化学
化学反応、化学量論、分子構造、元素の性質。
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question 35 of 38 which of the following is an example of a pure substa…
salt
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question 34 of 38 what type of chemical reaction requires the absorptio…
B. endothermic
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question 33 of 38 the location you use for mixing chemicals must be ___…
well ventilated
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which periodic trend is a measure of the tendency of an atom to attract…
A. electronegativity
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compared to the size of a sodium atom, a magnesium atom would have a sm…
a smaller atomic radius
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which is not a \green\ option in the chemical industry? supercritical c…
Using the least expensive organic solvent
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all of the following trends increase as shielding increases except- ato…
D. ionization energy
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which of the following statements is true about ions? cations form when…
B. cations form when an atom loses electrons
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which of the following statements correctly compares the relative size …
the radius of an anion is greater than the radius of its neutral atom
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which of the following elements has the smallest first ionization energ…
rubidium
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which of these elements has the lowest electronegativity values? cesium…
cesium
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which substance is a vapor at room temperature and standard atmospheric…
C. gasoline
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which is a chemical property of copper? a) reacts in air to form a gree…
A. reacts in air to form a green layer
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which of the following elements has the smallest atomic radius? sulfur,…
chlorine, Cl
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which of the following elements is in the same period as bromine? chlor…
calcium
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which group of the periodic table has 7 valence electrons? alkaline ear…
C. Halogens
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microwave mysteries fill - in - the - blank select the correct term fro…
1. watt 2. exciting 3. E. coli 4. atomic motion 5. smart buttons 6. safety circuits 7. magnetron tube 8. half 9. decrease 10. arcing
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what is an example of an extensive property? a) mass b) density c) temp…
A. mass
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choose all of the elements found in a family (group) with s²np³\ electr…
B. N, D. P
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what is the maximum amount of electrons that can be found in a p sublev…
6 (corresponding to the second option in the multiple - choice list)
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q1 chemistry: u2l8 mastery quiz 1 practice mad minute annotating mass s…
Peak with greatest number of neutrons: The peak at m/z = 98 Peak with greatest percent abundance: The peak at m/z = 90 How many isotopes are present: 5 Identity of the element: C.…
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across a row in the periodic table, as the atomic number increases, the…
decreases
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examine the mass spectrum of silicon below. mass spectrum of silicon (q…
1. B. Each isotope has the same atomic number but different numbers of neutrons. 2. Approximately 28.0855 u 3. B. The ion has 3 more electrons than neutrons.
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q1 chemistry: u2l8 mastery quiz 1 practice do now: use the data table b…
1. A. Atom A, B. Atom B 2. D. Atom D 3. B. Nitrogen - 18 4. (A) Atomic number = 6 (B) Mass number = 12 (C) Number of neutrons = 6
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10. **write the complete symbol for an atom with the following characte…
The atomic mass of the element is 121.76 amu and the element is antimony (Sb). #### b. For isotope 1: Nuclear symbol: \(\ce{_{51}^{121}Sb}\) (since \(Z = 51\) for antimony and \(A…
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2. *examine the diagram on the right and calculate... a. number of elec…
2. a. 4 b. 4 c. 3 3. a. Beryllium - 7 4. a. Atom A and Atom C 5. a. Atom A 6. d. Atom D 7. b. Atom B, c. Atom C 8. a. Atom A, b. Atom B * d. 40
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the above is an example of energy transformation energy being transferr…
D. all of these are correct
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1. use the data table below to answer the following questions. the two …
a. To create the mass spectrum: On the x - axis, label "Mass number" and mark 63 and 65. On the y - axis, label "Percent Abundance". Draw a peak at mass number 63 with a relative …
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2. write a skeleton and a balanced chemical equation for each chemical …
a) Skeleton: $Ca + KCl ightarrow CaCl_2+K$; Balanced: $Ca + 2KCl ightarrow CaCl_2+2K$ b) Skeleton: $MgCl_2 + NaNO_3 ightarrow Mg(NO_3)_2+NaCl$; Balanced: $MgCl_2 + 2NaNO_3 ightarr…
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about 99% of earths atmosphere consists of n₂ (nitrogen molecules) and …
- There is no difference in how well $O_2$ and $N_2$ dissolve, and both dissolve poorly in water. - Like all atoms, Ar has no charge or partial charge so dissolves poorly in water…
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the structure on the right in the figure below forms a part of many pro…
B. The structure on the left will dissolve in water, due to the polar OH and C = O groups. D. The structure on the left is an acid.
