化学
化学反应、化学计量、分子结构与元素性质。
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question 5 which is the physical change? electrolysis of water cutting …
Cutting a piece of paper with scissors
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question 4 choose the chemical change from the following options flatte…
Generation of heat from the decomposition of methane
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question 4 arrange the following from lowest ionization energy to highe…
Ca, Br, Kr
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fill in the missing words a main group atom is the most stable when its…
1. valence 2. incomplete 3. share 4. lose
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question 3 choose the chemical from the following options folding cloth…
The browning of an exposed piece of apple
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question 2 choose the physical change slicing a watermelon burning a me…
Slicing a watermelon
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arrange the following by increasing atomic size. br, ca, kr
Kr, Br, Ca
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question 1 which of the following is a physical change? oxidation of ir…
Water boiling into water vapor
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# question 2 (10 pt). in a 6 - bit system, use sign/magnitude scheme, p…
The resulting sum is not zero in decimal. The binary representation of 7 is 000111, - 7 is 100111, their binary sum is 101110, and the decimal value of the sum is - 14.
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drag the tiles to the correct boxes to complete the pairs. not all tile…
A. sulfur dioxide B. condensation of chemicals in the atmosphere C. acid precipitation D. acidic water
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periodic table - scrambled sentences worksheet name: via zayas date: 9 …
1. Elements in the same group have the same number of outer electrons. 2. The atomic number is the number of protons in an atom. 3. Nonmetals are generally brittle and poor conduc…
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fill in the missing words a) bonds form between a metal and a nonmetal …
a) Ionic b) Ionic c) Covalent d) Covalent
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ionic compounds containing transition metals please complete the follow…
| Name of Ionic Compound | Formula of Ionic Compound | | ---- | ---- | | 1. Copper (II) sulfate | $CuSO_{4}$ | | 2. Copper (I) oxide | $Cu_{2}O$ | | 3. Chromium (III) cyanide | $C…
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dfsc 2316 : pre - quiz 50 points, due 11:59:59 pm, 09/14/2025 please su…
$101_2 = 5$ $01011_2=11$ $10111010_2 = 186$ $A2B_{16}=2603$ $123_8 = 83$ 7 in 6 - bit sign/magnitude: $000111$ - 7 in 6 - bit sign/magnitude: $100111$ Binary addition result: $101…
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an article reported on a long - term study of the effects of hurricanes…
$108.7$
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34. which of the following is a clue of a chemical change? a. iron chan…
34. c 35. d 36. d 37. c 38. b 39. d 40. a 41. a
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b. measurements for an unknown solution using a buret |solution # titra…
The percent difference between the densities of Trial #1 and Trial #2 is approximately $42.95\%$.
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revlon was founded in 1932 by charles revson, his brother joseph, and c…
1. Salon educator 2. Film/editorial nail technician 3. Medical nail technician (MNT)
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q.9. how many moles of k are there in 36.70 g of k? ans. given: 36.70 g…
0.9386 mol
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environmental science swt #2 1. sustainability is making sure that the …
1. a. True 2. a. environment 3. a. Space Exploration 4. None of the above (The Tragedy of the Commons is when individuals over - use a shared resource for their self - interest, d…
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directions: go to schoology and open up the big bang folder. use nasa’s…
The Big Bang is how astronomers explain the way the universe began. It is the idea that the universe began as just a single singularity then exploded and stretched to grow as larg…
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q.7. write the z, a, number of subatomic particles in the following: | …
| | Ca | Ca²⁺ | S | S²⁻ | |--|--|--|--|--| | Z | 20 | 20 | 16 | 16 | | A | 40 | 40 | 32 | 32 | | #Protons | 20 | 20 | 16 | 16 | | # Neutrons | 20 | 20 | 16 | 16 | | # Electrons | …
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what must differ between the atom of two different elements? o electron…
protons in the atom
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which components of the atom have a positive charge? neutrons protons e…
B. protons
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what is the smallest unit that makes up matter? o molecules o chemicals…
D. atoms
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complete the following table. |formula|lewis structure|polar? y/n|imfs|…
| Formula | Lewis Structure | Polar? Y/N | IMFs | | ---- | ---- | ---- | ---- | | PCl₃ | P with 3 single bonds to Cl and 1 lone - pair | Y | Dipole - dipole, London dispersion | |…
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which statement best describes the arrangement of electrons in an atom …
There are two electrons in the first energy level and seven electrons in the second energy level.
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which element has atoms with valence electrons in a higher energy level…
Cesium (Cs)
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engine coolant chemicals: are considered toxic and children or pets may…
True
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6. for each of the four molecules below, complete the following: a. dra…
Ethane: Non - polar; Carbon dioxide: Non - polar; Methanol: Polar; Water: Polar; Oxygen: Non - polar; Methylamine: Polar; Acetic acid: Polar
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helium is in group 18 of the periodic table. how is helium different fr…
Helium atoms have 2 valence electrons in the first energy level, while atoms of the other elements in the group have 8 valence electrons in the second (or higher) energy level.
