Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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1. this passage is mainly about a. stories from africa. b. advice about…
1. Sin conocer el pasaje, no se puede determinar con certeza, pero si se trata de la cafeína, podría ser relacionado con una planta que la contiene. Sin embargo, si no hay más con…
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how many formula units are in 5.5 moles of mgo? ?×10? formula units of …
$3.3121\times 10^{24}$ formula units of MgO
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which statements are true of heterogeneous mixtures? check all that app…
They settle out. They exhibit the Tyndall effect.
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what is the mass of 1.6 mol of cac2? molar mass cac2 = 64.10 g/mol 1.6 …
102.56 g
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which statements are true of solutions? they contain solutes and solven…
They contain solutes and solvents. Their particles must be evenly distributed. They are homogeneous matter.
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what equation shows the correct product and obeys conservation of mass …
Ba + I₂→BaI₂
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what is the missing coefficient to make a balanced equation? 2na + cl₂ …
2
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what is the missing coefficient to make a balanced equation? ?na + cl₂ …
2
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how much p is required to react with 2.7 grams of be to form 8.9 grams …
$6.2$ g
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which techniques would be best for separating a colloid mixture but wou…
B. centrifugation, F. long standing
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which techniques would be best for separating the solute from the solve…
distillation, boiling/heating, crystallization
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what is the molar mass of the covalent compound of2? of2 = ? $\frac{g}{…
54.00 g/mol
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what is the formula for carbon monoxide? co₂ co co₄ c₂o
CO
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what is the name of the compound c4n3? tetracyanide trinitride tetracar…
tetracarbon trinitride
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17 cl 35.45 56 ba 137.33 what is the molar mass of the ionic compound b…
$208.23$
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what is the molar mass of the ionic compound bacl2? bacl2 = ? $\frac{g}…
208.23 g/mol
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figure matter elements of period 2 atomic radius vs. atomic number in t…
Atomic Radius
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what is the name for the ionic compound lii? lithium iodine lithium ira…
lithium iodide
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what is the formula for the ionic compound of sodium and bromine? na is…
B. NaBr
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what is the formula for the ionic compound of sodium and bromine? na is…
NaBr
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what is the formula for the ionic compound of sodium and bromine? na is…
B. NaBr
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1. which type of change (phase or physical) is making lemonade? explain…
1. Physical change. Explanation: No new substances are formed; components can be separated physically. 2. Homogeneous mixture. Explanation: Uniform composition with evenly - distr…
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which statement below best describes this model? / ¿cuál de las siguien…
Oxygen atoms in other water molecules are also attracted to hydrogen atoms in other water molecules.
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which element will form an ionic bond with rubidium, rb? iodine, i cesi…
iodine, I
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which position on the graph represents two atoms that are not interacti…
Position 4
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1. sodium pentothal, also known as truth serum, is used by the c.i.a. t…
a. A solution (homogeneous mixture). b. Water is a polar solvent. Sodium pentothal is the solute. When placed in water, it dissociates into positive and negative ions. The partial…
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21. a good general rule about hearing protection is that it should be u…
21. a. 2 feet (61 cm) away 22. c. report it to a supervisor and avoid disturbing it 23. c. half mask or mouthpiece with a mechanical filter 24. d. paint 25. c. blood 26. c. extrem…
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identify the solutions (homogeneous mixtures) in the list below. check …
lead, an alloy of tin and lead window cleaner, a mixture of ammonia and coloring dissolved in water gasoline, a mixture of organic liquids with a fixed composition throughout
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which of the following is the correct bohr model for lithium, li? 3 li …
The Bohr model with 3 protons and 4 neutrons in the nucleus, 2 electrons in the innermost shell and 1 electron in the second shell.
