化学
化学反应、化学计量、分子结构与元素性质。
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question 4 15 poin liquid nitrogen boils at - 195.8°c. express the boil…
77.4 ### Question 5
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7 which has the greatest impact on the temperature of the earths atmosp…
carbon dioxide
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4 multiple choice 2 points which of the following is not a benefit of c…
4. C. anything can be composted 5. D. photodegradable plastic uses sunlight to degrade, while green plastic uses soil bacteria to degrade.
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49. if the pressure of 100 cm³ of a sample of air is doubled at constan…
D. $50\ cm^3$
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question 22 2 pts a male patient is here for his chemotherapy for metas…
Question 22: B. Z51.11, C50.021, C78.7 Question 23: A. S52.201A, V10.4XXA, Y92.831
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43. which of the following properties is exhibited by the ions listed: …
43. B. Isoelectronic 44. C. covalent bonds 45. B. CH₃CH₂COOH 46. D. I, II and III 47. B. 53.3% 48. D. baking powder
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35. when sodium hydroxide solution was added in drops and then in exces…
35. D. iron(II) ions 36. B. water 37. A. $Cl_2$ 38. C. fractional distillation 39. A. lattice energy 40. A. 5 41. B. selective discharge of ions 42. A. average velocity of the mol…
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a patient with metastatic bone cancer (primary site unknown) presents t…
Question 18: D. C79.51, E86.0 Question 19: B. G30.0, F02.80 Question 20: D. I12.9, N18.30
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a 22 - year - old patient status post - surgery, lower right leg amputa…
First question: A. T81.12XA, R65.21, A48.0 Second question: D. C79.51, E86.0
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28. the quantity of electricity that would deposit 2.7 g of aluminium d…
C. 28950 C ### 29.
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20. which of the following substances is not a diatomic gas at room tem…
- 20. D. $Br_2$ - 21. B. form stable compound with haemoglobin. - 22. D. there is a high electron density at the double bond in alkenes. - 23. A. helium. - 24. C. are highly elect…
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13. the deposition of ammonium chloride crystals on the walls of a test…
13. B. sublimation 14. D. propane 15. C. I and III only 16. C. fermentation 17. B. Different forms of an element in the same physical state. 18. C. 112 19. B. $NH_3$
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sources of hazardous wastes 5 how can organic compounds harm humans and…
5. Organic compounds can cause toxicity through ingestion, inhalation, or skin contact. 6. Heavy - metals are dense metals. They enter the environment via industrial processes, mi…
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what is hazardous waste? for questions 1 and 2, write true if the state…
1. True 2. False; unstable 3. Gasoline, paint - thinners, acetone 4. They can damage containers and react with other materials.
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an ekg technician is caring for a patient who is experiencing heart pal…
B. Holter monitor
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consider the balanced chemical equation. h₂o₂(aq) + 3i⁻(aq) + 2h⁺(aq) →…
- 0.00777, M/s
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question 23 2 pts a male patient is here for his chemotherapy for metas…
Question 23: C. C78.7, C50.021, Z51.11 Question 24: A. C79.51, C80.1, R11.10, Z51.0
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a patient was admitted three weeks following a normal vaginal delivery …
Question 15: A. O91.12 Question 16: C. Z00.121, H66.91, Z28.01 Question 17: B. C79.51, E86.0
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2) a toy balloon has an internal pressure of 1.05 atm and a volume of 5…
**Question 2**: The volume of the balloon will be approximately $6.9\ L$. **Question 3**: The volume of the gas will be approximately $770\ L$. **Question 4**: The volume of the l…
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11 matching 1 point identify each of the underlined items as a part of …
A sulfur molecule is composed of eight sulfur atoms: Microscopic domain Copper wire has a density of about 8 g/cm3: Macroscopic domain The mass of a lead pipe is 14 lb: Macroscopi…
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isotope symbol, element name, short name, atomic number, mass number, #…
| Isotope Symbol | Element Name | Short Name | Atomic Number | Mass Number | # of Protons | # of Neutrons | # of Electrons | | ---- | ---- | ---- | ---- | ---- | ---- | ---- | ---…
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complete the chart using your periodic table to determine the missing i…
| Isotope Symbol | Element Name | Short Name | Atomic Number | Mass - Number | # of Protons | # of Neutrons | # of Electrons | | ---- | ---- | ---- | ---- | ---- | ---- | ---- | -…
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question 4 aluminum has a density of 2.70 g/cm³. what volume is occupie…
D. 1.60 L
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5 matching 1 point identify the following properties as either extensiv…
volume - extensive density - intensive boiling point - intensive temperature - intensive heat - extensive
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numeric 1 point a large piece of jewelry has a mass of 132.6 g. a gradu…
$10.52\ g/mL$
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select the correctly punctuated sentence. a taylors favorite subjects a…
