化學
化學反應、化學計量、分子結構與元素性質。
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graded quiz: surface processes on earth 0:00:58 elapsed question 1 (5 p…
Question 1: C. haloclasty Question 2: C. nitrates
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isotopes and average atomic mass worksheet determine the weighted avera…
| Element | Average Atomic Mass | |--|--| | Iodine (I) | 126.86 | | Gold (Au) | 197 | | Carbon (C) | 12.04 | | Iron (Fe) | 55.85 | | Hydrogen (H) | 1.012 | | Nitrogen (N) | 14.03 …
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directions: label the following reactions as synthesis (s), decompositi…
1. D, 2NaCl → 2Na + Cl₂ 2. S, 2Na + Cl₂ → 2NaCl 3. C, C₂H₄ + 3O₂ → 2CO₂ + 2H₂O 4. D, 2H₂O → 2H₂ + O₂ 5. S, 2H₂ + O₂ → 2H₂O 6. C, 2C₈H₁₈ + 25O₂ → 16CO₂ + 18H₂O 7. DR, B, NaOH + HCl…
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question 24 1 pts how many particles are in 78.9g of mgbr₂? a. 4.75x10²…
D. $2.58\times 10^{23}$ particles
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give each group a title (what do they have in common?) chapter 3: matte…
Group 1: Graph and Variable Concepts Group 2: Physical Properties of Matter Group 4: Classification and Composition of Matter
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instructions many federal and state agencies regulate the beauty and we…
1. **Step 1: Research Federal and State Agencies** - Use government websites, industry publications, and regulatory databases to find all relevant federal and state agencies that …
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question 22 1 pts the half - life of an isotope is 1.4 years. if there …
100g
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question 8 energy is stored in food as the potential energy of the elec…
Approximately 0.14 glasses.
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this is a timed test. you will get to use your chemistry ref. tables, a…
True
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question 19 1 pts the following is an example of fusion. $_{85}^{216}at…
False
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when a chemical bond is broken, ______ is released. o energy o the cofa…
energy
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this is a timed test. you will get to use your chemistry ref. tables, a…
8
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where is chemical energy held within a molecule? ○ within the atomic nu…
Within chemical bonds
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which represent 2 different isotopes of the same element? a. carbon - 1…
C. Carbon - 13 & \(^{12}_{6}C\)
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fill in the blank question a series of chemical reactions called blank …
metabolic
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a balloon contains 5.42x10^23 atoms of argon gas. calculate the mass in…
B. 36.0 grams Ar
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perform the calculation. 25.0 psi × 175.6 k ÷ 87.8 k write your answer …
$50$ psi
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multiply the measurements. 0.789 g/ml × 27 ml write your answer with th…
21
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multiply the measurements. 0.789 g/ml × 27 ml write your answer with th…
21
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to \catalyze\ means to speed up. o true o false need help? review these…
True
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calculate the number of atoms in 2.31mol titanium. a 1.39x10^24 b. 3.84…
C. $1.39\times 10^{24}$
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aluminum selenide formula unit:______ rubidium fluoride formula unit:__…
Aluminum selenide: $Al_2Se_3$ Rubidium fluoride: RbF Sodium bromide: NaBr Strontium oxide: SrO Cesium phosphide: $Cs_3P$
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how may moles of magnesium are in 524g mg? a 21.6 moles mg b. 12738 mol…
A. 21.6 moles Mg
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multiply the measurements. 0.933 mol/l × 1.550 l write your answer with…
$1.45$
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multiple choice question what does the term catalyze mean? activate spe…
B. Speed up
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how many moles of copper contain 5.67×10²² atoms? a. 3.60×10³⁴ mols cu …
C. $9.42\times 10^{-2}$ moles Cu
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3.7 practice c - lewis structures of compounds name: becca g. part 1 - …
lithium nitride: Li₃N aluminum oxide: Al₂O₃ potassium phosphide: K₃P strontium chloride: SrCl₂ potassium sulfide: K₂S
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select all that apply which of these occur during a hydrolysis reaction…
A large molecule is broken down, A water molecule splits
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perform the calculation. 4,250 ml × 340.2 k ÷ 260.1 k write your answer…
5560 mL
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which type of catabolic reaction involves the addition of a water molec…
B. hydrolysis
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1. classify each of the following as a suspension, colloid, or solution…
a) Suspension. Explanation: Particles settle out and initially pass through filter. b) Colloid. Explanation: Small particles visible under microscope and scatters light. c) Colloi…
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fill in the blank question the figure, when read from left to right, re…
dehydration
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1. classify each of the following as a suspension, colloid, or solution…
a) Solution. Explanation: Passes through filter completely, indicating small - sized particles like in a solution. b) Suspension. Explanation: Small particles settle out over time…
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this is a timed test. you will get to use your chemistry ref. tables, a…
1. 56.4g/mol
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question 17 (5 points) why is open pit mining so devastating to the env…
