化学
化学反应、化学计量、分子结构与元素性质。
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directions. the left - column gives an example of an object or situatio…
| Object / Situation | Initial form of Energy | Final form(s) of energy | | ---- | ---- | ---- | | 2. Cheetah Running | Chemical Energy | Mechanical (kinetic) and Thermal | | 3. L…
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question 15. when balancing the equation h3po4 + koh → k3po4 + h2o the …
3
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question 14 if a box of cacl₂ has a mass of 2.56 g. blank 1 moles are i…
Blank 1: 0.0231 Blank 2: 4.17 Blank 3: 22
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question 13 the molar mass of c₂h₄(nh₂)₂ is blank 1 g/mol. blank 1 add …
60
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question 12 blank 1×10^blank 2 atoms are found in a sample contains 2.5…
Blank 1: 2.04 Blank 2: 23
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question 22 what three elements are often found in organic compounds? a…
b. CHO
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timed test. this test has a time limit of 1 hour. this test will save a…
C. it can react with up to four other atoms to form covalent bonds
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question 18 water is a polar molecule because a. different parts of the…
A. different parts of the molecule have slightly different charges
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when 3.20 g of a nonelectrolyte solute is dissolved in water to make 76…
concentration: $0.0437\ M$ moles of solute: $0.0334\ mol$ molar mass: $95.8\ g/mol$
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a solution is made by dissolving 0.748 mol of nonelectrolyte solute in …
$T_f = 0.96\ ^{\circ}C$ $T_b = 82.35\ ^{\circ}C$
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a 50/50 blend of engine coolant and water (by volume) is usually used i…
$109.19^{\circ}C$
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4 which of the following molecules blocks harmful ultraviolet radiation…
Ozone
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timed test this test has a time limit of 1 hour.this test will save and…
True
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1 ozone is composed of _______. three oxygen atoms one oxygen atom and …
A. three oxygen atoms
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question 8 which atom(s) is chemically stable? 17: chlorine 2,8,7 10: n…
d. Ne
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biphenyl, $c_{12}h_{10}$, is a nonvolatile, nonionizing solute that is …
$78.65\ Torr$
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a solution of h₂so₄(aq) with a molal concentration of 5.25 m has a dens…
$4.4$
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what is the mole fraction of solute in a 3.67 m aqueous solution? $x_{s…
0.062
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calculate the molality of a solution formed by adding 9.40 g nh₄cl to 1…
$13.75\ m$
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the solubilities of three salts in water are shown in the graph. for ea…
$Pb(NO_3)_2$: 0 g KI: 0 g $K_2Cr_2O_7$: 100 g
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nonpolar molecules have a. only a positive pole b. no negative or posit…
B. no negative or positive poles
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question 2 which of the following statements most accurately describes …
C. Electrons are exchanged between atoms in ionic bonds, but they are shared between atoms held together by covalent bonds
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the solubilities of three salts in water are shown in the graph. for ea…
\(Pb(NO_3)_2\): 0 g \(KCl\): 100 g \(K_2Cr_2O_7\): 0 g
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bohrs atomic model differed from rutherfords because it explained that …
electrons exist in specified energy levels surrounding the nucleus.
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geber introduced the scientific method and experimentation in chemistry…
TRUE
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based on the article \will the real atomic model please stand up?\ desc…
According to Dalton's theory, a molecule of water is made up of atoms of hydrogen and oxygen combined in a specific whole - number ratio.