A. Taylor's favorite subjects are English and chemistry. A. The sweet, spicy sauce was the best that I'd ever tasted.
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home work chapter 1. please read the question carefully before submitti…
1. Dissolving of sugar in water: Physical 2. Condensation of steam: Physical 3. Burning of gasoline: Chemical 4. Souring of milk: Chemical 5. Melting of gold: Physical
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symbol 1 * choose single electron pair of electrons with opposite spins…
Atomic Orbital (region of space where an electron is likely to be found)
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the reduction catalyst in a catalytic converter helps to: ○ a. reduce t…
A. Reduce the oxides of nitrogen molecules into their base compounds.
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missed this? watch kcv: the rate law for a chemical reaction, we: deter…
rate = $k[\ce{NO2}][\ce{F2}]$
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substance a and substance b are mixed together. to separate the mixture…
Substance A is rice, and substance B is sugar.
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the boiling point of water is 100°c. the boiling point of acetone is 56…
Acetone will vaporize from the mixture before water.
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which method separates components of a mixture according to how quickly…
chromatography
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which method of separation would be most appropriate for separating a m…
distillation
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filtration is useful for separating: (1 point) compounds liquids from l…
solids from liquids or gases
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filtration is useful for separating: (1 point) compounds liquids from l…
solids from liquids or gases
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filtration is useful for separating: (1 point) compounds liquids from l…
solids from liquids or gases
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analyzing a specific reaction consider the following reaction: h₂ + 2ic…
2
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practice: perform the calculations below. round to the correct number o…
a) 1.3×10^6 b) 63 c) 13.4 d) 893917
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read the safety data sheet (sds) of hydrogen peroxide to identify the t…
B. Tightly fitting safety goggles
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3. data for chromiums four naturally occurring isotopes is provided in …
$51.998$ amu (rounded to three decimal places)
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which sentence contains a metaphor? the track star ran the race as fast…
The basketball player was a giant next to the small boy.
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identify 10 safety rules to keep in mind while working in the chemistry…
- A. Smell chemicals by wafting them rather than putting your nose in directly - B. Wear lab gloves as instructed - D. Do not pipet directly from or pour anything back into a reag…
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what is generally the best approach when liquid from a large reagent bo…
Pour some of the reagent from the bottle into a beaker, then use as needed in the procedure
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which chemical waste situation should always be supervised or performed…
Cleaning up a broken mercury thermometer
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answer the following. (a) a certain solution has a hydrogen ion concent…
(a) $7.25\times 10^{-6}$ (b) $2.8\times 10^{4}$
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important: if you use this answer in later parts, use the full unrounde…
$2.1\times 10^{-2}$ mol
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polonium has a mass number of 212 and an atomic number of 84. in a bala…
B. 82
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which statement about the balanced equations for nuclear and chemical c…
A nuclear equation is balanced according to mass number. A chemical equation is balanced according to the number of atoms before and after the change.