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use this information to write the element in isotope notation. 11 p+, 1…
23
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use this information to write the element in isotope notation. 11 p+, 1…
11
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use this information to write the isotope notation for an element with …
Na
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using the element tiles, what element has 85 protons? rb cr at
At
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what does this model represent? a diatomic element an atom a compound
a compound
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this diagram represents a ______. mixture of compounds pure substance t…
mixture of compounds
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9. draw a bohr model for neutral li and the ion li+1 10. what are valen…
10. Valence electrons are the electrons in the outermost shell (highest - energy level) of an atom. They are involved in chemical bonding. 11. The first shell can hold a maximum o…
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read it! scientist albert einstein is revered as one of the greatest ph…
D. intersected
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unit 3a: the atom and the nucleus study guide 1. fill in the following …
1. | Subatomic Particle | Mass | Charge | Location | | ---- | ---- | ---- | ---- | | Proton | 1 amu (approx.) | Positive (+1) | Nucleus | | Neutron | 1 amu (approx.) | None (0) | …
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which best describes a compound such as sodium chloride? a pure substan…
a pure substance that can be separated into different elements by chemical means
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which sample is a pure substance? o zinc oxide o sugar dissolved in wat…
zinc oxide
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a solid precipitate is formed from the reaction of lead nitrate and sod…
C. filtration
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study guide atomic structure and the periodic table • know the 3 subato…
The average atomic mass of the element is approximately 87.55 amu and the element is Rubidium (Rb). 3) Gallium has a higher ionization energy than Potassium. This is because ioniz…
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which is a substance that is made up of only one type of atom? compound…
B. element
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the table shows the percentages of hydrocarbons that are found in a sam…
a mixture
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a chemist is studying an unknown substance and could break the substanc…
pure substance
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the table describes how some substances were formed. | substance | desc…
R
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which is a characteristic of mixtures? they are chemically bonded toget…
They can be separated by physical processes.
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7. iodine - 131 is used in the treatment of thyroid disease and has a h…
$0.005\ g$ ### 8.
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considering the passage about crude oil, why is distillation the main p…
Crude oil is a homogeneous mixture.
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of petroleum as motor oil or act, the oil that is removed from the e oi…
C. a mixture
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something to think about: if you discovered a new element that was adde…
s may vary. For example, one could name it after a favorite scientist like "Einsteinium" (similarly), or after a place like "Atlantium" if imagining a connection to Atlantis, or b…
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bisphenol a (bpa) is a chemical used to make polycarbonate plastics. po…
Ingested BPA may affect the brain, behavior, and reproductive development in fetuses, infants, and children.
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describe the best method for separating a mixture of sand, salt, and st…
3. Heat the mixture to evaporate the water. 2. Pour the mixture through a filter to separate the sand. 1. Pass a magnet over the mixture to remove the steel. 4. Add water to the s…
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answer the following questions and show your work in the space provided…
$0.03125$ g ### 2.
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you have been asked to write an essay about the chemical process of fir…
One of the three elements that are required for fire to burn is oxygen.
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a student studying acidity of juices did a taste test and determined th…
Juices with more sugar content have a lower pH.
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question 4 10 points compare and contrast \fog\ that is produced by dry…
Similarities: Both involve water vapor and are visible suspensions in the air. Differences: Dry - ice fog is created by the sublimation of dry ice (carbon dioxide) rapidly cooling…
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in which of these aspects do isomers differ? select all correct answers…
B. arrangement of atoms D. arrangement of bonds
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which do you think is the strongest type of covalent bond - a single, d…
C. triple
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according to the models of carbon - based molecules above, how many bon…
D. 4
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k/u - true or false question 11 (1 point) if $l = 2$, then we are refer…
Question 11: True Question 12: False
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question 10 (1 point) saved dipole - dipole forces are stronger than __…
A. London dispersion forces, a hydrogen bond
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table 1.1: data on measuring the freezing - point. concentration of sod…
The freezing point of the solution decreases as the concentration of sodium chloride increases.
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question 9 (1 point) which of the following is a polar molecule? pcl3 b…
A. $PCl_3$
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question 8 (1 point) saved which of following represents the electron g…
tetrahedral, v - shaped/bent
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question 7 (1 point) saved what is the correct order of bond polarity o…
C. C-Cl, P-Cl, Si-Cl
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a) create a line graph of concentration of sodium chloride in solution …
a) The line graph is created following the above steps with appropriate scales for x and y axes, points plotted, and lines connected. b) Generally, as the concentration of sodium …
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question 6 (1 point) which type of metallic alloy is formed when the me…
D. Substitutional alloy
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question 5 (1 point) which of the following elements is predicted to ha…
I
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using scientific measurements 24. a chemical reaction was carried out t…
24. b. precise 25. b. show the decimal place of the first digit 26. b. three 27. b. $6.5\times10^{- 5}$ cm 28. d. either a negative number or a positive number 29. b. is close to …
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question 3 (1 point) which of the following is the correct electron con…
[Ar]
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30. to determine the number of significant digits in a measurement, fol…
30. b. all non - zero digits are significant. 31. c. 0.026 g 32. b. \(1\times10^{-1}\) 33. c. \(1.000\times10^{2}\ g\) 34. a. it agrees closely with the accepted value. 35. a. Yes…
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question 2 (1 point) if l = 1, then what are the possible values for m_…
-1,0,1
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the measured mass and volume of three metal samples are shown. rank the…
Sample C, Sample A, Sample B
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you cannot classify matter based on chemical properties. o true o false
False
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kitchen chemistry 1. what are the essential ingredients for baking?(10 …
3. The proteins glutenin and gliadin in flour combine to form gluten, giving dough elasticity and structure. 4. Breads have more flour and yeast, rely on yeast - fermentation, and…
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knowledge check - 3 you come across a bottle of this product in the bac…
Look up the product on the Master Chemical List in the Environmental Compliance website. Treat as an Unknown spill if you can't find the chemical listing.