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science grade 10 assignment 2 - chemical reactions name: appl. /22 1. b…
a) Balanced equation: $3Pb(NO_3)_2+Al_2(SO_4)_3 = 3PbSO_4+2Al(NO_3)_3$, type: double - displacement b) Balanced equation: $2Br_2 + 3O_2=2Br_2O_3$, type: synthesis c) Balanced equa…
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question 49 which of the atoms listed below has the smallest radius? a …
B. P
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a chemist has 200 ml of a 10% sucrose solution. she adds x ml of a 40% …
400
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question 1 0.5 pts fdr began his presidency: with a badly - delivered a…
Prioritizing relief and recovery, then long - term reform
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which is an example of logos in \top of the food chain\? a. the people …
C. The chemical, which, by the way, cut down the number of mosquitoes exponentially, had the unfortunate side effect of killing off this little wasp... that preyed on a type of ca…
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in the equation 2h₂ + 1o₂ →→ 2h₂o if you change the 2h₂ to 3h₂ molecule…
It is not possible to produce water without leftover molecules.
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it takes 1 molecule of nitrogen and 3 molecules of hydrogen to produce …
$2N_2$ and $6H_2$
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you have 1,312 grams of a radioactive kind of lanthanum. if its half - …
164 grams
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balance of atoms question: which statement correctly explains why the a…
Some of the atoms in the paper became gases.
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one molecule of calcium oxide, cao, and one molecule of carbon dioxide,…
A. \(CaCO_{3}\)
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when iron rusts and forms iron oxide, the iron oxide has more mass than…
Iron oxide has oxygen atoms, and pure iron does not.
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scientific discoveries are often built on the previous findings of othe…
A. Atoms contain negatively charged particles, C. The electron has a specific mass
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17 the density of ethyl alcohol is 0.789 g/ml. what is the weight of et…
A. 158.0 g
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4.3 atomic structure 14. experiments by j.j. thomson showed that atoms …
14. Electrons; Plum - Pudding 15. Alpha; Nucleus; Protons; Neutrons 16. - 1; 1839; Neutron 17. (Sketching of Bohr's model involves circular orbits of electrons around a central nu…
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6. what plan do the rioters conjure to safely retain their discovery? h…
6. Two rioters guard the gold while one fetches food. 7. The Devil is thought to stoke their greed and evil intentions, influencing their betrayal plots. 8. All the rioters die du…
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15 a flask weighs 345.8 g. with 225 ml of carbon tetrachloride, it weig…
B. 1.59 g/mL
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4.3 atomic structure 14. experiments by j.j. thomson showed that atoms …
15. Alpha; proton; neutron 16. - 1; 1836; Neutron 18. Mass; protons; Chemical symbol of the element (Note: Sketch - related parts cannot be provided in this text - based format. F…
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you have been asked to write an essay about the effects of large amount…
Thesis statement: Americans consume large amounts of sugar in their daily diets, which leads to a variety of health problems. Supporting details: - The average American eats or dr…
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compounds consist of atoms are not created or destroyed in a chemical r…
13a. symbol 13b. subscript; symbol 13c. not
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9 calculate the density of sulfuric acid if 35.4 ml of it weighs 65.14 …
B. 1.84 g/mL
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8 28.5 g of iron shot raises the water level from 45.50 ml to 49.10 ml.…
C. 7.92 g/mL
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7 a block of lead has dimensions of 4.50 cm by 5.20 cm by 6.00 cm and w…
D. $11.32\ g/cm^{3}$
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a block of aluminum occupies a volume of 15.0 ml and weighs 40.5 g. wha…
C. 2.70 g/mL
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3 a graduated cylinder contains 22.5 ml of mercury weighing 306.0 g. ca…
B. 13.6 g/mL
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which sentence is an example of a concrete statement? a. i have both a …
A. I have both a BA and a master's degree in chemical engineering from Tate College in Connecticut.
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4.3 atomic structure 14. experiments by j.j. thomson showed that atoms …
14. electrons; Cathode - ray tube components: cathode, anode, fluorescent screen; Plum - pudding model components: uniform positive charge, electrons 15. alpha; nucleus; protons; …
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draw lewis structure for the following atoms potassium sulfer lodine al…
Potassium: K• Sulfur: :S•••• Iodine: :I•••• Aluminum: Al•••
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which type of energy is constantly replenished and sustainable? a. chem…
B. Renewable Energy
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which type of energy is constantly replenished and sustainable? a. chem…
B. Renewable Energy
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a) lewis/electron dot diagram b) show bond. ←←←look. do! c) chemical fo…
1. For Sodium and Oxygen: - a) Sodium (Na) has 1 valence electron and Oxygen (O) has 6 valence electrons. The Lewis - electron dot diagram for Na is Na with 1 dot and for O is O w…
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which of the following example demonstrates the reversibility of a chem…
recharging batteries
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which of the following happens during a chemical change but does not ha…
Atoms of one or more substances rearrange into a new substance.
