化學
化學反應、化學計量、分子結構與元素性質。
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a student removes a chemical sample from a reagent bottle to be used in…
A. Check and see if anyone else can use the chemical. If not, discard in the proper waste container.
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using the letters on the image, identify the significance of each secti…
s (matching each letter): A. Health B. Flammability C. Reactivity D. Special Hazards
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what is generally the best approach when liquid from a large reagent bo…
C. Pour some of the reagent from the bottle into a beaker, then use as needed in the procedure.
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what should you do after finishing work with a reagent bottle? select o…
A. Return the bottle to its proper storage location. D. Close the bottle.
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directions: indicate the correct number of significant figures in the f…
3 ### Problem 14: 967,000
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ordering 1 point predict the order of decreasing radius for germanium, …
1. cesium 2. potassium 3. germanium 4. bromine
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directions: write the following numbers in scie correct number of signi…
$4\times10^{-7}$ (1 significant figure) ### 2) For 500,000
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question 5 10 pts to make 100 g of a 5% (by mass, m/m%) aqueous sucrose…
5 g sucrose in 95 g of water. ### Question 6
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1 i aint no valedictorian. ill give you that. but im certainly not the …
Since no specific question is provided about this text, it's not possible to give a targeted answer. If you want to analyze the text from a literary perspective (subfield of Arts …
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this graph shows the results of an investigation in which the scientist…
Temperature
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pseudoscience across 3. the study of ufo’s and aliens, many believing t…
To solve this crossword, we analyze each clue: ### Across Clues: 3. Study of UFOs/aliens (pseudoscience): **Ufology** (length fits, topic matches). 4. Atlantic Ocean disappearance…
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which of the following statements does not apply to the reaction of cal…
It is a redox reaction. ### Second Question (Hydrophobic and Lipophilic Compound)
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pseudoscience page eclipsecrossword.com across 3. the study of ufo’s an…
To solve the crossword, we analyze each clue: ### Across 3. **Ufology** (study of UFOs/aliens, pseudoscience). 4. **Bermuda Triangle** (Atlantic area with disappearances, pseudosc…
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when dissolved in water one unit of calcium chloride produces ___ ions.…
3 (corresponding to the option "3") ### Question 2 (Solubility of Compounds)
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science connection diagrams and formulas for four molecular compounds a…
The next two compounds are \( \boldsymbol{C_5F_{12}} \) (diagram: 5 - C chain, ends with 3 F each, middle C with 2 F each) and \( \boldsymbol{C_6F_{14}} \) (diagram: 6 - C chain, …
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areas of study 3. is the following sentence true or false? the boundari…
True
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pseudoscience paige eclipsecrossword.com across 3. the study of ufos an…
To solve the crossword, we analyze each clue: ### Across Clues: 3. Study of UFOs/aliens: **Ufology** (pseudoscience about extraterrestrial contact). 4. Atlantic Ocean east of Flor…
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pseudoscience page across 3. the study of ufos and aliens, many believi…
To solve this crossword, we analyze each clue: ### Across Clues: 3. Study of UFOs/aliens: **Ufology** (pseudoscience about extraterrestrial contact) 4. Florida area with disappear…
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11 question (1 point) provide the correct iupac/systematic name for the…
1 - bromo - 2 - methylcyclohexane
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which tool is most appropriate for measuring the volume of a juice beak…
62 mL
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a ____ expels noxious fumes from a laboratory. ○ fume hood ○ fire blank…
A. fume hood
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chemistry 1 (lp-5061-ck-01) / lab safety evaluation a ____ can be used …
C. fire blanket and fire extinguisher (assuming options are labeled A - E with C as the selected one here; adjust label if needed, but the content is "fire blanket and fire exting…
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acid spills can be neutralized by adding ______. ○water ○distilled wate…
C. baking soda (assuming the options are labeled A: water, B: distilled water, C: baking soda, D: All of the above)
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when working with acids, always ____ to avoid chemical splattering. ∘ad…
B. add acid to water (Note: Assuming the options are labeled, with the second option being "add acid to water" as the correct one. If labels were different, adjust accordingly, bu…
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the _____ should be contacted immediately if you or anyone accidentally…
D. National Poison Control Center
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04 question (1 point) which of these compounds has the locator numbers …
The second compound (from the top of the options) has methyl substituents at locator numbers 2, 5, and 6. (Visually, this is the structure with methyl groups arranged such that th…
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which of the following structures is cyclopentane? 1st attempt choose o…
The second option (the pentagon - shaped cyclic structure)
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select the compound whose root name is hexane. 2nd attempt feedback cho…
The fifth compound (the one with the 6 - carbon parent chain, typically the structure with a hexagonal - like or straight - chain - with - branches arrangement that has 6 carbons …
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1. now you will investigate the emission spectra for a different elemen…
Yes, the emission spectra of helium will be significantly different from that of hydrogen. This is because hydrogen has one electron, and its energy levels follow a simple hydroge…
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atomic emission spectra purpose to view atomic emission spectra and use…
for Question 1 (example, hydrogen): 4 (or the number of lines visible in the simulation’s hydrogen spectrum)
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ion (ion sheet #3) ion – a charged atom with an overall charge due to a…
18
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ion class sheet #1 ion – an atom with an overall charge due to unequal …
+2 ### Question 50: ion?
