化學
化學反應、化學計量、分子結構與元素性質。
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13. functional groups are key groups of atoms in biological molecules. …
13. The carboxyl functional group (-COOH) has a carbon - oxygen double - bond and a hydroxyl group on the same carbon, can ionize, and is polar. 14. An acid donates a proton. Lact…
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people take ______ to get adequate amounts of essential nutrients that …
A. dietary supplements
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the three dimensional structure of molecules is a consequence of the ar…
1. C. electrons 2. C. valence
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question 5. which of the following is not a chemical change? rusting of…
Converting water into steam
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homework 5 - 09/17/2025 question 4. which of the following is not a phy…
Gasoline burning
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when the central atom has one or more lone pairs, the molecular geometr…
1. A. trigonal pyramidal 2. E. linear
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electron - pair geometry are based on the number of regions of electron…
2 pair: linear 3 pair: trigonal planar 4 pair: tetrahedral
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question 3. classify each of the following as a physical or chemical ch…
a) Physical Change b) Chemical Change c) Chemical Change d) Physical Change e) Chemical Change f) Physical Change g) Chemical Change
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the procedure used in vsepr theory to determine the electron pair geome…
First question: Lewis structure Second question: electron density
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the wedge and dash notation is used to draw molecules from a three dime…
First question: plane of the page Second question: tetrahedral, trigonal pyramidal
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question 2 a chemical change is a change in which one or more substance…
One example could be rusting of iron.
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the electron - pair geometry and the molecular geometry will be differe…
1. C. lone pairs 2. E. tetrahedral
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1. make a claim about how soap affects hydrogen bonds between water mol…
1. Soap disrupts hydrogen bonds between water molecules. 2. Evidence: [Describe relevant data from the experiment, e.g., lower number of water droplets on penny with soap compared…
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electron - pair geometries describe all regions where electrons are loc…
Question 1: D. bonding pairs Question 2: D. molecular structure
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you should be able to answer the following questions before beginning t…
The volume of the liquid in mL is 3700 mL and in cm³ is 3700 cm³.
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in the vsepr theory model, basic electron - pair geometries arise when …
1. C. maximized 2. True
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question 3 the vsepr theory model only considers electron - pair attrac…
Question 3: B. repulsions Question 4: C. linear
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jennifer is buying a new pair of skates. there are 8 styles of skate to…
16
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the three - dimensional structure of molecules can be described in term…
1. B. distances, angles, arrangements 2. C. electron pairs
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24. a student measured the volume of a liquid to be 215.5 ml. the corre…
24. Approximately $4.87\%$ 25. Approximately $9.26\%$
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create an appropriately labeled bar graph to illustrate the sample mean…
1. Claim: Soap disrupts hydrogen bonds between water molecules. 2. Evidence: Differences in surface - tension related measurements (e.g., number of water drops on penny) between p…
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use the following figure to answer the question. a. 1 mole of the compo…
a. 60 grams. The molecule has 2 C (2×12 = 24 g), 4 H (4×1 = 4 g) and 2 O (2×16 = 32 g), and 24 + 4+32 = 60 g. b. The functional group is a carboxyl group (-COOH). The molecule is …
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11. in chemistry there is a saying \like dissolves like,\ which means t…
a. Water is polar. Water has a bent molecular shape and a significant electronegativity difference between oxygen and hydrogen atoms, creating a dipole moment. b. Oil is non - pol…
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10. consider the polar molecules in model 2. a. in general, the presenc…
a. Electronegative elements like O, N, F. b. High electronegativity to create dipole moments. c. Yes, under certain conditions such as reaction with polar substances or change in …
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measuring volume 8. 9. 10. 11. what is the volume of the rock? 12. why …
20 mL
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ch. 3 - matter quiz started: sep 16 at 7:25pm quiz instructions questio…
calcium
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question 9 which of the following elements would be a good choice for e…