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energy release quick check which phrase describes transmutation? (1 poi…
the conversion of an atom of one element into a different element through nuclear changes
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energy release quick check which phrase describes transmutation? (1 poi…
the conversion of an atom of one element into a different element through nuclear changes
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energy release quick check the element radium has a mass number of 226 …
138
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part b in the first 22.0 s of this reaction, the concentration of hbr d…
$0.0011\ M/s$
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predict the rate of change in the concentration of i₃⁻ (δi₃⁻/δt). expre…
$0.0105\ \text{M/s}$
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name _ atomic structure notes hs pg 2 neutral atom a neutral atom has _…
Neutral Atom: A neutral atom has no net charge; meaning the charge is zero. In a neutral atom, the number of protons and electrons are equal. Example: Hydrogen atom (1 proton, 1 e…
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atomic structure notes ks pg 2 neutral atom a neutral atom has _ meanin…
1. The number of protons. 2. c. Protons are positively charged, located in the nucleus
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11 formula 0.5 points what is 146 g to mg? answer 12 fill in the blank …
11. 146000 mg 12. 2.79, 24 13. 0.30
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consider the balanced chemical equation. h₂o₂(aq) + 3i⁻(aq) + 2h⁺(aq) →…
$- 0.00350\ \frac{M}{s}$
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express the results of the following calculations with the correct numb…
Question 1: 3.1 Question 2: 0.548, g/mL Question 3: 296.3, K
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consider the balanced chemical equation h₂o₂(aq)+3i⁻(aq) + 2h⁺(aq) → i₃…
The change in the concentration of $H_2O_2$ per unit time $\frac{\Delta[H_2O_2]}{\Delta t}\approx - 0.0204M/s$
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give the correct number of significant figures for each of the followin…
0.0230 s⁻¹: 3 290 nm: amb 21.6 mL: 3 1.9500×10⁻³¹ kg: 5 0.00000745 mol: 7.45×10⁻⁶ mol 870,000,000 g (to 2 sig figs): 8.7×10⁸ g 1458.2 J: 1.4582×10³ J
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what is the value of the following operation to the correct sig figs an…
$2.15\ g$ ### Question 9
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give the correct number of significant figures for each of the followin…
amb 4 2 3
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select all of the following that represent homogeneous mixtures. brass …
Brass (an alloy made of copper and zinc), Salt water
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4. why do polymers allow the plastic bag to stretch and not leak when p…
Polymers are long chains of molecules that can move and seal around the pencil.
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4. why do polymers allow the plastic bag to stretch and not leak when p…
Polymers are long chains of molecules that can move and seal around the pencil
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traces of water can be removed from ethanol distillate by a. vacuum dis…
1. C. fractional distillation 2. A. lattice energy 3. D. 2 4. B. selective discharge of ions 5. A. average velocity of the molecules
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1. when pale - yellow dinitrogen(iv) oxide is heated in a closed contai…
B. nitrogen(IV) oxide is produced.
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15. if a heavy - metal has an unstable nucleus, the instability could b…
C. I and III only ### 16.
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which metalloid has three valence electrons? boron arsenic silicon lith…
boron
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the table shows columns that brenda uses for her notes on the propertie…
Only in the column for metals
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question 7 of 15 (1 point) | question attempt: 1 of unlimited sample of…
Change 1 is: a physical change Change 2 is: a chemical change Change 3 is: impossible
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based on their locations on the periodic table, which best compares the…
Arsenic has a more nonmetallic behavior than antimony because arsenic's atoms have fewer electron shells.
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which lists the elements in order from least conductive to most conduct…
nitrogen (N), antimony (Sb), bismuth (Bi)
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which element is a metalloid? selenium (se) germanium (ge) phosphorus (…
germanium (Ge)
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for metalloids on the periodic table, how do the group number and the p…
The lower the group number, the higher the period numbers, so the metalloids are found in a diagonal moving up from left to right.
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which statement describes a property that is unique to metalloids? meta…
Metalloids are semiconducting.
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13. the deposition of ammonium chloride crystals on the walls of a test…
13. B. sublimation 14. D. propane
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which property do metalloids share with nonmetals? both are gases at ro…
Both can react to form acidic compounds.