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ion - oven atom with an overall charge due to unequal numbers of proton…
+2 (or specific to the table, but assuming a common ion, +2) ### 45. Element Symbol and Charge?
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ion - an atom with an overall charge due to unequal numbers of protons …
s: 39. Yes (or specify the ion, e.g., Cation/Anion; for the example, Cation) 40. 11 41. 10 42. +1 43. Yes (or specify the ion type, e.g., Cation) (Note: Adjust based on the actual…
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question 18 (5 points) listen pb has an atomic mass of 82. if an atom o…
D) an isotope.
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c) to make 550 ml of a 12% (by volume, v/v%) aqueous ethylene glycol so…
The volume of ethylene glycol is \(66\space mL\) and the volume of the solution is \(550\space mL\), so the answers are \(66\) and \(550\) respectively.
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a) to make 1000 g of a 10% (by mass. m/m%) aqueous glucose solution one…
100 g glucose in 900 g water. ### Part (b)
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19. element symbol with charge? type a response 20. overall charge? typ…
\( \text{Al}^{3+} \) (or \( \text{Ba}^{2+} \), etc. from the table) ### Question 20:
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read the poem \monet’s waterlilies\ by robert hayden. today as the news…
B. There is no rhyme scheme. C. The lines are unequal in length.
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what are the characteristics of fixed poetry? select three options. a r…
a. a regular rhyme scheme b. lines of equal length d. a set number of lines
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the rhyme pattern that occurs at the ends of lines in poetry is called …
D. a rhyme scheme.
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fill in the missing words a) when dissolved in water one unit of potass…
1, 1, 2 ### Part (b)
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3. oil spilt on the floor should be: a) left alone to evaporate b) wipe…
b. Wiped up immediately (note: there is a spelling error in the option, correct spelling is "immediately")
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(1) 1. oily or gas soaked rags should be: a) left on a bench to air out…
d. Stored in a steel container with an air tight lid
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7. corrosive means: a) acid b) a substance that is harmful to skin c) a…
c) A substance that eats or wears away another substance
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cash register schemes are a form of a) bribery. b) management fraud. c)…
D. employee embezzlement
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10 multiple choice 1 point when does an atom become a positively charge…
A. When it loses electrons
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if an employee overbills a company for travel, this would be considered…
A) expense scheme.
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multiple choice 1 point which of the following statements is true about…
A. They are negatively charged
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4 multiple choice 1 point what determines the atomic number of an eleme…
C. The number of protons
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3 multiple choice 1 point how many atomic mass units (amu) do protons a…
B. 1 (assuming the second option is labeled B, as the options are 2, 1, 4, 0 in order. If the numbering of options is different, adjust the label, but the value is 1)
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multiple choice 1 point where is the majority of an atom’s mass located…
B. In the nucleus (assuming the option "In the nucleus" is labeled as B; if the original labels were different, adjust the identifier, but based on the options, the correct one is…
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what defines an element and makes it unique from others? the number of …
The number of protons (the option "The number of protons")
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unit 1 exam: atomic structure & history name ______________________ dat…
B. protons in the nucleus ### Question 2
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fill in the missing words a) one of the ways to make 250 ml of a 0.077 …
s: a) Volume of 1.2 M NaOH: \(\approx 16.0 \, mL\) (or 16.04 mL), Volume of water: \(\approx 234 \, mL\) (or 233.96 mL) b) Volume of 2.5 M \( MgSO_4 \): \( 220 \, mL \) (Note: For…
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if an employee gives a false refund and pockets the cash, this would be…
B) cash register
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test your knowledge 1 match each term with the best description. - fire…
- "Tightly woven fabric used to smother and extinguish a fire" → Fire blanket - "Consists of absorbent material that can be ringed around a chemical spill until the spill can be n…
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what subatomic particles contribute to the charge of the atom? ○ proton…
C. electron and proton ### Second Question (Subatomic particle not in nucleus)
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the mass of an atom is primarily determined by the mass of its ___. ○ p…
C. protons and neutrons ### Second Question:
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what is the relative electrical charge of a proton? -1 +1 -2 0 question…
B. +1 ### Second Question (Nucleus of an atom)
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which is not part of daltons atomic model? ○ elements are composed of m…
Atoms of the same element can be different in size. ### Question 2
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\he wanted to do for psychology what the periodic table of the elements…
Wilhelm Wundt
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write the formula for the following covalent compound: selenium hexachl…
$\ce{SeCl_{6}}$
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write the formula for the following covalent compound: selenium hexachl…
$\ce{SeCl_{6}}$
