化學
化學反應、化學計量、分子結構與元素性質。
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drag each label to the correct location on the image. identify the four…
- Reactants: The substances at the lower - left part of the graph with initial energy. - Activation energy: The vertical distance from the energy level of reactants to the peak of…
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multiple choice question misty begins her conclusion by saying, \my pur…
She relates to the audience by saying, "these benefits extend not only to you but also to the environment."
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which statement best describes the rhyme scheme of \a thought on the in…
There are two stanzas with the rhyme scheme ABAB throughout.
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the passage below describes an experiment. sophie had medicine tablets …
Do whole tablets fizz for a longer period of time than crushed tablets?
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water molecules are also attracted to other kinds of molecules. this is…
A concave meniscus forms in a glass column when adhesive forces between water and glass are stronger than cohesive forces between water molecules.
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6) draw the following lewis dot structures using the periodic table. (s…
The Lewis dot structure for Br has the symbol 'Br' with 7 dots around it, with 2 dots on one side and 1 dot on each of the other three sides.
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question 5 which gas law shows an indirect relationship? boyles law avo…
A. Boyle's Law
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you increase the temperature of a can that contains gas. what law would…
B. Gay - Lussac's Law
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2 the density of zinc is 7.1 grams per cubic centimeter. the table show…
Substance 3
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as you decrease the volume of a balloon, the pressure increases. what g…
C. Boyle's Law
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which law describes the relationship between volume and temperature for…
D. Charles' Law
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question 3 when monomers are linked together they form a ____________ a…
b. polymer
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what does dr. lanyon notice about the powders found in dr. jekylls draw…
The powders look rare and appear to be of the highest quality.
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substance,element 1 symbol; metal/nonmetal,element 2 symbol; metal/nonm…
| Substance | Element 1 Symbol; Metal/Nonmetal | Element 2 Symbol; Metal/Nonmetal | Ionic/Covalent | Chemical Name | |---|---|---|---|---| | $P_3O_6$ | $P$; Nonmetal | $O$; Nonmet…
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practice it! select the atom(s) are found in nucleic acids. phosphorus …
phosphorus (P), hydrogen (H), nitrogen (N), carbon (C)
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chemistry safety quiz 1. which piece of lab ware is the best tool for m…
# Explicaciones Breves: 1. El probeta graduated (d) es la mejor herramienta para medir 100 ml de agua ya que está diseñado para mediciones precisas de volúmenes. 2. Un extintor de…
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determine the location of the last significant place value by placing a…
1. 80\(\overline{4}\)0 2. 0.03\(\overline{0}\)0 3. 699.\(\overline{5}\) 4. 2.00\(\overline{0}\)×10² 5. 0.901\(\overline{0}\)0 6. 90,\(\overline{1}\)00 7. 4.\(\overline{7}\)×10⁻⁸ 8…
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atomic structure parts of an isotope and ion use the atomic symbol to f…
| Atomic Symbol | Atomic Number | Mass Number | # of Protons | # of Neutrons | # of Electrons | Isotope or Ion? | Ionic Charge | |---|---|---|---|---|---|---|---| | $_1^2H$ | 1 | …
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measurement can only be as accurate and precise as the instrument that …
1. 1 2. 2 3. 3 4. 4 5. 1 6. 4 7. 6 8. 1 9. 4 10. 5
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which pair of names is identical? dr. william h. schemerhorn dr. willia…
Ms. Julia P. Youngman Ms Julia P. Youngman
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which element has an atomic number of 75? technetium rhenium tungsten
B. Rhenium
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which element has 16 protons in its nucleus? sulfur arsenic selenium
Sulfur
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which element has 15 protons in its nucleus? phosphorus sulfur selenium
Phosphorus
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which element has an atomic number of 19? calcium potassium sodium
Potassium
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correct the one error. carlotta_valdes it took me three hour to finish …
It took me three hours to finish my chemistry homework last night.