D. It completely removes any available topsoil.
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which best describes what occurs in a dehydration reaction? a water mol…
A. A water molecule is removed from a molecule when it creates a covalent bond.
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module 1 test intro: (3 pts) regarding the atom, an electron displays a…
electron: Negative, proton: Positive, neutron: Neutral
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how does the hydroelectric dam pictured here impact the environment? a)…
A. By blocking fish migration
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the calculation of the density of a metal using water displacement. den…
## Part A - B. 11.2 g gold and 14.9 g gold - D. 15.2 g copper and 50.0 g copper ## Part B - Value: 6.1 - Units: g/mL
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during a dehydration synthesis reaction, a hydrogen atom is removed fro…
water
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part a study the picture of copper. how many connections or bonds does …
8
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directions: answer each question by circling the correct choice. after …
1. Blue 2. Yellow 3. Yellow - Green 4. Sky Blue 5. Red 6. Sky Blue 7. Purple 8. Sky Blue 9. Green 10. Red 11. Blue 12. Purple 13. Yellow - Green 14. Red 15. Sky Blue 16. Yellow - …
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part f which states of matter could your two models of water represent?
Liquid, solid (or liquid, gas)
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what type of absorbent was used to clean up the large chemical spill in…
Spill Pillows
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question 9 of 10 read the paragraph. then select the correct answer. at…
related to building
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multiple - choice question when diluting concentrated acid with water y…
Add acid to the water slowly while stirring
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part e water can exist in three different states of matter: solid, liqu…
Yes, this demonstration shows how the distance between water molecules can change. The molecules were more tightly - packed on one sheet of paper because the same number of molecu…
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question 1 what three conditions must be present for minerals to form t…
Question 1: Availability of elements, appropriate physical - chemical conditions, sufficient time for crystallization. Question 2: Metallic luster is like a metal's shine and refl…
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part c now build a model of liquid water. place your materials on a she…
Accurately representing the 3 - D structure and bond angles, and maintaining model stability.
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question 11 (3 points) properties of some solutions solution conductivi…
Solution 1
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part b are all the molecules in the picture the same? explain.
Without seeing the picture, it is impossible to determine if all the molecules in the picture are the same.
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nitrogen is mostly used to make...
Fertilizers
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what is wrong with the lewis dot formula shown? nitrogen has wrong numb…
Nitrogen has the wrong number of valence electrons.
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which of these elements is the most chemically reactive? a. germanium (…
D. Potassium (K)
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part a study the picture of liquid water at the molecular level. descri…
Oxygen and hydrogen atoms in water are connected by polar - covalent bonds within a molecule, and hydrogen bonds form between different water molecules.
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based on the periodic table of the elements, which of these elements ha…
C. barium (Ba)
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for all formula write the names to fill in the table or names given ide…
| Formula | Name | Ionic | Covalent | If Ionic - give the cation charge | | ---- | ---- | ---- | ---- | ---- | | $\text{Al}_{2}(\text{SO}_{4})_{3}$ | Aluminum sulfate | $\checkmar…
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which set of elements has the most similar physical and chemical proper…
C. K, Cs, Fr
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marcos and helen study the electron configurations of neutral atoms. th…
D. family
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which list of elements contains only metals? a. iodine, copper, argon b…
D. Tin, copper, cesium
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which of the following is unique for any given element? a. the mass of …
C. The number of protons
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the diagrams show part of the periodic table of the elements. the shade…
A. Option Text
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part e salt is both strong and brittle. these properties relate to its …
No, a toothpick is not a good model for showing the strength and brittleness of salt.
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which of the following describes how phosphorus cycles throughout earth…
Phosphorus is mostly found in ocean waters before cycling into a gaseous phase. (This statement is incorrect as phosphorus has a very limited gaseous phase in its cycle, making it…
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item 5 perform each calculation to the correct number of significant fi…
108.0
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for all formulas write the names to fill in the table or names given id…
| Formula | Name | Ionic Compound | Covalent Compound | If Ionic - Cation Charge | | ---- | ---- | ---- | ---- | ---- | | $(NH_4)SO_4$ | Ammonium sulfate | √ | | + 1 | | $O_2$ | O…
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question 7 (2 points) when a phase change is occurring (assume a pure s…
True
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what is wrong with the lewis dot formula shown?