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which of the following is a reliable way to observe that a chemical cha…
conduct a test to determine the chemical makeup of the molecules
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which of the following demonstrates a chemical change? (1 point) iron (…
iron (Fe) reacting to water(($H_2O$)) and oxygen(O) to form iron oxide($Fe_2O_3$)
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which of the following is an example of only a physical change? (1 poin…
dry ice becoming vapor
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which of the following is an example of only a physical change? (1 poin…
dry ice becoming vapor
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use pages 106 - 121 to find the answers to fill in the blanks: 4.1 the …
1. 118 2. atoms 3. 98%; oxygen, silicon, aluminum, iron, calcium, sodium, potassium, magnesium, hydrogen 4. different; abundant 5. oxygen, carbon, hydrogen, nitrogen, calcium, pho…
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4. which of these facts is supporting evidence that the universe is exp…
The galaxies are moving away from each other.
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the atomic mass of magnesium from the periodic table is 24.31 amu. what…
C. the weighted average of all of the naturally occurring isotopes of magnesium
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rubidium has two common isotopes $^{85}rb$ and $^{87}rb$. if the abunda…
$85.556$ amu
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li-6 has an atomic mass of 6.015 amu and a relative abundance of 7.5% w…
A. 6.94 amu
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8. the exact placement of the atomic number can vary between periodic t…
Upper left
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chromium has the following isotopic masses and % abundances: 49.9 amu 4…
$52.05$
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which of these facts is supporting evidence that the universe is expand…
The galaxies are moving away from each other.
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7. determine carbons atomic number
6
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question: which subatomic particle is responsible for the identity of a…
Protons
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dogs and cats __________ the majority of household pets. i need to see …
1. constitute 2. context 3. contract 4. create 5. data 6. define 7. derive 8. distribute 9. economy 10. environment
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nitrogen has two isotopes. one has an atomic mass of 14.003 amu and a r…
A. 14.007 amu
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calculate the atomic mass for carbon using the following data: mass num…
C. 12.011 amu
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iclicker: a process that is spontaneous in one direction is non - spont…
A. True
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atomic mass unit is calculated with reference to _____. a carbon b oxyg…
a. Carbon
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an isotope of what element is used as the standard for the atomic mass …
B. carbon
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academy ch 18 how electrotherapy and light therapy treat the skin case …
D. chemical exfoliant
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question 11. which of the following correctly describes the functions o…
Question 11: Nervous - Coordination of all body functions and senses; Endocrine - Produces chemical messengers called hormones Question 12: The head is superior to the liver in an…
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an isotope of what element is used as the standard for the atomic mass …
A. carbon
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___ is the reference standard for atomic mass units. a nitrogen - 11 b …
C. Carbon - 12
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what is the atomic mass of 1 atom of carbon - 12? a 12.011 g b 12 amu c…
B. 12 amu
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the atomic mass of helium - 4 is 4.0026 amu. how many of each particle …
D. 2 protons, 2 electrons, 2 neutrons
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38) in chemical reactions, electricity, a spark, and sunlight are all w…
38. C. activation energy 40. D. Decreasing the temperature 41. A. A sufficiently hard collision, C. A correctly oriented collision
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which instrument is used to measure the mass of atoms? (2 words)
Mass spectrometer
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35) in a chemical reaction, substances known as ________ will undergo c…
35. Reactants 36. True 37. False 38. D. Lowering activation energy
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the element which is used as a standard to measure the mass of one mole…
d. Carbon
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33) a 4.0 - liter container has two gases inside, neon and argon. it is…
33) A. 0.042 moles argon 34) A. 0.245 moles
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the element which is used as the base to calculate the atomic mass of a…
A. Carbon
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the introduction of a neutron into the nuclear composition of an atom w…
FALSE
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the isotope oxygen - 18 has an atomic number of 8. which of the followi…
A. 8 protons, 8 electrons, 10 neutrons
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19) the kinetic molecular theory describes the behavior of ____________…
19) Particles 20) True 21) D. All of the above 22) True
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the chemical properties of a given element are dictated by: a the numbe…
A. the number of protons and the number of electrons
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16) there are a variety of acids and bases. scientists would call anyth…
16. D. Strong acid 17. B. Strong base 18. False