化学
化学反应、化学计量、分子结构与元素性质。
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3. for the solutions formed below, calculate the standard enthalpy chan…
$17.9\ kJ/mol$ $-35.3\ kJ/mol$
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learn by doing the fermentation of sugar (glucose) to alcohol (ethanol)…
\(2.29\ L\)
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aluminum reacts with oxygen to produce aluminum oxide according to the …
1.16 L
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what is the volume of 16.7 g of oxygen gas at stp? 23.4 l 11.7 l 23.8 l…
11.7 L 1.98 L
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certain family dynamics, such as abusive parenting, can increase the su…
D. personality
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which compound features two hydrogen atoms and one oxygen atom, and is …
Water
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question 3 a 25.6 l tank of nitrogen gas is at 22.0 ^ { circ } mathrm {…
\(1.92\) ### Question 4
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question 1 hyperbaric therapy involves breathing high pressure oxygen. …
1740.4 torr 232 kPa 33.7 \(lb/in^{2}\)
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what type of reaction is shown below? 2kclo₃(s)→2kcl(s)+3o₂(g) synthesi…
decomposition
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actual mass of kcl used moles of kcl used mass of water initial tempera…
Trial 1 ΔT: - 1.0°C, qsystem: - 428 J, ΔH: - 17.1 kJ/mol Trial 2 ΔT: - 1.0°C, qsystem: - 429 J, ΔH: - 17.2 kJ/mol Mean ΔH: - 17.15 kJ/mol
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the element nickel is represented in the periodic table by its symbol, …
C. table's other 117 elements
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an atom of the element fluorine can be represented by the bohr model sh…
10
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the lewis dot diagram for an unidentified element is shown below. which…
chlorine
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question 8 a sample of argon gas is collected in a cylinder with a mova…
1.02 atm
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the movie below shows some molecules in a tiny sample of a mixture of g…
no
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question 7 a 15.0 l container is filled with methane, ch₄, gas at 50.0 …
\(PV = nRT\)
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the conservation of matter can be demonstrated by using chemical equati…
\(I_2 + 5Cl_2+6H_2O ightarrow2HIO_3 + 10HCl\)
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learninglab anatomy & physiology module 1: the human body & the chemist…
Hydrogen covalent bond
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identify the type of structure illustrated. chlorine molecule sodium ch…
Sodium chloride ionic bond
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benally, ceara physsci unit 4 cbm which of the following has the greate…
the proximity of the molecules of the medium
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question 5 a bubble released by a scuba diver at 10.0 m under water has…
Question 5: \(31.7\space mL\) Question 6: \(0.30\space atm\) Question 7: \(22.6\space g\)
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6 multiple choice 1 point what is the shape of the 3p atomic orbital? a…
D. A dumbbell
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identify the type of structure illustrated. water molecule iron molecul…
Water molecule
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identify the type of structure illustrated. magnesium sulfate compound …
Sodium chloride compound
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module 29 | extra practice: gas laws question 1 a 0.85 mol sample of a …
For question 1: \(12.7\space atm\) For question 2: B. \(1.33\space atm\)
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a spray can is used until it is empty except for the propellant gas, wh…
\(\frac{P_1}{T_1}=\frac{P_2}{T_2}\), \(3390\) torr (rounded to three significant figures)
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a gas occupies a volume of 2.45 l at a pressure of 1.03 atm at a temper…
The gas law equation is \(\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}\) and the volume \(V_2\) is \(2.88\space L\)
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a gas confined to a 462 cm³ container exerts a pressure of 107.4 kpa at…
The gas - law equation is $P_1V_1 = P_2V_2$. The pressure $P_2$ is $77.05$ kPa.
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determine the temperature of 2.49 grams of carbon dioxide gas that is i…
\(PV = nRT\)
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at a depth of 10 m, a diver exhales some carbon dioxide gas. when the b…
19.8
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a balloon is filled with 1.5 l of hydrogen at a temperature of 294 k an…
\(20.8\) L (rounded to one decimal place)
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these four elements are all in the same horizontal row (period) of the …
- **Same**: The number of electron shells. - **Different**: The number of electrons in the outer shell.