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18. which describes an element? a. a mixture of different substances b.…
B. A pure substance made of one type of atom
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which element has an atomic number of 19? calcium potassium sodium
B. Potassium
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12. what determines the boiling point of a substance? a. the color of t…
C. The intermolecular forces between particles
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which element has 34 protons in its nucleus? phosphorus sulfur selenium
Selenium
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5.64×12.458 = 70.26312 how many sig figs should i round this answer to?…
3
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d. a solid changes to a gas 11. which is a characteristic of a colloid?…
b. Particles scatter light
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7. which type of mixture has particles that settle over time? a. soluti…
7. b. Suspension 8. d. Buoyancy 9. c. A pure substance made of different elements chemically combined 10. b. A solid changes to a liquid 11. b. Particles scatter light
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30 type your answer... zinc 65.39 atomic #: type your answer... atomic …
ATOMIC #: 30 ATOMIC MASS: 65.39 # OF PROTONS: 30 # OF NEUTRONS: 35 # OF ELECTRONS: 30
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9. which best describes a compound? a. a pure substance made of one typ…
c. A pure substance made of different elements chemically combined
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7. which type of mixture has particles that settle over time? a. soluti…
b. Suspension
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5 fill in the blank 1 point 8 o type your answer... 15.999 atomic #: ty…
ATOMIC #: 8 ATOMIC MASS: 15.999 # OF PROTONS: 8 # OF NEUTRONS: 8 # OF ELECTRONS: 8
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5 fill in the blank 1 point: 8 o type your answer... 15.999 atomic #: t…
ATOMIC #: 8 ATOMIC MASS: 15.999 # OF PROTONS: 8 # OF NEUTRONS: 8 # OF ELECTRONS: 8
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4 fill in the blank 1 point to calculate the number of neutrons in any …
protons
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3 fill in the 1 point the number of electrons in a neutral atom will be…
protons
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elements in the same group have similar chemical and physical propertie…
1. B. True 2. A. True
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fill in the blank 1 point omic mass is the average number of answer and…
protons, neutrons
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4. which of these is an example of a homogeneous mixture? a. pizza b. s…
B. Salt water
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5. what is the process called when a solid changes directly to a gas? a…
d. Sublimation
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which best describes an electron? the heaviest particle in an atom wher…
The part of an atom that is negatively charged
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how many electrons are in an uncharged atom? the same as the number of …
the same as the number of protons
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when does an atom have a neutral charge? when the number of protons is …
when the number of protons equals the number of electrons
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why is most of the space occupied by an atom empty space? because the e…
because the electrons orbit the nucleus much like the planets orbit the sun
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which of these is accurate about the amount of space an atom occupies? …
most of the space is empty
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which of these makes up most of the mass of an atom? protons + neutrons…
protons + neutrons
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a local business supplies firewood to its customers. this business peri…
$C_{6}H_{10}O_{5}+6O_{2} ightarrow6CO_{2}+5H_{2}O$
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choose the correct answer where are electrons located in an atom? outsi…
outside the nucleus
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which of these is found in the nucleus of an atom? electron protons + n…
protons + neutrons
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iron (fe) reacts with oxygen (o₂) in the air to form rust, fe(s) + o₂(g…
B. reactants
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15. the nucleus of isotope a of an element has a larger mass than isoto…
C. the same as ### 16.
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questions: 1. electrons located in the outermost shell of the electron …
1. En orbitales en la capa externa de la nube electrónica. 2. El neutrón. 3. Protones y neutrones. 4. En orbitales siguiendo reglas de mecánica cuántica.
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what are biogeochemical cycles responsible for? ensuring efficient recy…
ensuring efficient recycling in nature
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question 6 of 17 leading zeros are always significant. true false
False
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24. which of these facts is supporting evidence that the universe is ex…
The galaxies are moving away from each other.
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acidity changes after dry ice is added what happens to the acidity of s…
The pH of solution A decreases, and the pH of solution B decreases.
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particles atoms 0.02×10²³ 1 mol calculate the number of moles in 36 gra…
$2\ mol$
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choose the correct answer. why does water vapor condense at higher elev…
due to cooler temperatures
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when methane (ch₄) is burned in the presence of oxygen (o₂), which prod…
d. Carbon dioxide and water
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source: camlyn williams, \a natural label on food means next to nothing…
Yes, because it fails to use quotation marks and fails to cite the source.
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calculate the answer to the question and put that answer in the blank. …
**20.8 g/mL**
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which cannot be considered supported by modern understanding of the boh…
The electron orbits are easily distinguished from one another.
