化学
化学反応、化学量論、分子構造、元素の性質。
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which of the following is a physical change? * 1 point burning wood rus…
C. Breaking glass
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3. (2 pts) the vapor pressure of ethanol is 115 torr at 34.9°c. if δh_v…
$0^{\circ}\text{C}$
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question 8 (1 point) listen the three particles that make up an atom ar…
False
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question 6 (1 point) protons and neutrons are found inside the nucleus …
True
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which subatomic particle has a negative charge and is found outside the…
Electron
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question 4 (1 point) what is the center of an atom called? nucleus prot…
A. Nucleus
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what is chemistry the study of? the study of living organisms the study…
The study of what matter is made of, how it's structured, and how it changes or reacts with other substances
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time and change 5. use map d, new babylonian empire, to sequence the fo…
1. a. Babylonians fail to conquer Egypt. 2. b. Babylonians conquer Nineveh. 3. c. Babylonians conquer Jerusalem. 4. d. Persians attack Babylon. 5. e. Babylonians conquer Carchemis…
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which change is likely to happen to an atom of the element strontium (s…
It will give up electrons, forming a positive ion
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answer the following questions. 1) how many molecules are present in 20…
1. Approximately $7.83\times 10^{23}$ molecules 2. Approximately $19.6$ g 3. Approximately $1.32\times 10^{23}$ molecules 4. Approximately $1.91\times 10^{24}$ molecules 5. Approx…
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how many valence electrons are in an atom of the element fluorine? (1 p…
D. seven
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why do atoms exchange or share electrons during bonding? (1) to obtain …
to obtain a full outer electron shell
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what are valence electrons? (1 point) electrons that are shared between…
the electrons in an atom's outermost energy level
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10)one drop of water weighs 0.040 g. how many molecules are there in on…
10) Approximately $1.33\times 10^{21}$ molecules 11) Approximately $4.63\times 10^{15}$ molecules 12) 3 moles, approximately $1.8066\times 10^{24}$ molecules 13) Approximately $1.…
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which feature defines a neutral atom? (1 point) the ability to change t…
the number of electrons equal to the number of protons
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what is the main style difference between oses\ and ight\? oses\ uses i…
"Roses" uses iambic pentameter.
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avogadros number (6.02 x 10²³) was not discovered by him, but named in …
1. Approximately $4.32$ g 2. $3.18\times10^{23}$ molecules 3. $177.5$ g 4. $76.8$ L 5. $1.806\times10^{24}$ atoms 6. $384.8$ g 7. Approximately $0.0545$ mol 8. Approximately $0.05…
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problem 3: the freezing point of benzene is lowered by 1.2 °c when 1.50…
$128\ g/mol$
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question 15 why does ice stay at the top of oceans instead of sinking t…
Question 15: A. Ice is less dense than liquid water Second question: Water has a high heat capacity
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15. chart of neurotransmitters neurotransmitter function(s) malfunction…
| Neurotransmitter | Function(s) | Malfunction(s) | | ---- | ---- | ---- | | Acetylcholine (ACh) | Muscle - contraction, memory, learning | Alzheimer's disease (low levels) | | Do…
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les miroirs pivotants lorsquon fait pivoter un miroir plan sans changer…
a) Le rayon réfléchi pivote de $10^{\circ}$ car l'angle de pivotement du rayon réfléchi est le double de l'angle de pivotement du miroir. b) La distance séparant l'observateur de …
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doc. 8 excerpts from the suppressed speech of wamsutta, 1970 to have be…
Plymouth's descendants wanted a complimentary, myth - based speech about friendly relations. Wamsutta wanted to expose the injustices like land - taking, attempts to convert and c…
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explain how air pressure changes as you travel away from earths surface…
As you travel further from the Earth's surface through the atmosphere, air pressure decreases because there is less air above exerting weight. This causes gas molecules in the atm…
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make the following conversions. express your answers in scientific nota…
a. $1.48\times 10^{7}\text{ }\mu\text{g}$ b. $3.72\times 10^{0}\text{ g}$ c. $6.63\times 10^{4}\text{ cm}^{3}$ d. $7.5\times 10^{1}\text{ kJ}$ e. $3.9\times 10^{3}\text{ dg}$ f. $…