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did i get this a balloon contains 1.65 mol of argon gas and has a volum…
2.42 mol
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phet online lab, balancing chemical equations in this online lab you wi…
a) Reactants: \(CH_4\) (compound) and \(O_2\) (element). b) Products: \(CO_2\) (compound) and \(H_2O\) (compound). c) There are 4 hydrogen atoms in one molecule of methane. d) The…
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when subject to chemical weathering, which of the following rock types …
granite
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a sample of 6.25 mol of methane gas is trapped inside a cylinder with a…
3.02 L
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use your periodic table to answer the following. period
a. \(10\) b. \(2\) c. \(10\) d. \(8\) e. Neon (\(Ne\))
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e. element a. number of protons b. number of electron shells c. number …
a. \(8\) b. \(2\) c. \(8\) d. \(6\) e. oxygen
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classify the following as a suspension or colloid
Colloid
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a. number of protons b. number of electron shells c. number of electron…
a. \(6\) b. \(2\) c. \(6\) d. \(4\) e. Carbon
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classify the following as an element, compound, homogenous mixture, or …
Compound
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use your periodic table to answer the following. a. number of protons b…
a. \(7\) b. \(2\) c. \(7\) d. \(5\) e. Nitrogen (\(N\))
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which situation is the best example of translational motion? o a soccer…
a soccer ball passed between two players
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carbon and silicon are located in group 14 (4a) on the periodic table. …
Carbon has 2 shells of electrons, and silicon has 3 shells of electrons.
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what change has taken place in the following? k→k+ loss of a proton gai…
loss of an electron
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an atom becomes an ion with a - 1 charge because the atom gains one ele…
gains one electron.
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na + cl₂→ nacl total # before (reactants) elements total # after (produ…
The balanced equation is \(2\text{Na}+\text{Cl}_2 ightarrow 2\text{NaCl}\). - For \(Na\) in the table: Total \(\#\) Before (reactants) \(=2\), Total \(\#\) After (Products) \(=2\)…
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read these lines from \the raven.\ but the raven still beguiling my sad…
D. all of the above
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cao + c→ cac₂ + co total # before (reactants) elements total # after (p…
| Total # Before (reactants) | Elements | Total # After (Products) | |---|---|---| | \(1\) | \(Ca\) | \(1\) | | \(3\) | \(C\) | \(2 + 1=3\) | | \(1\) | \(O\) | \(1\) | The balance…
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balancing equations 1. h₂ + o₂ → h₂o 2. na + cl₂ → nacl 3. mg + o₂ → mg…
1. \(2H_{2}+O_{2}=2H_{2}O\) 2. \(2Na+Cl_{2}=2NaCl\) 3. \(2Mg+O_{2}=2MgO\) 4. \(4Fe + 3O_{2}=2Fe_{2}O_{3}\) 5. \(C+O_{2}=CO_{2}\) 6. \(N_{2}+3H_{2}=2NH_{3}\) 7. \(4Al+3O_{2}=2Al_{2…
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consider methane (ch4) how many molecules of methane do we have? how ma…
- How many molecules of methane do we have? \(2\) - How many TOTAL atoms of carbon do we have? \(2\) - How many TOTAL atoms of hydrogen do we have? \(8\)
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read the excerpt from \a modest proposal\ and the summary that follows.…
It effectively paraphrases the excerpt but does not correctly use a quotation.
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compounds and chemical equations how many atoms of carbon are in one me…
The number of carbon atoms is \(1\). The number of hydrogen atoms is \(4\).
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choose the sentence that shows correct capitalization. marie curie was …
Marie Curie was a Polish chemist who conducted pioneering research on radioactivity.
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using physical properties (page 48) 12. describe three steps that can b…
1. Observe physical appearance (color, texture, shape). 2. Test hardness (using a hardness scale). 3. Check density (calculate using mass and volume).
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a student is investigating how temperature affects particle movement in…
C. The particles move faster and become less compact.
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room a: arctic (0°c) room b: temperate (25°c) room c: tropical (40°c) t…
C. Room C, because higher temperatures increase the kinetic energy of scent particles.
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wei is taking a chemistry class with a new professor. he has high uncer…
A. active strategy
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use the bohr model below to answer the questions the element represente…
- The element represented by this model is \(Na\) - This element has 11 total electrons. - This element has 1 valence electrons. - This element has 3 energy levels of electrons.
