化学
化学反应、化学计量、分子结构与元素性质。
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structure of poetry quick check do not go gentle into that good night b…
abaa ba
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insert dashes where needed. at sunfest organic farm a cutting - edge he…
At Sunfest Organic Farm—a cutting - edge herb farm in Okeechobee, Florida—the herbs are washed with ultraviolet light in a vacuum - sealed room.
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a compound with the molar mass 180 g/mol has an empirical formula of ch…
\(C_6H_{12}O_6\)
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what is the empirical formula for a compound containing 38.8% carbon, 1…
A. \(CH_{5}N\)
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a compound is analyzed as 32.0% c, 42.6% o, 18.7% n, and 6.7% h. what i…
\(C_{2}H_{5}O_{2}N\)
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a compound has the empirical formula given below. c7h5o2 which compound…
\(C_{14}H_{10}O_{4}\)
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what is the empirical formula of this compound? na₂s₂o₈ naso₄ na₂so₄ na…
\(NaSO_4\)
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carbon - 12 and carbon - 13 are isotopes of carbon. which of the follow…
They both have the same atomic number.
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a sample of h₂so₄ is found to contain 1.05 g of h, 16.67 g of s, and 33…
\(65.25\%\)
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the table below gives the numbers of protons, electrons, and neutrons i…
3
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a sample of hno3 contains 1.01 g of h, 14.01 g of n, and 48.00 g of o. …
\(22.23\)
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a particle that travels around the nucleus of an atom in orbitals is ca…
electron.
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what is the mass of 2.40 x 10^{24} molecules of c_{3}h_{8}? (1 mole c_{…
\(176\) g
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what is the mass of 3.01 x 10^{23} molecules of c_{6}h_{12}o_{6}? (1 mo…
\(90.09\)
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which element has 16 protons in its nucleus? neon oxygen sodium sulfur
sulfur
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what is the mass of 6.80 moles h₂o? molar mass h₂o = 18.02 g/mol ? g h₂o
\(122.54\space g\) (rounded to four significant figures as the least number of significant figures in the given values \(6.80\) (three) and \(18.02\) (four) is three, but \(6.80\)…
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which two particles are found in the nucleus of an atom? neutrons and e…
protons and neutrons
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what is the mass of 6.80 moles h₂o? molar mass h₂o = 18.02 g/mol ? g h₂o
\(122.54\space g\) (rounded to four significant figures as \(6.80\) has three significant figures and \(18.02\) has four, and the rule for multiplication is to go with the least n…
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a neural ____________ or, chemical messenger, travels across the synaps…
A. transmitter...receptor
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a lithium atom has three protons, three neutrons, and three electrons. …
B. \(0\)
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how many moles of al₂s₃ are equivalent to 605 g al₂s₃? molar mass al₂s₃…
$4.03$
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what is the molar mass of this compound? xef₄ remember to round to the …
207.30 g/mol
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what is the molar mass of this compound? ca(oh)₂ remember to round to t…
\(74.10\ g/mol\)
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there are 2 moles of k in one mole of k₂co₃. how many atoms of k are pr…
\(1.20\times 10^{24}\space\text{atoms}\) (the second option)
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an atom contains one proton, one electron, and one neutron. which two p…
the proton and the neutron
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how many potassium atoms are present in one formula unit of potassium c…
2 atoms
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how many carbon atoms are present in one mole of serotonin? c₁₀h₁₂n₂o 6…
\(6.02\times 10^{24}\) atoms
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1. what kind of bond am i? use the type of elements present to determin…
Covalent ## b.