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which groups on the periodic table contain metalloids? groups 1-2 group…
Groups 13-16
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14. the product of decarboxylation of ch₃ch₂ch₂coona is a. propanoic ac…
14. D. propane 15. C. I and III only 16. C. fermentation
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6. which of the following liquids is a good conductor of electric curre…
6. C. Potassium chloride solution 7. C. 0.050 g 8. B. Sodium 9. C. is a saturated hydrocarbon 10. A. Group I 11. C. double decomposition reaction 12. A. $NH_3$
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20. which of the following substances is not a diatomic gas at room tem…
No correct option ### 21.
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(c) arrange the following compounds in order of increasing boiling poin…
$CO_2<CS_2 < NaH$
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under a third set of conditions, the sample depicted in c changes to th…
It depends on whether new substances are formed. If only the form or state changes (like melting, freezing, etc.), it's a physical change. If new substances are created, it's a ch…
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scenes a - d represent atomic - scale views of different samples of sub…
Physical change
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for each property listed, identify the type of element it describes. ve…
Very good electrical conductivity: Metal Amphoteric, able to form acidic OR basic compounds: Metalloid Gaseous at room temperature: Non - metal Solid at room temperature: Metal/Me…
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a friend cautions you against using any household chemicals because she…
D. a red herring
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(a) describe how the percentages of carbon and hydrogen in an organic c…
The organic compound is burned in excess oxygen. The mass of carbon - dioxide produced is measured. From the mass of carbon - dioxide, the mass of carbon in the original compound …
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(a) describe how the percentages of carbon and hydrogen in an organic c…
(a) Burn the compound in excess oxygen. Measure mass of \(CO_{2}\) and \(H_{2}O\) produced. Calculate mass of \(C\) and \(H\) using molar - mass ratios and then percentages. (b)(i…
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(a) the electron - configuration of carbon may be written as: 1s²2s²2pₓ…
(a)(i) See above explanation for symbols in $2p_x^1$. (a)(ii) Carbon forms four bonds to achieve octet by promoting an electron. (b)(i) Inductive effect is $\sigma$ - bond polariz…
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3a. explain the ff. terms: (i) primary alcohol (ii) secondary // (iii) …
- (i) An alcohol with -OH on a carbon bonded to one other carbon; Ethanol. - (ii) An alcohol with -OH on a carbon bonded to two other carbons; 2 - Propanol. - (iii) An alcohol wit…
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1. charcoal is burnt at 3.0g per second for 3 hours. calculate (i) volu…
(i) Volume of $CO_{2}$ at STP: $60480\ dm^{3}$ (ii) Number of moles of $O_{2}$ consumed at STP: $2700\ mol$ (2) (i) Source of $SO_{2}$: Burning of fossil fuels with sulfur - conta…
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why is radioactive dating important when approximating the age of earth…
Scientists can determine the order of when rocks formed on Earth.
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b. complete each sentence by choosing the correct word from the word bo…
1. Solution 2. Solute 3. Solvent 4. Unsaturated 5. Saturated 6. Supersaturated 7. Solubility 8. Miscible 9. Immiscible 10. Universal Solvent
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activity: solutions a. for each of the following mixtures, identify the…
1. Solute: Sugar; Solvent: Tea 2. Solute: Oxygen; Solvent: Nitrogen 3. Solute: Zinc; Solvent: Copper 4. Solute: Ethanol; Solvent: Water 5. Solute: Iodine; Solvent: Ethanol 6. Solu…
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activity: solutions a. for each of the following mixtures, identify the…
1. Solute: Sugar, Solvent: Tea 2. Solute: Oxygen, Solvent: Nitrogen 3. Solute: Zinc, Solvent: Copper
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two balloons hold two different gases. the gases are held at the same p…
the mass of each gas
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when the pressure of a gas decreases, which quantity will increase, ass…
B. V
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read the passage from sugar changed the world. we all crave sweetness, …
Sugar cane is no longer the main source of sweetness for most people