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granite and rhyolite are chemically the same but where they crystallize…
1. a. True 2. a. True 3. a. True 4. b. False 5. b. False 6. b. False 7. b. False 8. a. True
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when zinc is placed in a copper sulfate solution, zinc displaces to for…
copper
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when sodium chloride reacts with silver nitrate, sodium nitrate and sil…
chloride
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question 13 4 pts a tall glass graduated cylinder contains four separat…
II, I, IV, III
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the density of gold is 19.3 g/cm³. what is the volume of a 13 g gold nu…
$0.67\ cm^{3}$
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question 16 4 pts what is the mass of 225 ml of a liquid that has a den…
198 g
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the decomposition of water into hydrogen and oxygen gas is an example o…
decomposition
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question 18 4 pts a nugget of gold with a mass of 521 g is added to 50.…
19.3 g/mL
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question 19 4 pts which of the following is not an element? water tin g…
water
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which of the following is a heterogeneous mixture? noodle soup water te…
noodle soup
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question 21 which of the following is an example of a physical change? …
grinding coffee beans
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the formation of water from hydrogen and oxygen is an example of a reac…
synthesis
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question 23 when a solid is converted directly to a gas, the change of …
sublimation
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why do dark - colored objects absorb radiant energy faster than light -…
Dark surfaces have more energy - absorbing electrons.
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the chart lists four different kinds of atoms. different kinds of atoms…
They cannot be divided and still keep the properties of the element.
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which describes a feature of the physical changes of all substances? ca…
does not change the identity of a substance
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multiple - choice question electron orbitals are always in the shape of…
false
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1) calculate the number of grams of cucl₂·2h₂o needed to prepare 50 ml …
$1.28\ g$
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6. compare oxygen (o) to selenium (se), choose the most accurate statem…
C. Oxygen has a lower ionization energy because it has a greater shielding effect.
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5. which of these elements has the larger atomic radii and why? a. f is…
D. Cl is the largest because it has the least amount of shielding effect. (Note: This option seems to have an incorrect reasoning as Cl has more shielding effect due to more energ…
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1. someone is cooking bacon in your home kitchen, but you can smell it …
Bacon particles are moving from high concentration (in the kitchen) to low concentration (the rest of the house)
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chapter 1: lesson 3 periodic table: metal: ductility: malleability: non…
Periodic table: A tabular display of chemical elements arranged by atomic number, electron configuration, and recurring chemical properties. Metal: An element that is typically a …
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4. which of these elements has the larger atomic radii and why? a. calc…
A. Calcium has a larger atomic radius than bromine because the nucleus of calcium has a weaker pull on its electrons compared to the nucleus of bromine.
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which element is correctly labelled below? element a alkaline earth met…
C. element C
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107. a chemist determines the constant s for a particular solution. he …
C. When $p = 1$ and $t eq0$ (closest option is C where $p = 1$ is given, though $t = 0$ in C makes the formula undefined in a strict sense, but the numerator condition for zero f…
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2. examine the periodic table below and determine the correct answer. i…
We need more information about the positions of these elements in the periodic table to determine which statements are true. Without specific group and period information for elem…
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1. which statements about the development of the periodic table of elem…
1. False 2. True 3. False 4. True 5. True So the answer is C (2 and 4 are true)
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ch 09 hair type and texture quiz question 12 of 12 1 point what is a qu…
It may be fragile and prone to frizz.
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periodic trends quiz form b pd: 3rd name: cishna gaycta 1. which statem…
D) 1 and 2 are true
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question 11 of 12 what is a quality of wavy coarse hair? select the cor…
It is prone to tangles and dryness.
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properties of water crossword (version #1) across 2. process where wate…
Across 2: Evaporation Across 5: Surface - tension Across 7: Adhesion Across 8: Condensation Across 9: Hydrophilic Across 10: Solvent Down 1: Hydrogen - bond Down 3: Hydrophobic Do…
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question 10 of 12 1 point what is a quality of coily afro - texture hai…
It may be fragile and prone to frizz.
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name: cristina garcia pd: 5 1. which statements about the development o…
1. C 2. C 3. C
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silvers atomic symbol (or abbreviation) is \ag.\ why does its atomic sy…
Because it is named after its Latin name, not its English name.
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question 2 of 12 1 point what is a quality of curly coarse hair? select…
C. It is prone to tangles and dryness.