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q2. (6 points) name the following molecular compounds: a) b₂h₆ = b) h₂s…
a) Diborane b) Hydrogen selenide c) Phosphorus trichloride
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3 which part of the atom is responsible for the different mass numbers …
D. Nucleus
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the periods on the periodic table determine what energy level the outer…
11. The outermost electrons of iodine are in the n = 5 energy level. 12. Metals are located on the left - hand side and in the middle of the periodic table. 13. Non - metals are l…
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an exergonic reaction __________ energy. requires releases rewatch
releases
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configuration writing practice write a ground state electron configurat…
1. $1s^{2}2s^{2}2p^{6}3s^{1}$ 2. $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}4p^{6}5s^{2}4d^{10}5p^{6}6s^{2}4f^{14}5d^{10}6p^{2}$ 3. $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}4p…
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at 25 °c and 785 torr, carbon dioxide has a solubility of 0.0351 m in w…
$0.0783$
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multiple choice 1 point this type of society is seen when there is homo…
1. Xenocentrism 2. Mechanical solidarity
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the periods on the periodic table determine what energy level the outer…
11. The outermost electrons of iodine are in the $n = 5$ energy level. 12. Metals are located on the left - hand side and in the middle of the periodic table. 13. Nonmetals are lo…
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classify each of the events based on whether the solubility of the gas …
Gas solubility increases: The partial pressure of an anesthetic gas is increased, O₂ in the blood of a person who is placed in a hyperbaric chamber, The temperature is decreased G…
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a scientist is determining the mass of 33,000 molecules of oxygen. use …
$1.7\times 10^{-18}$ grams
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the density of hydrogen is 0.0000899 $\frac{g}{cm^{3}}$. which of the f…
B. $9\times 10^{-5}\ \frac{g}{cm^{3}}$
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a scientist is determining the mass of 33,000 molecules of oxygen. use …
2
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7. a saturated solution of caproic acid, hc₆h₁₁o₂, contains 11 g of the…
$K_a = 1.4\times10^{-5}$, $pK_a=4.85$
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the periodic table coloring activity the periodic table contains a lot …
1. Period: Horizontal row. Group: Vertical column. 2. a) Group 2, Period 4. b) Group 13, Period 3. c) Group 16, Period 2. d) Group 11, Period 6. 3. a) Metal. b) Non - metal. c) Me…
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nformation provided, fill in the blanks for 18 ar argon 39.95 protons: …
Neutrons: 22 Electrons: 18 Atomic Number: 18 Atomic Mass: 39.95
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protons: 3 neutrons: 4 electrons: 3 14 si silicon 28.09 protons: 14 neu…
Neutrons: 14 Electrons: 14
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t below, identify the amount of each subatomic particle. 3 li lithium 6…
For Lithium (Li): Protons: 3 Neutrons: 4 Electrons: 3 For Oxygen (O): Protons: 8 Neutrons: 8 Electrons: 8
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question 8 when balancing the equation 2h2 + o2 → 2h2o, what is the rat…
B. 2:1
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question 6 if 0.5 moles of nacl are present, how many grams does it wei…
C. 29.22 grams
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part 4: fill in the blanks 1. a substance that cannot be broken down in…
1. Element 2. Heterogeneous mixture 3. Homogeneous mixture 4. Distillation 5. Dull
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how do you convert grams of a substance to moles? a divide the mass by …
A. Divide the mass by the molar mass.
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question 3 what is the approximate number of particles in one mole of a…
E. $6.022\times 10^{23}$
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question 3 match the following terms with their definitions. prompts 1)…
1. The amount of substance containing Avogadro's number of particles. 2. The mass of one mole of a substance, usually expressed in grams. 3. The calculation of reactants and produ…
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question 1 what are the structural and functional differences between s…
Structurally, simple carbohydrates are made of one or two sugar units while complex carbohydrates are long - chains of sugar units. Functionally, simple carbohydrates provide quic…
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some substances, like chocolate or candle wax, can change from a solid …
This happens due to the change in intermolecular forces with temperature. Heating weakens them causing melting (solid - to - liquid), and cooling strengthens them causing solidifi…
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1. all of the things around you are called 2. if you keep cutting an ob…
1. matter 2. atom 3. indivisible 4. empty space 5. nucleus; protons; neutrons 6. positive 7. no 8. electrons 9. matter 10. extremely small 11. T 12. atoms; molecules 13. H₂O 14. 2…
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question 19 using the equation 2li + 2h₂o → 2lioh + h₂ when 2.5 g of li…
Question 19: 93.4% Question 20: 1.12
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part 3: match the term to the correct description. 1. homogeneous mixtu…
1. Homogeneous mixture - A mixture in which the components are uniformly distributed. 2. Element - A substance made up of only one kind of atom. 3. Compound - A substance made up …
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what is the mass of a sample of ethanol that exactly fills a 200.0 ml c…
$157.8\ g$
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question 17 using the equation 2c6h11 + 15o2 → 12co2+ 22h2o, blank 1 gr…
1478.4 ### Question 18
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at 1 atm, how much energy is required to heat 79.0 g h₂o(s) at -10.0 °c…
$246\ kJ$
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9. a reaction will never be spontaneous when a) $delta g^{circ}>0$. b) …
e) $\Delta G>0$
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a block of aluminum occupies a volume of 15.0 cubic cm and has a mass o…
2.7 g/cm³
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question 15 when balancing the equation h3po4 + koh → k3po4 + h2o the c…
3 ### Question 16