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use the bohr model below to answer the questions: the element represent…
Energy levels: \(4\) Valence electrons: \(4\) Total electrons: \(14\) Element symbol: \(Si\)
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7 multiple choice 2 points what is geomorphology? the study of ancient …
- 7. The study of Earth's surface and how it changes - 8. Rocks and minerals - 9. Igneous rock
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what is the molar mass of aluminum carbonate al₂(co₃)₃? 234.0 g/mole 11…
234.0 g/mole
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what volume will 3.01 x 10^{23} molecules of gas at stp occupy? 44.8 l …
C. 11.2 L
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a dye has a percent composition of 75.95% c, 17.72% n, and 6.33% h by m…
C. \(C_5N_5H\), \(C_{15}N_3H_{15}\)
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how many moles is 24.5 g of silver? 0.227 mol 4.40 mol 83.4 mol 2640 mol
0.227 mol
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how many moles are in 2 x 10^{24} molecules of h_{2}o? 0.295 mole 3.32 …
B. 3.32 mole
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calculate the mass of 1.204 x 10^{24} molecules of water. 3.600 g 9.000…
36.00 g
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at stp, 18 l of o₂ would have a mass of how many grams? 13 g 26 g 40 g …
26 g
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what is the mass percent of water in calcium chloride dihydrate (cacl₂·…
24.51%
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what is the empirical formula of the molecule shown? ch c₂h₅ c₄h₁₀ ch₂
$C_2H_5$
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question 42 quarter 1 interim assessment the analytical chemist receive…
The chemist should use distillation. First, heat the mixture. At \(78^{\circ}C\), ethanol vaporizes. It is then condensed to collect liquid ethanol. Then, continue heating. At \(1…
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select the best definition. be sure to read all choices before making a…
D. arrangement
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written response elements in different groups of the periodic table ten…
Metals form cations by losing electrons (e.g., \(Na ightarrow Na^+\)), non - metals form anions by gaining electrons (e.g., \(Cl ightarrow Cl^-\)). The number of electrons lost/ga…
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comparing the properties of acids and bases warm-up sort each character…
- **Acids**: react with metals, taste sour - **Both**: can cause burns, conduct electricity - **Bases**: taste bitter
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23. a teacher designs a demonstration to show the similarity of the phy…
B ### 24.
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23. a teacher designs a demonstration to show the similarity of the phy…
- **Question 23**: B. The teacher uses a damp paper towel, which will cause a reaction to occur between the alkali metals and the water held in the paper towel. - **Question 24**:…
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21. which of the following is the correct representation of the electro…
A. \((0.1978)(10.01)+(0.8022)(11.01)\)
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21. which of the following is the correct representation of the electro…
B ### Question 22
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19. choose the group that does not contain isotopes of the same element…
D. Atom I has 82 protons, Atom II has 81 protons. Different number of protons means different elements.
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19. choose the group that does not contain isotopes of the same element…
D. Atom I: 82 protons, 126 neutrons; Atom II: 81 protons, 126 neutrons ### Question 20
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17. which is true of the $^{243}am^{3 + }$ ion? (a) protons 148 electro…
D. \(95\) Protons, \(92\) Electrons, \(148\) Neutrons
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17. which is true of the ^{243}am^{3+} ion? protons electrons neutrons …
D. 95 protons, 92 electrons, 148 neutrons.
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15. the initial mixture of all four substances can be classified as a _…
A. A = neodymium powder, B = ammonium chloride, C = benzoic acid, D = lead chloride
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15. the initial mixture of all four substances can be classified as a _…
A. heterogeneous; heterogeneous ### 16.
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use the information below to answer questions 13 - 16. a mixture of 4 s…
13. C. insoluble in water 14. B. allows the scientist to separate the alcohol from substance D by evaporating the alcohol
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12. air is composed of various compounds, including 78% of nitrogen (n₂…
C.
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use the information below to answer questions 13 - 16. a mixture of 4 s…
C. insoluble in water ### 14.
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use the data table below to answer question 9. 9. which atom has a net …
C. Atom Y
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12. air is composed of various compounds, including 78% of nitrogen $(n…
A
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use the data table below to answer question 9. 9. which atom has a net …
C. Atom Y
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use the data table below to answer question 9. 9. which atom has a net …
C. Atom Y ### Question 10
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use the information below to answer questions 7 - 8. 7. the diagram abo…
7. A (assuming diagram A shows \(CO_2\) molecules in a more dispersed state while still as \(CO_2\) molecules). 8. B
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questions 6 refers to the scenario below. in the lab, a quality assuran…
A.
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use the information below to answer questions 7 - 8. 7. the diagram abo…
## Question 7 A. ## Question 8 B.
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questions 6 refers to the scenario below. in the lab, a quality assuran…
A.
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use these answers for questions 1 - 4. note that some answers may be us…
1. B. Noble gases 2. C. Halogens 3. D. Transition metals 4. C. Halogens 5. B. All atoms of a given element must have the same number of protons, neutrons, and electrons.
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what is the maximum number of electrons the n = 4 shell can contain?
32
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how many orbitals does the n = 4 shell have?
16
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reference your periodic table to help you answer the following question…
C. Chlorine (Cl), because they are found in the same group.
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atomic theory and periodic table 1) which of the following statements b…
1. d. Electrons are in motion around a nucleus that contains protons and neutrons. 2. d. It has an equal number of protons and electrons.