B. copper
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ch. 3 - matter quiz started: sep 16 at 7:25pm quiz instructions questio…
fluorine, helium
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question 7 which of the following set of substances are only compounds?…
CH₄, CO, HI
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question 6 which of the following are pure substances? select all that …
oxygen, carbon dioxide
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question 5 pure substances can be classified into what groups? select a…
elements compounds
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question 4 a chemical change results in a change in the composition of …
True
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question 3 which of the following is a chemical change? grass is cut by…
food is digested in your stomach
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question 2 which of the following are physical properties? select all t…
methanol boils at 148.5 F, Solid sulfur is yellow
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question 1 which of the following is a physical change? ○ a pencil is s…
a pencil is sharpened
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ch. 3 - compound names & formulas started: sep 16 at 7:12pm quiz instru…
sodium sulfide
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ch. 3 - compound names & formulas quiz started: sep 16 at 7:12pm quiz i…
D. iron (III) chloride
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question 12 what is the formula for strontium oxide? sro sr₂o₃ sr₂o sro₂
SrO
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question 10 what is the name of licl? lithide chlorine lithium (i) chlo…
lithium chloride
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ch. 3 - compound names & formulas quiz started: sep 16 at 7:12pm quiz i…
C. $MgCl_{2}$
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how many sig figs? determine the number of sig figs for each of the fol…
14) 3 15) 4 16) 3 17) 1 (assuming measured to the nearest kg) 18) 5 19) 5.49×10⁶ m 20) 31,950 cm² (or 3.195×10⁴ cm²) 21) 192.67 cm³ 22) 790 cm (or 7.9×10² cm) 23) 3 24) 5 (assumin…
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write the complete electron configuration for each of the following: pa…
Part A: 1s^22s^22p^3 Part B: 1s^22s^22p^63s^23p^4
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1. equilibrium & molecules . equilibrium = molecules are balanced on bo…
1. Molecules are balanced on both sides and keep moving both ways at equilibrium. 2. No, molecules do not stop moving at equilibrium.
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the image shows a representative sample of 50 atoms of a fictious eleme…
Le - 19: 40% Le - 17: 20% Le - 15: 40% Average atomic mass: 17.3933 u (There may be a small difference from the provided answer 17.566 due to possible counting or rounding differe…
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at the chemical level, ____ are the smallest units of matter. o organel…
C. atoms
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select the correct answer. the image shows a portion of the periodic ta…
C. fluorine and chlorine
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select the correct answer in the periodic table of elements, what do al…
C. Each element is an alkaline earth metal
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complete the following information for chlorine # of protons # of elect…
| Element | # of Protons | # of Electrons | # of Neutrons | Total Number of Particles | Group | Period | | ---- | ---- | ---- | ---- | ---- | ---- | ---- | | Chlorine | 17 | 17 | …
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complete the following information for neon. # of protons # of electron…
| # OF PROTONS | # OF ELECTRONS | # OF NEUTRONS | TOTAL NUMBER OF PARTICLES | GROUP | PERIOD | | ---- | ---- | ---- | ---- | ---- | ---- | | 10 | 10 | 10 | 30 | 18 | 2 |
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complete the following information for fluorine # of protons 9 # of ele…
| Element | # of Protons | # of Electrons | # of Neutrons | Total Number of Particles | Group | Period | |---|---|---|---|---|---|---| | Sodium | 11 | 11 | 12 | 34 | 1 | 3 | | Mag…
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chemistry: fundamentals and principles presented by macmillan learning.…
Metals: Cu, K, V Nonmetals: Kr, I, O
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question 15 of 16 match each element to the appropriate group on the pe…
Alkali metal: Lithium, Francium Alkaline earth metal: Barium, Beryllium Halogen: Fluorine, Bromine Noble gas: Krypton, Helium
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complete the following information for helium. # of protons 2 # of elec…
| Element | # of Protons | # of Electrons | # of Neutrons | Total Number of Particles | Group | Period | | ---- | ---- | ---- | ---- | ---- | ---- | ---- | | Helium | 2 | 2 | 2 | …
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question 13 of 16 the statements either define or are closely related t…
1. Group 2. Period 3. Period 4. Group
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complete the following information for lithium. # of protons # of elect…