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two representative elements, nitrogen and oxygen, are in the same perio…
They have valence electrons in the same energy level.
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how many valence electrons does each atom of arsenic (as) have? arsenic…
5
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question 4 if the atomic radius of a metal that has the body - centered…
$0.033$
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surface tension: go to the following link (you may have to sign in with…
7. After conducting the experiment on the website, the substance with the highest number of drops before spilling (and thus the highest surface - tension) is usually water. 8. Wat…
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evaporation rate: watch this video and answer the following questions: …
4. Acetone 5. Water 6. Acetone evaporates fastest as it has only dipole - dipole forces. Ethanol has hydrogen bonding and dipole - dipole forces, so it evaporates slower than acet…
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1. what happened when the charged balloon was brought near water? 2. wh…
1. The stream of water bends towards the charged balloon. 2. There is no noticeable effect on hexane. 3. Water is polar (due to its Lewis - structure based dipole moment) and is a…
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nutrient cycling 1. what is the law of conservation of matter? 2. which…
1. Matter cannot be created or destroyed in a chemical reaction, only changed in form. 2. Carbon, nitrogen, phosphorus, water.
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the video tells us that the mantle of the earth today is , and the core…
solid; liquid outer and solid inner
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another nonsilicate mineral is called pyrite. now, do a quick search on…
C. iron and sulfur
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acetone (ch₃coch₃) ethanol (ch₃ch₂oh) lewis structure polar? y/n interm…
| | Acetone ($CH_3COCH_3$) | Ethanol ($CH_3CH_2OH$) | |--|--|--| | Lewis Structure | Central carbon of $C = O$ bonded to two $CH_3$ groups; carbon - oxygen double bond, carbon - h…
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(u3:1) build an atom - phet virtual lab learning goals: review of atoms…
- What is an atom? An atom is the fundamental unit of matter, composed of sub - atomic particles including protons, neutrons, and electrons. - Difference between an atom and an el…
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lewis structures: complete the table | | water (h₂o) | hexane (ch₃ch₂ch…
| | Water ($H_2O$) | Hexane ($CH_3CH_2CH_2CH_2CH_2CH_3$) | |--|--|--| | Lewis Structure | H - O - H with two lone - pairs on oxygen | Chain of six carbon atoms with appropriate hy…
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5. for each of the following molecules in the table below, determine if…
| Molecule | Electronegativity Values | Difference in Electronegativity | Bond Type | | ---- | ---- | ---- | ---- | | H - Cl | H: 2.1, Cl: 3.0 | 0.9 | Polar | | H - H | H: 2.1, H:…
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select all the correct answers. when wax is heated, it turns into a liq…
The molecules gain energy. The space between the molecules increases.
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select the correct answer from each drop - down menu. a molecule of chl…
Chlorine is an element. Carbon dioxide is a compound.
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match the vocab term with the definition. exothermic chemical change ph…
exothermic - When a substance releases energy, so it feels warm/hot chemical change - change that results in the formation of one or more new substances physical change - a change…
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how are elements in the same group on the current periodic table simila…
A. They have the same number of outermost electrons.
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how does sodium (na) compare to chlorine (cl) on the periodic table of …
A. Sodium (Na) is a highly reactive metal, while chlorine (Cl) is a highly reactive gas.
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select the correct answer. in his science class, mr brown heats a small…
E. sublimation
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3 li lithium 6.94 the element above has 6.94 protons, 3 elect
The element has 3 protons and 3 electrons.
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three metals from group 1 on the periodic table were tested for reactiv…
D. It increases down a group on the Periodic Table.
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three metals from group 1 on the periodic table were tested for reactiv…
D. It increases down a group on the Periodic Table.
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three metals from group 1 on the periodic table were tested for reactiv…
D. It increases down a group on the Periodic Table.
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three metals from group 1 on the periodic table were tested for reactiv…
D. It increases down a group on the Periodic Table.
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which best describes a solid produced in a solution during a chemical r…
D. precipitate
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which is indicated if a gas forms when two or more substances are mixed…
B. chemical change
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how would a scientist identify an element as a noble gas? a. the scient…
C. The scientist would show that the element is a nonmetal with 8 valence electrons.
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practice atom diagrams: fill in the missing information and draw the el…
| Element | Helium | Carbon | Fluorine | |--|--|--|--| | Electrons: | 2 | 6 | 9 | | Protons: | 2 | 6 | 9 | | Neutrons: | 1 | 5 | 8 | | Mass | 3 amu | 11 amu | 17 amu | | Charge | …
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which explains how the metalloids on the periodic table of elements are…