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calculate the heat energy released when 26.0 g of liquid mercury at 25.…
$0.530$
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question 10 of 17 how much heat energy is required to boil 70.2 g of am…
96.4 kJ
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question 13 the molar mass of c₂h₄(nh₂)₃ is blank 1 g/mol. blank 1 add …
Blank 1 (for \(C_2H_4(NH_2)_3\) molar mass): \(76.15\) Blank 1 (for \(CaCl_2\) moles): \(0.0231\) Blank 2 (for \(CaCl_2\) atoms coefficient): \(4.17\) Blank 3 (for \(CaCl_2\) atom…
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jaime is watching your favorite television program and sees a commercia…
norepinephrine
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directions: answer each question by circling the correct choice. after …
1. Blue 2. Yellow 3. Yellow - Green 4. Orange 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 - Gr…
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question 11 blank 1 mols of mg are equal to 2.58x10^26 atoms of mg. bla…
Question 11: 428 Question 12: Blank 1: 2.04 Blank 2: 23
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part 3: match the term to the correct description. 1. homogeneous mixtu…
1. No match 2. b. A substance made up of only one kind of atom. 3. a. A substance made up of two or more elements combined in a definite proportion. 4. c. A mixture in which the c…
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question 10 when balancing the equation 2h2 + o2 → 2h2o, what is the ra…
B. 2:1
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question 8 oxygen diatomic o2 is a form of elemental oxygen. question 9…
Question 8: True Question 9: molar mass
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#4 how do you find the atomic mass of an atom? a) add the total number …
C. Find the sum of protons and neutrons in an atom
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question 8 oxygen diatomic is a form of elemental oxygen. question 9 in…
O2
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is freezing juice a physical or chemical change? chemical change physic…
Physical Change
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if 0.5 moles of nacl are present, how many grams does it weigh? (molar …
C. 29.22 grams
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250 bonus 87% 14/15 fireworks chemical change physical change
Chemical Change
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a physical change... creates a new substance and cannot be undone. chan…
The correct option is: changes the physical properties of an object, but does not create a new substance.
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question 6 what is the term for the reactant that is completely consume…
A. Limiting reactant
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water freezing into ice is an example of a... chemical change physical …
Physical Change
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what is the approximate number of particles in one mole of any substanc…
E. $6.022\times 10^{23}$
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does this picture show a chemical or physical change? physical chemical
B. chemical
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is this an example of a physical or chemical change? physical because i…
Physical because it is a mixture.
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physical or chemical change? making a paper airplane. physical change c…
Physical Change
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how do you convert grams of a substance to moles? a divide the mass by …
A. Divide the mass by the molar mass.
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which of the following is not an example of chemical change? sour milk …
D. breaking a pencil
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wood that is burning in a brush pile has heat, and produces ashes. wood…
Chemical
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a chemical change creates a new substance and cannot be undone. changes…
creates a new substance and cannot be undone.
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which is not a physical change? cutting a pizza into equal slices. a ch…
Baking cupcakes.
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question 4 match the following terms with their definitions. prompts 1 …
1. The amount of substance containing Avogadro's number of particles. 2. The mass of one mole of a substance, usually expressed in grams. 3. The calculation of reactants and produ…
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chemical or physical? glass breaking into tiny shards
Physical Change
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which of these example is a physical change?
Broken Pencil
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question 2 to yield theoretical with reactants and products is used for…
stoichiometry
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fill in the blank use the vocabulary words from the vocabulary matching…
atom; subatomic particles; nucleus; protons; neutrons; protons; neutrons; electrons; atomic mass
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what happened to change the state of the butter? more heat was added. m…
A. More heat was added.
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is milk going sour a physical or chemical change? physical chemical
Chemical
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question 1 a balanced chemical equation has the same number of each typ…
A. True
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the energy required to initiate a reaction is called a activation energ…
A. Activation energy
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complete and balance the molecular equation for the reaction of aqueous…
Molecular equation: $2NH_4Br(aq)+Pb(C_2H_3O_2)_2(aq) ightarrow PbBr_2(s)+2NH_4C_2H_3O_2(aq)$ Net - ionic equation: $2Br^-(aq)+Pb^{2 + }(aq) ightarrow PbBr_2(s)$
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fill in the blank use the vocabulary words from the vocabulary matching…
1. atom 2. subatomic particles 3. nucleus 4. protons 5. neutrons 6. protons 7. neutrons 8. electrons 9. atomic mass
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chemical reactions a absorb more energy than they release b can either …
1. B. can either release more energy than they absorb or absorb more energy than they release, depending on the reaction 2. D. The yellow substance is a solid at room temperature
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question 1 (1 point) shape is a chemical property true false question 2…
- Question 1: False - Question 2: d. physical property - Question 3: True
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reading a graduated cylinder maughan howell multiple - choice question …
30.0 mL