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how many carbon atoms are present in one molecule of serotonin? c₁₀h₁₂n…
10 atoms
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how many grams are in 6.02 x 10^{24} molecules of hydrogen, h_2? molar …
\(20.2\text{ g H}_2\)
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an atom of element be has four protons, four electrons, and five neutro…
beryllium - 10
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what is the mass of 2.5 x 10^24 atoms of ne? molar mass of ne = 20.18 g…
\(84\space g\space Ne\)
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how many moles of cu are present in 1.51 x 10^{22} atoms cu? 2.51 x 10^…
0.0251 moles Cu
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how many atoms of na are present in 1.15 moles of sodium? 6.02 x 10^{24…
\(6.92\times 10^{23}\text{ atoms Na}\) (the second option)
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a compound has the empirical formula given below. c7h5o2 which compound…
\(C_{14}H_{10}O_{4}\)
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a 50.0 g sample of an unknown compound contains 14.19 g na, 19.76 g o, …
$28.38\%$
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bleach is used to clean, sterilize, and whiten when exposed to sunlight…
$47.62$
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how many molecules of methane, ch4, are in 125 g ch4? (1 mol ch4 = 16.0…
Coefficient (green box): \(4.7\), Exponent (yellow box): \(24\)
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how many molecules of sf6 are in 25.0 g sf6? (1 mol sf6 = 146.06 g) (1 …
Coefficient (green): \( 1.03 \) Exponent (yellow): \( 23 \)
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what is the mass of 4.54 moles of na₂so₄? molar mass na₂so₄ = 142.04 g/…
\(644.86\space g\) (rounded to two decimal places)
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for each reaction, write the chemical formulae of the oxidized reactant…
- \(2Fe(s)+3CuCl_{2}(aq)\to2FeCl_{3}(aq)+3Cu(s)\): reactants oxidized: \(Fe\); reactants reduced: \(CuCl_{2}\) - \(Pb(s)+Hg(NO_{3})_{2}(aq)\to Hg(l)+Pb(NO_{3})_{2}(aq)\): reactant…
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for each reaction, write the chemical formulae of the oxidized reactant…
- For \(FeI_2(aq)+Mg(s)\to MgI_2(aq)+Fe(s)\): - reactants oxidized: \(Mg\) - reactants reduced: \(FeI_2\) - For \(CuCl_2(aq)+Mg(s)\to MgCl_2(aq)+Cu(s)\): - reactants oxidized: \(M…
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decide whether each chemical reaction in the table below is an oxidatio…
- For \(CuSO_{4}(aq)+Zn(s)\to ZnSO_{4}(aq)+Cu(s)\): redox reaction? yes; reducing agent: \(Zn\); oxidizing agent: \(CuSO_{4}\) - For \(HCl(aq)+NH_{3}(aq)\to NH_{4}Cl(aq)\): redox …
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decide whether each chemical reaction in the table below is an oxidatio…
For \(2Cl_{2}(g)+Sn(s)\to SnCl_{4}(s)\): - redox reaction? yes - reducing agent: \(Sn\) - oxidizing agent: \(Cl_{2}\) For \(CO_{2}(g)+2H_{2}O(l)\to H_{3}O^{+}(aq)+HCO_{3}^{-}(aq)\…
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periodic trends - ionization energy practice for each of the following …
1. Ge 2. Cl 3. F 4. He 5. \(Li\lt H\lt Be\) 6. \(In\lt B\lt I\) 7. \(Sr\lt Sn\lt Au\) 8. \(Sg\lt Mg\lt Pd\) 9. \(Na\lt O\lt Kr\) 10. \(Ti\lt Co\lt C\) 11. \(Rf\lt Se\lt Ne\)
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which statement is true about metals? they are poor conductors. they ar…
They are excellent conductors.
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for each of the following grouping of elements, circle the element with…
1. Ge 2. Cl 3. F 4. He 5. Li < H < Be 6. In < B < I 7. Sr < Au < Sn 8. Sg < Mg < Pd 9. Na < O < Kr 10. Ti < Co < C 11. Rf < Se < Ne
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match each human condition with the system or chemical that has failed …
- Diarrhea - digestive system - Low blood oxygen - respiratory system - Hypothermia - nervous system
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classify each chemical compound listed in the table below. compound typ…
| compound | ionic | molecular | acid | base | | ---- | ---- | ---- | ---- | ---- | | \(HF\) | | \(\square\) | \(\square\) | | | \(H_{2}SO_{4}\) | | \(\square\) | \(\square\) | | …
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classify each chemical compound listed in the table below. compound typ…
| compound | ionic | molecular | acid | base | |--|--|--|--|--| | \(NaNO_3\) | \(\checkmark\) | | | | | \(H_2SO_3\) | | \(\checkmark\) | \(\checkmark\) | | | \(H_2SO_4\) | | \(\ch…
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periodic table of elements it represents an element that will readily a…
- It represents an element that will readily accept an electron. - It represents an element that is from the halogen group.
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periodic table of elements which elements have metallic bonds at room t…
potassium, cesium
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which of the following are true for the compound cacl₂? select two corr…
- Its name is calcium chloride. - It forms an ionic bond.
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periodic table of elements which of the following are true for the comp…
- Its name is calcium chloride. - It forms an ionic bond.
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when elements from group a combine with elements from group c, these co…
ionic salts
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2. what is the name for the compound na₃(po₄)? sodium phosphite sodium …
Sodium phosphate
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they checked the density of these materials without changing them. ther…
physical
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the sodium reacted with the water (explosively!). reactivity changed th…
chemical
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they tested magnetism without changing the material (there were no chem…
A. physical
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completa la siguiente oración. a partir de los diagramas de lewis, pued…
A partir de los diagramas de Lewis, puedo deducir que los átomos formarán enlaces iónicos cuando **transfieren** electrones, y enlaces covalentes cuando **comparten** electrones.