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write the formula for the following covalent compound: selenium hexachl…
$\ce{SeCl_{6}}$
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write the formula for the following covalent compound: selenium hexachl…
$\ce{SeCl_{6}}$
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write the formula for the following covalent compound: oxygen difluoride
$OF_2$
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covalent compounds covalent compounds are composed of two nonmetal elem…
\( P_4S_3 \)
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write the formula for the following covalent compound: carbon tetrabrom…
$CBr_4$
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write the name of the following covalent compound: cl₂o₇
dichlorine heptoxide
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write the name of the following covalent compound: b₂cl₄
diboron tetrachloride
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write the name of the following covalent compound: p₂s₃
diphosphorus trisulfide
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write the name of the following covalent compound: p₂s₃
diphosphorus trisulfide
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write the name of the following covalent compound: p₂o₅
Diphosphorus pentoxide
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write the name of the following covalent compound: cbr₄
Carbon tetrabromide
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write the name of the following covalent compound: ncl₃
Nitrogen trichloride
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fill in the missing words a) one of the ways to make 250 ml of a 0.077 …
16.04, 233.96 ### Part (b)
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we are constantly bombarded with \information overload\ through newspap…
One time, I came across a social media post claiming that a popular brand of bottled water contained a chemical that caused cancer. Based on this information, I immediately stoppe…
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fill in the missing words a) washing soda is a hydrate of $na_2co_3$ th…
sodium carbonate decahydrate ### Part (b)
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which of the following provides the same protection as safety glasses? …
B. None of these
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consider the following reaction: co(g) + 3 h₂(g) ⇌ ch₄(g) + h₂o(g). if …
B. Concentrations of methane and water vapor are increasing.
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question 4 20 pts the reaction of decomposition of hydrogen peroxide h₂…
The option that does not apply is: As the reaction is occurring, the reaction mixture is cooling down by itself and the flask feels cold to the touch.
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true or false? exothermic reactions are always exergonic. ○ true ○ fals…
False ### Second Question (Which action does not speed up reaction)
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question 1 20 pts a thermochemical reaction of ammonia formation is: 3 …
The forward reaction is endothermic, and the reverse reaction is exothermic.
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tu désires neutraliser une solution basique. pour ce faire, tu utilises…
C. 0,030 mol
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in chemistry, the ph of a solution is a measure of the acidity or alkal…
\(5.22\)
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a scientist is working with methane (ch₄) and butane (c₄h₁₀). which sta…
They are compounds made of the same two elements, but each contain different numbers of atoms.
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which statement correctly describes a chemical reaction? reactants come…
C. Bonds between atoms break and reform. (Note: Assuming the options are labeled A, B, C, D with the third option being C. If the original labeling is different, adjust the identi…
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a researcher is designing a laboratory experiment to determine whether …
B. First, he should measure how long it takes for the liquid to become clear if X and Y are mixed together. Then, he should measure how long it takes if he also adds substance A t…
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a substance that influences the reaction but does not participate in th…
A. catalyst
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a student wants to create a liquid volcano. the student observes bubble…
The candy tablets being added to the drink.
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which statement best describes the amount of catalyst that remains at t…
The amount of catalyst is the same at the end as at the beginning of the reaction.
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if the activation energy required for a chemical reaction were reduced,…
A. The rate would increase.
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write the name of the following covalent compound: sif₄
Silicon tetrafluoride
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write the name of the following covalent compound: n₂i₃
dinitrogen triiodide
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write the name of the following covalent compound: n₂o
dinitrogen monoxide (or nitrous oxide, but systematic covalent name is dinitrogen monoxide)
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as an object - oriented computer programming language, perl is used by …
B. are not
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many studies have found a positive association between levels of dissol…
C. the effects of wastewater on the association between levels of dissolved organic carbon and mercury should not be taken as indicative of the effects of every type of human dist…
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8. pangaea is a: marks : 1.00 a. transition fossil d. vestigial structu…
E. Single supercontinent that existed 200 million years ago
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the time that it takes for half of a radioactive isotope to change into…
A. half - life