C. Metalloids all have metal and nonmetal properties.
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11 use the periodic table. match each statement with the proper classif…
contains many solids: Metals conducts electricity in the solid state: Metals tends to gain electrons and form negative ions: Nonmetals aluminum: Metals argon: Nonmetals
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drag each label to the correct category. human activities that do not c…
Eco - Friendly: recycling materials, growing trees, using fewer disposables Not Eco - Friendly: filling landfills, cutting trees, burning fossil fuels, burying organic matter
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66. what kind of tension is recommended to straighten the hair with blo…
66. Firm but gentle tension. 67. Fine, damaged, chemically - treated hair. Use lower heat and wide - tooth comb instead. 68. Close to the hair (about 1 - 2 inches) and follow the …
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the image shows a molecular model of a compound using balls and sticks.…
B. The balls must be the same color
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10 what is the correct ordering of the groups from left to right in the…
1. Alkali Metals 2. Transition Metals 3. Halogens 4. Noble Gases
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out of all the social media tools available today, the best place to st…
Marketing and advertising tools because they can help you identify people who are interested and talking about your brand.
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which of the following laboratory tools is used to grind chemical compo…
El mortero y pestillo (la última imagen)
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which of the following laboratory tools is used to grind chemical compo…
Mortero y pestillo (no se muestra en las opciones dadas, pero es la correcta; entre las opciones dadas, no hay la respuesta correcta)
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2. enumere tres isótopos estables y tres isótopos inestables que respal…
Isótopos estables: - ${}_{6}^{12}\text{C}$ - ${}_{8}^{16}\text{O}$ - ${}_{11}^{23}\text{Na}$ Isótopos inestables: - ${}_{92}^{238}\text{U}$ - ${}_{1}^{3}\text{H}$ - ${}_{6}^{14}\t…
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which of the following electron configurations is correct for nitrogen?…
A. \(1s^{2}2s^{2}2p^{3}\)
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which of the following laboratory tools is used together with filter pa…
Funnel
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which of the following is the noble gas notation shorthand for the elem…
a) [Ar] 4s²3d³, c) [Ar] 4s²4d³
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how many moles are in 36.04 grams of water (h2o)?
2 moles
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how many moles are in 30.04 grams of water (h2o)?
$1.67$ moles
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which of the following electron configurations is the correct one for t…
d) 1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁵
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1 self - check activity for questions 1 - 11, complete each statement b…
1. Chemistry 2. inorganic, physical, analytical 3. central science, energy 4. natural phenomena, materials 5. discoveries 6. Measurement tools 7. observations, hypotheses, theorie…
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question 1 out of all the social media tools available today, the best …
C. Marketing and advertising tools because they can help you identify people who are interested and talking about your brand.
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which statement best describes the rhyme schemes of the author to her b…
Bradstreet uses couplets for their overall rhyme scheme and structure. Wheatley uses couplets to enhance the poem as a song of praise for creation.
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the primary motivation behind basic research is to o develop new produc…
1. B. gain knowledge 2. D. lags behind basic research on the same substance
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determine what element is denoted by the following electron configurati…
Mg
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the study of the composition, structure, and properties of matter; the …
C. chemistry
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determine what element is denoted by the following electron - configura…
Ba
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two chemistry students are investigating the properties of quartz cryst…
B. inorganic chemistry
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the branch of chemistry that deals with substances containing carbon is…
C. organic chemistry
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which of the following is the correct noble gas notation(shorthand) for…
b) [Kr] \(5s^{2}4d^{10}5p^{2}\)
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chemistry is usually classified as a biological science. a physical sci…
B. a physical science
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a scientist is working on developing refrigerants that do not release c…
B. applied research
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using mathematical models and computer models to understand a chemical …
D. theoretical chemistry
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the branch of chemistry that involves the study of substances and proce…
B. biochemistry
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how many grams of co2 are there in 2.5 moles? 44.01 g 125.22 342.23 g 1…
110.03 g
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the definition of a chemical is a toxic substance made in a laboratory.…
any substance that has a definite composition
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all of the following are strong points of comparison. check any you inc…
All of the above can be included as strong points in a comparison paragraph.
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which of the following is the noble gas notation/shorthand for the elem…
c) [He]2s²2p²
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approximately how many atoms are in 12.6 grams of oxygen (o)? 2.37 x 10…
B. $4.74\times10^{23}$
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how many atoms are there in 1.2 moles of carbon? (a) 18.02 (b) 6.62 x 1…
$7.23\times 10^{23}$
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what do the superscripts represent in electron configurations? nothing.…
number of electrons
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solve the problem. 5) in a chemistry class, 7 liters of a 4% silver iod…
D. 3.5 L
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determine what element is denoted by the following electron configurati…
As
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3. describe the process of polymerization. (use the terms polymer and m…
Polymerization is the process by which monomers combine to form a polymer. Monomers are small molecules that act as building blocks, and through chemical reactions, they link toge…
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what is the molar mass of water? 18.02 g/mol 12.01 g/mol 33.02 g/mol 22…
18.02 g/mol