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in addition to science courses like physics and chemistry, what other t…
B. computer science
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what is an atomic nucleus? a positive charge that is spread throughout …
C. positively charged region at the center of the atom
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true or false 8 there are about 400 known elements 9 all of the element…
8. False 9. True 10. False Extra Credit: Earth, Air, Fire, Water
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7. how many grams of fuctose (c6h12o6) must be dissolved in 419 g of be…
107.4g
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which of the following candidates would be most prepared for a career i…
Sharon, who has a PhD in chemistry and is willing to move to any city for a job
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3. the theory of ______ of matter states that matter cannot be created …
3. conservation 4. Matter 5. volume 6. element 7. properties True or False: False True
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select the lewis structure that most accurately represents selenium dic…
The first structure (top - left in the image) with single bonds between Se and Cl and lone pairs on all atoms is the correct one.
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q15. what is the volume of the solid in the following picture? mass = 5…
$2.7\ mL$
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zinc sulfide is used in glow - in - the - dark face paint. write the ch…
$ZnS$
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because they penetrate the visible surface of a painting, ultraviolet a…
A. It can provide new information about the attributed artist's practices.
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when added to a solution containing a carbon - carbon double or triple …
$KMnO_4$
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radioactive forms of rubidium chloride are used to help doctors evaluat…
$RbCl$
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zirconium(iv) fluoride is used to make special glass for fiber - optic …
$ZrF_{4}$
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strontium oxide was used in the glass screens of cathode - ray tube (cr…
SrO
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ammonium sulfide is a polyatomic ionic compound. when applied to bronze…
$(NH_4)_2S$
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17 which element is in group 3a and period 4? gallium calcium silicon n…
Gallium
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1. what is the most stable group on the periodic table? why is this gro…
1. The noble - gas group (Group 18) is the most stable due to a full outer - electron shell. 2. The most reactive groups are the alkali metals (Group 1) and halogens (Group 17). A…
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match element based on the number of valence electrons a neutral atom w…
Magnesium: 2 valence electrons Argon: 8 valence electrons Oxygen: 6 valence electrons Aluminum: 3 valence electrons Bromine: 7 valence electrons Lithium: 1 valence electron
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ammonium iodide is a polyatomic ionic compound. it was historically use…
$\text{NH}_4\text{I}$
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to rent a certain meeting room, a college charges a reservation fee of …
$t<10$
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atomic models protons, electrons, and neutrons are three types of parti…
Sketch each atom as described above with correct number of protons, neutrons in nucleus and electrons in electron - shells.
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iron(ii) carbonate is a polyatomic ionic compound. it is the primary co…
$FeCO_3$
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below, fill the name of the type of chemical reaction displayed by the …
- For "Particles combine to make new one": Synthesis reaction - For "Particle breaks apart": Decomposition reaction - For "Particle combinations changed": Double - displacement re…
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ammonium chloride is a polyatomic ionic compound. it is an active ingre…
$NH_4Cl$
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3 which of the following statement is true about carbon-12 and carbon-1…
Carbon-12 and Carbon-13 have the same number of protons but different number of neutrons.
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12 what is the correct answer for the square? 8 -2 27 9 17 protons: 8 n…
-2
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aluminum phosphide is a binary ionic compound. it is used as a pesticid…
$AlP$
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sodium bromide is a binary ionic compound. it is used to prevent the ov…
$NaBr$
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protons: 8 neutrons: 10 electrons: 10 what is the total charge?
