorbed…
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read this passage. identify tone and mood. from the onset of adolescenc…
Tone: Matter - of - fact; Mood: Discomfort and intrusion
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select the solvent that will most effectively dissolve nacl. o ch₃ch₂oh…
$CH_3OH$
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in chemistry, ph is a logarithmic scale used to specify the acidity or …
$5.01\times10^{-12}$
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which statement best describes evidence that a chemical reaction occurs…
The cake rises as gas bubbles form in the baking cake
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the molar mass of the solute can be determined by measuring which other…
$91.8g/mol$
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the atomic number comes from... a. the number of protons. b. the number…
A. the number of protons.