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9. when heating a substance, which of the following is true a. particle…
9. b. energy is absorbed 10. c. plasma 11. b. 5.34% 12. a. liquid 13. b. evaporation 14. e. condensing 15. e. condensing 16. d. melting 17. c. freezing 18. b. evaporation 19. d. m…
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question 6 (1 point) which chemical analysis test is most accurate? ¿qu…
There is not enough information to determine the answer as the accuracy of these tests can vary depending on what is being analyzed.
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question 6 (1 point) which chemical analysis test is most accurate? ¿qu…
There is not enough information to determine a single most[SSE Completed, Client Connection Error][SSE Completed, Client Connection Error][LLM SSE On Failure]
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question 6 (1 point) which chemical analysis test is most accurate? ¿qu…
(a) There is not enough information to determine which is most accurate as accuracy depends on various factors and the specific analyte being tested. Each of these (blood, spit, u…
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section 6 medical 3. the letter \s\ in the pneumonic paste refers to: a…
3. B. sputum 4. C. slower and less deeply 5. B. rapidly and deeply 6. C. croup 7. B. oxygen levels decrease; C. carbon dioxide levels increase 8. A. Altered mental status 9. B. pn…
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1) fill in the blank. the smallest unit of matter that still has the pr…
atom
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8) choose all that apply. which two molecules in the following reaction…
8) NaCl, H₂O 9) catalyst
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6) choose the best answer. are the molecules which are the result of an…
6) C. Products 7) B. reactants
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4) choose the best answer. what is known as the element of life? hydrog…
4. carbon 5. chemical reaction
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the smallest unit of matter that still has the properties of the matter…
2) D. molecule 3) D. atom
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calculation with sig figs video what does it mean when they say you can…
| Problem | Answer | Rounded Sig Fig # | | ---- | ---- | ---- | | 10.21 + 1.3 | 11.51 | 11.5 | | 12 + 2.54 | 14.54 | 15 | | 9.2 - 3.36 | 5.84 | 5.8 | | 87.398 - 86.50 | 0.898 | 0.…
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perform the following calculations and report your answers with the cor…
The first result is $4.52\times10^{34}$, and the second result is $9.8\times10^{-5}$.
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imagine that unknown gas in the storage tank is analyzed. a 28.05 - g s…
a) $p_{C_2H_6}=1.00\text{ bar}$ b) $p_{SO_2}=0.446\text{ bar}$ c) $p_{O_2}=1.01\text{ bar}$
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when the unstable compound ni3(s) decomposes, it produces nitrogen and …
0.00206
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perform the following calculations and report your answers with the cor…
$4.52\times10^{34}$ $9.8\times10^{-5}$
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part a what is the law of conservation of mass? matter can be created i…
Matter is neither created nor destroyed in a chemical reaction
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acrylonitrile is an important building block for synthetic fibers and p…
2190
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part a what is the definition of a physical property? what is the defin…
A property of a substance that can be determined or observed without changing the chemical composition of a compound is called a physical property. A property in which the chemica…
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part a what is the difference between a homogeneous - mixture and a het…
A heterogeneous mixture has two or more distinct regions that have different compositions. A homogeneous mixture has only one region and the composition of the mixture does not ch…
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what is a mixture? a mixture is composed of only one type of atom or on…
A mixture is composed of two or more pure substances that have been mixed together in a variable proportion
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what are the properties of a gas? a gas has a fixed volume, but will as…
A gas has no fixed volume or shape
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part b when carbon is burned in air, it reacts with oxygen to form carb…
96.8 g
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a sample of sodium reacts completely with 0.568 kg of chlorine, forming…
368 g