-2
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barium oxide is a binary ionic compound. it is used in special camera l…
$BaO$
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silver bromide is a binary ionic compound. it is used in black - and - …
AgBr
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chapter 12 boiling point elevation practice worksheet 1. what is the bo…
$73.4^{\circ}C$
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suchita is going to make an energy transfer diagram to represent the en…
The arrow for heat is the widest output arrow.
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9 how many neutrons are in li(lithium)? assume that the mass is 7. 10 w…
4
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8 how many protons are in calcium? 2 19 20 40
20
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how many protons are in calcium? 2 19 20 40
20 (corresponding to the third option in the multiple - choice list)
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what is the atomic number of the following element? 10 20 19 39 19 k po…
19
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5 how many valence electrons are in f(fluorine)? 9 10 2 7 6 from the di…
7 Since we can't see the diagram for question 6, we can't answer it. But for question 5, the above is the solution.
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from the below picture, how many valence electrons are present? 5 3 7 2
7
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what is the mass of an atom with 5 protons, 7 neutrons, and 5 electrons…
12
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3 what is the mass of an atom with 5 protons, 7 neutrons, and 5 electro…
12 (corresponding to the fourth option in the first question)
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1 the period number of an element indicate the number of electron energ…
1. number of electron energy levels 2. Electron
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a certain drug is made from only two ingredients: compound a and compou…
142 milliliters
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this photograph was taken in during the progressive era. what was the r…
C. The ratification of the Nineteenth Amendment
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chemistry: ions in chemical compounds name: micah carter hour: 7 date: …
| Ions | Chloride $Cl^{-}$ | Hydroxide $OH^{-}$ | Nitrate $NO_{3}^{-}$ | Sulfate $SO_{4}^{2 - }$ | Sulfide $S^{2 - }$ | Carbonate $CO_{3}^{2 - }$ | Phosphate $PO_{4}^{3 - }$ | | -…
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name symbol atomic number number of protons number of valence electrons…
| Name | Symbol | Atomic Number | Number of Protons | Number of Valence Electrons | | ---- | ---- | ---- | ---- | ---- | | hydrogen | H | 1 | 1 | 1 | | lithium | Li | 3 | 3 | 1 | …
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write the chemical formula for each of the following compounds. 6. carb…
16. CO 17. FeO 18. $P_{2}O_{5}$ 19. $H_{2}SO_{4}$ 20. $SO_{2}$
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an atom has 13 electrons. how many protons does it have?
13
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names and formulas of compounds write name for each of the following co…
1. sodium sulfide 2. ammonium chloride 3. copper(I) fluoride 4. copper(II) fluoride 5. lead(II) sulfate 16. CO 17. FeO 18. P₂O₅ 19. H₂SO₄ 20. SO₂
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quiz: first 20 elements, atomic structure, and periodic write the eleme…
1. Calcium 2. K 3. Argon 4. Cl 5. S 6. P 7. Silicon 8. Aluminum 9. Mg 10. Sodium 11. Neon 12. F 13. Beryllium 14. He 15. Carbon 16. Period 17. Group 18. Valence 19. Protons 20. 38…
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what determines the vast majority of an atoms properties?
The electron configuration of the atom.