| # OF PROTONS | # OF ELECTRONS | # OF NEUTRONS | TOTAL NUMBER OF PARTICLES | GROUP | PERIOD | | ---- | ---- | ---- | ---- | ---- | ---- | | 3 | 3 | 4 | 10 | 1 | 2 |
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determine the element symbol, mass number, and charge for an atom or io…
element symbol: Sr mass number: 87 charge: +2
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determine the element symbol, mass number, and charge for an atom or io…
# Explanation: ## Step1: Identify the element The atomic number is equal to the number of protons. With 38 protons, the element is strontium, symbol Sr. ##[SSE Completed, Client C…
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wendy complete the following information for hydrogen. mass - proton # …
| # OF PROTONS | # OF ELECTRONS | # OF NEUTRONS | TOTAL NUMBER OF PARTICLES | GROUP | PERIOD | | ---- | ---- | ---- | ---- | ---- | ---- | | 1 | 1 | 0 | 2 | 1 | 1 |
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determine the number of neutrons, protons, and electrons for a bromide …
number of neutrons (bromide ion): 42 number of protons (bromide ion): 35 number of electrons (bromide ion): 36 element symbol (second ion): Fe number of protons (second ion): 26 n…
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question 11 of 10 > chemistry: fundamentals and principles presented by…
1. + 3 2. 0 3. - 3 4. + 1
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question 2 why is water tested also when testing for carbohydrates? it …
Question 2: Water is tested as a control to provide a baseline for comparison since it does not contain carbohydrates. What chemical indicator is used to test for the presence of …
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question 10 of 10 > use the atom - builder interactive to classify each…
Positive ion: three protons, three neutrons, and two electrons; one proton, one neutron, and zero electrons Negative ion: one proton, zero neutrons, and two electrons Neutral atom…
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/th grade poetry vocabulary worksheet name and class period_ part a - m…
1. C 2. D 3. E 4. B 5. A
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the image shows a representative sample of 50 atoms of a fictious eleme…
(You need to count the actual number of spheres in the image to get the specific values. For example, if there are 20 red spheres, 15 light - blue spheres, and 15 dark - blue sphe…
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question 3 of 16 the image shows a representative sample of 50 atoms of…
Le - 19: 20% Le - 17: 24% Le - 15: 56% Average atomic mass of Le: 16.80728 u
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noemi is writing an essay on organic foods. she wishes to include prope…
She could summarize the ideas from the source. She could paraphrase the ideas from the source. She could directly quote the ideas from the source.
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how many grams of neon, ne, would contain the same number of atoms as 2…
$20.18$
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13. list three common household items. identify one chemical property o…
1. Vinegar, its chemical property is reactivity with baking - soda. 2. Baking Soda, its chemical property is thermal decomposition. 3. Steel Wool, its chemical property is rusting…
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how many atoms are in 165 g of calcium? 165 g = atoms
$2.48\times 10^{24}$
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first and last name:alyssa lolley block:3rd assignment 9 the water cris…
Fossil Water - D Desalination - A Groundwater - C Replenish - F Tributaries - G Irrigation - B Scarcity - E Pollution - H
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calculate the number of atoms in a 5.39×10³ g sample of lithium. number…
$4.687\times 10^{26}$
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question 11 of 14 > a zinc ring is composed of 2.59×10²³ atoms. calcula…
$28.1$ g
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for the each element, convert the given mole amount to grams. how many …
For potassium: 2.21 g For cobalt: 32.4 g For selenium: 62.4 g
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convert 1.00 g of each element to moles. how many moles of magnesium ar…
$1.00\ g\ Mg\approx0.0411\ mol$ $1.00\ g\ Mn\approx0.0182\ mol$ $1.00\ g\ He\approx0.2498\ mol$
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material safety data sheets 1. locate and demonstrate the use of materi…
A. To provide chemical - related safety info including hazards, handling, storage, and emergency response. B. For example, for ethanol, search on manufacturer or safety database w…
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isotopes of the same element have different numbers of _. neutrons prot…
A. neutrons
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determine the chemical formula for each of the compounds. sodium perchl…
sodium perchlorate: $NaClO_4$ potassium permanganate: $KMnO_4$ calcium sulfate: $CaSO_4$ lithium cyanide: $LiCN$
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the modern atomic theory has been updated over the years as new observa…
The changes make the theory stronger because it has been tested and edited multiple times, making it more durable.