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what is not one of the 3 primary types of matter? (there are actually m…
love
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decide si cada par forma un enlace iónico o covalente. a. flúor (f) + f…
# Explicación breve: - **A. Flúor (F) + Flúor (F) (\(F_2\))**: - Los átomos de flúor comparten electrones ya que son no metales y se unen para alcanzar la estabilidad electrónica.…
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what does the word \clink\ in line 5 suggest about the poems subject? a…
B. A villanelle has a pleasing and delicate sound
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multiple - choice question what is matter? something that can be touche…
Anything that has weight and takes up space.
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the diagram represents the electron dot formula for the bonding of mg a…
- The two elements join together in an ionic bond. - The two electrons that the \(Mg\) atom loses are gained by the chlorine atom.
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how does the structure of this sonnet most clearly affect its meaning a…
Its regular pattern of rhythm, or meter, reflects the progression of one season to the next.
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is water symmetrical or assymmetrical? symmetrical assymmetrical
Assymmetrical
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is water polar or non - polar
Polar
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which 2 variables are directly proportional according to gay lussacs la…
Temperature and Pressure.
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calculate the volume that a 0.323 - mol sample of a gas will occupy at …
\(7.81\ L\)
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which is the correct lewis dot structure for the compound lithium nitri…
D
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answer each question. please note: you can answer each question only on…
By adding or extracting electrons.
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question 10 identify the number of valence electrons of selenium 2 6 8 …
6 # Question 11
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question 8 what is used to represent a bond in a covalent compound? o a…
Question 8: Lines are used to represent a bond in a covalent compound. Question 9: There are 2 electrons in a single bond.
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10,000 pts cations have no dots because they have donated their electro…
True
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question 2 the cation in an ionic lewis dot structure should not have a…
- Question 2: A. True - Question 3: A. True
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question 2 10,000 pts the cation in an ionic lewis dot structure should…
True
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multiple - choice question monomers are like building blocks constructi…
A. Building Blocks
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compounds that are solids, liquids or gasses at room temperature are?
Covalent
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compounds that are only found in solid state are? covalent ionic
Ionic
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which one of these would be a gas at room temperature? koh nacl mgcl₂ s…
\(SO_{2}\)
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which one of these would have a high melting point? nacl nh₃ so₂ co₂
NaCl
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use the chemical equation and the table to answer the question. pb(no₃)…
\(853.5\space g\)
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calculating mass quick check use the chemical equation to answer the qu…
19.5 g
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calculating mass quick check use the chemical equation to answer the qu…
\(2(108\space g/mol)+32\space g/mol = 248\space g/mol\), \((248\space g/mol)(0.02\space mol)=4.96\space g\)
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calculating mass quick check a student knows the mass of one of the rea…
Divide the mass of the reactant by its molar mass to find the number of moles of the reactant. Use the chemical equation to find the number of moles of the product. Multiply the n…
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calculating mass quick check which option correctly describes the react…
The mass of the reactants must be equal to the mass of the products. The total number of moles of the reactants can be more or less than the total number of moles of the products.
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in order to understand the periodic trend of atomic radius across a row…
| | Na | Al | P | Cl | Ar | |---|---|---|---|---|---| | Electron configuration | \(1s^{2}2s^{2}2p^{6}3s^{1}\) | \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{1}\) | \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{…
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structure of poetry quick check what is the aesthetic impact of a poem?…
how the poem affects the reader's senses
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structure of poetry quick check use the lines to answer the question. w…
ABAB
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the townsville blood bank is desperately in need of blood donors. which…
Adam, who has just fallen head - over - heels in love.
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which statements describe the image? check all that apply. the wood is …
- The process works only with organic matter. - The element has a half - life of 5,730 years.
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a. nomenclature and structure 1. identify the compound names of the fol…
a. Ethanethiol b. 2 - methylpropanethiol c. Diethyl sulfide d. Dimethyl sulfide
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an organic acid is composed of carbon (54.52%), hydrogen (9.17%), and o…
\(C_{4}H_{8}O_{2}\)
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a compound is found to contain 79.89% c and 20.11% h by mass. determine…
mol C: \(6.65\), mol H: \(19.95\)
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an alcohol is 68.84% c and 4.962% h by mass. the rest is oxygen. what i…
\(C_{7}H_{6}O_{2}\)
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vitamin c has the formula c h o. you burn 0.0400 g of the compound in a…
\(0.00136\space mol\)
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a 9.545 gram sample of an organic compound containing only c, h, and o …
empirical formula = \(C_2H_4O\) molecular formula = \(C_4H_8O_2\)
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a standard solution is prepared for the analysis of fluoxymesterone (c₂…
\(5.4\times 10^{-8}\space M\)
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a gas is heated in a sealed container. the volume of the container does…
D. The average kinetic energy of the particles increases.