The sulfur atom likely has an incorrect number of valence electrons shown and the atoms are not clearly labeled, making it difficult to assess the accuracy of the bonding and elec…
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true/false if you believe the statement to be more true than false, wri…
True/False: 1. F 2. F 3. F 4. T 5. F 6. F 7. F 8. F Fill - in - the - Blank: 1. Glucose 2. Epinephrine 3. sublingually 4. Side effects 5. liquid medications 6. drug
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question 5 (2 points) listen which of the following is a common acid? b…
B. Orange juice
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which strategies did the united states employ in order to achieve victo…
B. island - hopping D. bombing
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part c now build a model of salt. place your materials on a sheet of pa…
Possible difficulties could be maintaining the correct spatial arrangement of atoms, ensuring proper bonding representation with toothpicks, and keeping the model stable.
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question 4 (2 points) when a salt is formed as a result of an acid/base…
None of the above options are correct.
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question 4 (2 points) when a salt is formed as a result of an acid/base…
None of the above options are correct.
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distinguish between the absolute error and the relative error in a meas…
1. For large absolute error but small relative error: D. A company projects sales of $7.30 billion and true sales turn out to be $7.32 billion. 2. For small absolute error but lar…
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23 type the correct answer in the box a bathtub is filling with water a…
$29.3$
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match each molecular formula to the corresponding empirical formula. c₄…
$CH_3O$ → $C_4H_{12}O_4$ $CH_5O$ → $C_2H_{10}O_2$ $C_2H_4O$ → $C_4H_8O_2$
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given: 2al + 6hcl → 2alcl₃ + 3h₂. if the chemical reaction produces 129…
B. 2.92
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part b do the atoms in salt follow a pattern? explain your answer.
Yes, the atoms in salt follow a pattern. The sodium and chloride ions in sodium chloride form a cubic - crystal lattice structure where each sodium ion is surrounded by six chlori…
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select the correct answer. what is the percent composition of silicon i…
A. 28%
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type the correct answer in the box. express your answer to three signif…
311 K
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ch.- 16 state government fill in the blanks. 1. india has ______states …
1. 28, 8; Central or Union Government; 25; Question Hour; Governor 2. A. Member of Legislative Assembly; 30 years; 6 years; Ahmedabad; The power or authority to make legal decisio…
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9. practice: classification of matter question 1 how would you calculat…
Calculate using the formula $A = m_{107}\times a_{107}+m_{109}\times a_{109}$ with known isotope masses and abundances. ### Question 2
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question #5 - study these beakers...if the visible dots represent h+ io…
Solution A is likely an acid because it has the highest concentration of H+ ions as indicated by the largest number of visible dots representing H+ ions.
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part a study the picture of salt at the atomic level. describe the conn…
The sodium and chlorine atoms in salt are connected by ionic bonds. The electrostatic attraction between the positively charged sodium ions (Na⁺) and negatively charged chloride i…
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question 35 (2 points) listen which type of bond is responsible for hol…
D. covalent
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what type of form is the sculpture using? (david smith, cubi xix) selec…
B. geometric
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question #4 - is the color of the liquid being tested related to ph? be…
Yes, the color of the liquid being tested can be related to pH, especially when pH - sensitive indicators are used.
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question 31 (2 points) listen an acid is a compound that liberates ____…
D. $H^{+}$, decrease
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question 30 (2 points) listen which type of bond exists between water m…
E. hydrogen
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given: 4na + o₂ → 2na₂o. in this chemical reaction, how many moles of n…
1.45
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what is the mass of one mole of phosphorous (p) atoms? express your ans…
30.97
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select the correct answer. james needs 4.20 moles of nabr for an experi…
A. 425
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warm - ups 1) name a) 18f6 b) n2315 c) o2f2 2. write formulas for a) ca…
1. c) Dioxygen difluoride 2. a) $CCl_4$ b) $P_4Br_7$ c) $As_2S$ (assuming it's arsenic disulfide)
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select the correct answer. rachel has a sample containing 2 moles of ca…
A. $1.2044\times 10^{24}$ atoms
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which part of john daltons theory was disproved by j.j. thomsons cathod…
C. Atoms are indivisible.
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what is unique about how the periodic table of the elements is organize…
Elements with similar properties are grouped together in a pattern.
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a scuba divers air tank contains oxygen, helium, and nitrogen at a tota…
B. 103 atm
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question 35 (2 points) which of these represents the correct ordering o…
hydrogen, ionic, covalent
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question 33 (2 points) listen an acid is a compound that liberates ____…
C. $H^+$, decrease