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determine the formula for each compound from its name. calcium sulfite:
$CaSO_{3}$
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determine the formula for each compound from its name. calcium sulfate:…
calcium sulfate: $CaSO_{4}$ chromium(III) fluoride: $CrF_{3}$ tetraphosphorus decoxide: $P_{4}O_{10}$
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match the scientist to his contribution to the atomic theory. match ter…
Rutherford - C Dalton - B Schrodinger - A
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determine the name for each compound from its formulas. k₂o: potassium …
Dinitrogen pentoxide
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determine the name for each compound from its formulas. k₂o: ni₂se₃: n₂…
Potassium oxide Nickel(III) selenide Dinitrogen pentoxide
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determine the name for each compound from its formulas. k₂o: ni₂se₃: n₂…
$K_2O$: Potassium oxide $Ni_2Se_3$: Nickel(III) selenide $N_2O_5$: Dinitrogen pentoxide
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write the formula for hydrobromic acid. formula:
HBr
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propiedades físicas y químicas definición dureza intensidad conductivid…
d. El silicio reacciona con el flúor para formar tetraflúoruro de silicio.
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4. ch₄ • elementos: • número de átomos: • relación: 5. c₆h₁₂o₆ • elemen…
# Explanation: ## Paso 1: Analizar los átomos en CH₄ El compuesto CH₄ está formado por carbono (C) e hidrógeno (H). Tiene 1 átomo de carbono y 4 átomos de hidrógeno. La relación d…
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write the formula for each compound. capitalization and subscripts are …
selenium tetrafluoride: $SeF_4$ oxygen difluoride: $OF_2$ dinitrogen monoxide: $N_2O$ phosphorus trichloride: $PCl_3$
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which sentence states a fact? crystals take about a week to form from a…
Crystals take about a week to form from a solution of water and sugar.
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give the systematic name of each covalent compound. spelling counts. sf…
SF₄: Sulfur tetrafluoride P₄S₃: Tetraphosphorus trisulfide CO: Carbon monoxide P₃N₅: Triphosphorus pentanitride
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tarea de trabajo de ciencias de séptimo grado: proporciones de átomos e…
# Explicación: ## Paso 1: Identificar elementos en H₂O El agua está formada por hidrógeno (H) y oxígeno (O). ## Paso 2: Contar átomos en H₂O Hay 2 átomos de hidrógeno y 1 átomo de…
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give the systematic name of each of the compounds. fecl₂: pbo₂: cubr: a…
1. Iron(II) chloride 2. Lead(IV) oxide 3. Copper(I) bromide 4. Gold(III) sulfide
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automotive chemicals and hazardous waste 1. define the following terms.…
C. A substance that can easily catch fire and burn. D. A substance that can destroy or damage other materials by chemical reaction, often by eating away at them. E. A substance th…
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7. alicias cheapskate boyfriend gave her a ring he claims is 24 carat g…
The volume of the ring is $1.5\mathrm{mL}$, the density of the ring is approximately $10.19\mathrm{g/mL}$ (it is likely not 24 - carat gold), and the mass of the solid object in t…
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1. distinguish between the characteristics of an unweathered rock and t…
1. An unweathered rock has smooth surfaces, sharp edges, and uniform color. A highly - weathered rock has rough surfaces, rounded edges, and color variations. 2. Chemical weatheri…
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automotive chemicals and hazardous waste 1. define the following terms.…
A. A substance or material with potential to harm human health or the environment. B. A substance that can produce adverse effects on living organisms.
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melting point data | compound | nacl | kcl | rbcl | cscl | mgf₂ | mgcl₂…
3. Los compuestos con altos puntos de fusión son iónicos. La fuerza de atracción entre iones depende de la carga y el radio atómico. Iones con carga más alta y radio más pequeño d…
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6. katie is doing a chemistry experiment and has 50 ml of a 25% solutio…
$6.25$ ml
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4. which type of fire extinguisher should be used for the following cla…
A. Water - based or dry - chemical fire extinguisher B. Dry - chemical, carbon dioxide, or foam fire extinguisher
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name date class melting point data compound nacl kcl rbcl cscl mgf₂ mgc…
Los compuestos con puntos de fusión altos son compuestos iónicos. La tendencia en los puntos de fusión se debe a la carga de los iones y el radio atómico. Compuestos con iones de …