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assuming 50 tons of pressure, at which temperatures is benzene a solid,…
A. It is a solid at 7 degrees, a liquid at 10 and 16 degrees, and a gas at 32 degrees celsius. D. It is a solid at 5 degrees, a liquid at 7 and 10 degrees, and a gas at 16 degrees…
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question 10 what of the following best describes soil liquefaction? a w…
A. when saturated soil behaves like a liquid
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12. what volume of distilled water must be added to 105 ml of 0.600 - m…
52.5 mL
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12. what volume of distilled water must be added to 105 ml of 0.600 - m…
$52.5\ mL$
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about mass numbers and atomic numbers to complete the table. name atomi…
| Name | Atomic Number | Number of Protons | Number of Neutrons | Mass Number | | ---- | ---- | ---- | ---- | ---- | | helium | 2 | 2 | 2 | 4 | | carbon | 6 | 6 | 6 | 12 | | oxyge…
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the atomic number and the mass number of atoms relate to their numbers …
| Name | Atomic Number | Number of Protons | Number of Neutrons | Mass Number | | ---- | ---- | ---- | ---- | ---- | | helium | 2 | 2 | 2 | 4 | | carbon | 6 | 6 | 6 | 12 | | oxyge…
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the formula for the sulfate ion is so₄²⁻. based on this information, wh…
A. $MgSO_{4}$, D. $K_{2}SO_{4}$
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strontium chloride is an ionic compound. it is used in fireworks to pro…
D. $[\ddot{Cl}:]^{-}[Sr]^{2 +}[\ddot{Cl}:]^{-}$
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garnets are a class of minerals which exist in many colors. theyre ofte…
$Ca^{2 + }$ and $SiO_{4}^{4 - }$: Ionic $Al^{3+}$ and $SiO_{4}^{4 - }$: Ionic $Si$ and $O$: Covalent
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group 17 elements are called halogens. halogen means \salt former,\ der…
To produce stable ions, halogens gain 1 electron(s) to form ions with a - 1 charge.
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chemical substances were originally named based on their properties, di…
Celestite (strontium sulfate): $SrSO_{4}$ Arcanite (potassium sulfate): $K_{2}SO_{4}$ Gypsum (calcium sulfate): $CaSO_{4}$
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question select the correct answer from each drop - down menu. complete…
First drop - down: 6 Second drop - down: 6 Third drop - down: 2 Fourth drop - down: 4
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a common chemical reaction involves two ionic compounds that exchange i…
For reactants: C. $AlBr_{3}+Na_{3}PO_{4}$ For products: B. $NaBr + AlPO_{4}$
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fill in the table by selecting the correct iupac name for each formula.…
RbCl: Rubidium chloride BeS: Beryllium sulfide Ba(C₂H₃O₂)₂: Barium acetate CsClO₃: Cesium chlorate
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originally, chemical substances were named based on their origins or pr…
Quicklime: $CaO$ Limestone: $CaCO_{3}$ Fluorite: $CaF_{2}$
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the formula for the sulfate ion is so₄²⁻. based on this information, wh…
A. $MgSO_{4}$, D. $K_{2}SO_{4}$
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hypobromite is a polyatomic ion with formula bro⁻. it is produced by th…
43 protons 44 electrons
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sodium hydroxide, also called lye, is an ingredient in many soaps. it i…
A. NaOH
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hydroxyapatite is composed of calcium ions (ca²⁺), phosphate ions (po₄³…
$Ca^{2 + }$ and $PO_{4}^{3 - }$: Ionic $P$ and $O$: Covalent $O$ and $H$: Covalent $PO_{4}^{3 - }$ and $OH^-$: Ionic $Ca^{2 + }$ and $OH^-$: Ionic
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44. water is known as the universal because it is able to dissolve more…
44. Solvent 45. Solvent; Solute 46. Polar; Positive; Negative 47. Specific - heat capacity; Heat; Temperature 48. does not 49. Cools 50. Dense; Float; Liquid 51. Neutral; 7; Equal…
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what was rutherfords atomic model called? * planetary model plum puddin…
1. Nuclear Model 2. Alkali Metals
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how many electrons does this ion have? * 10 points 34 16 s - 2 18 how m…
How many electrons does this ion have? 18 How many neutrons does this atom have? 18
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lesson 5 assignment: concentration ii part 1 1. a 180 - ml disinfectant…
1. Approximately 47.2% 2. 12% 3. Approximately 0.017% 4. Approximately 3260.9 ppm 5. 912 mL
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if you were to add a proton to a neutral atom what would change? (check…
1. E. All of the above 2. C. Atomic Mass
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which of the element(s) below have similar properties as calcium? (chec…
Radium, Magnesium