化学
化学反应、化学计量、分子结构与元素性质。
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use the following information to answer the next question. according to…
2.36 moles
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8. a student completes an analysis of a chemical reaction between magne…
2.63
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7. the number of moles present in 90.0g of lead(iv) oxide is 2.66 moles…
0.376 moles
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6. if 60.0 g of barium and 5.00 g of phosphorus are available to react,…
phosphorus
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multiple choice 5. which compound has the largest molecular mass? □ zn(…
$Zn(H_2PO_4)_2$
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use the following information to answer the next question. in an experi…
84.0%
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3. a lab technique that allows you to separate a precipitate from solut…
Filtration
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multiple choice use the following information to answer the next questi…
2 and 4
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1. when the equation for the complete combustion of propene (c₃h₆(g)) i…
9
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the passage below describes an experiment. read the passage and then fo…
a dependent variable
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ms. jacksons class is learning about compounds. a specific molecule is …
6:5
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in the center of matterville, there is a place called the nucleus arcad…
The morale of Matterville would be disrupted as the balance between negative Electrons and positive Protons is broken.
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part c: electron configuration 12. how many electrons can each level ho…
12. 2, 8, 8 13. Valence electrons 15. - Li: # of P = 3, # of N = 4, # of E = 3 - Ne: # of P = 10, # of N = 10, # of E = 10 - Mg: # of P = 12, # of N = 12, # of E = 12 - Cl: # of P…
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substance appearance odour hardness dissolves in water? conductivity in…
| Substance | Ionic or molecular? | |--|--| | moth balls | molecular | | sodium thiosulfate | ionic | | antifreeze | molecular | | potassium permanganate | ionic | | benzoic acid …
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atomic basics part a: atomic structure 1. draw five protons in the nucl…
| Element | Atomic Number | Atomic Mass | Protons | Neutrons | Electrons | | ---- | ---- | ---- | ---- | ---- | ---- | | Li | 3 | 7 | 3 | 4 | 3 | | P | 15 | 31 | 15 | 16 | 15 | | …
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the closeness of particles of gas and their low speeds allow intermolec…
This is a limitation of the kinetic - molecular theory.
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which event is most likely occurring? o diffusion because particles mov…
diffusion because particles move from regions of high concentration to regions of low concentration
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which observation indicates that the kinetic - molecular theory has lim…
Increasing collisions of gas molecules will increase energy between them.
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the table below gives some characteristics of element y. |characteristi…
B. B
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what is the atomic number of zirconium? 39 40 41 42
B. 40
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which best explains why ionization energy tends to decrease from the to…
Electrons get farther from the nucleus.
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which element is classified as an alkali metal? rb sr zr cl
A. Rb
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which is a correct set of values of m for one of the subshells of n = 2…
-1, 0, 1
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which statement best describes how electrons fill orbitals in the perio…
Electrons fill orbitals in order of their increasing energy from left to right.
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in which orbitals would the valence electrons for selenium (se) be plac…
s orbital and p orbital
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to show the electron configuration for an atom, when would it be better…
when the aim is to show electron spins
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a single atom of an element has 11 protons, 11 electrons, and 12 neutro…
B. Na
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which substance is a mixture? o table salt o gasoline o aluminum o carb…
gasoline
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when electrons are removed from the outermost shell of a calcium atom, …
a cation that has a smaller radius than the atom.
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which element has the largest atomic radius? o as o n o p o sb
Sb
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among the elements of the main group, the general trend in the first io…
The ionization energy decreases because the full s orbital shields the electron entering the p orbital.
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which physical method can be used for obtaining a sample of salt from a…
boiling
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how many valence electrons does aluminum (al) have available for bondin…
C. 3
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air is made up of different gases, such as oxygen, nitrogen, and carbon…
Oxygen, nitrogen, and carbon dioxide are all classified as pure substances.
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which element has 32 protons in its nucleus? phosphorus cobalt germaniu…
germanium
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which of the following symbols would be included in the noble gas notat…
B. Kr
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the elements of which group are nonreactive? halogens alkaline earth me…
C. noble gases
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hydrogen has three isotopes ¹h, ²h, and ³h. what is the difference betw…
The number of neutrons ranges from 0 to 2.
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which element is the most reactive? o sodium o nickel o carbon o oxygen
sodium
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which characteristic is given by the angular momentum quantum number? o…
orbital shape
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what is an example of a chemical change?
Burning wood
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which would least strongly attract electrons from other atoms in a comp…
elements of group 1
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which element would release the most energy while adding an electron to…
C. Br
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electronegativities of the elements na, al, p, and cl follow a specific…
Cl
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electronegativities of the elements be, mg, ca, and sr follow a specifi…
Sr
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which element has a larger atomic radius than sulfur? chlorine cadmium …
B. cadmium
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how does a lithium cation compare to a lithium atom? the cation is larg…
The cation is smaller.
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which explains the change in ionization energy that occurs between remo…
The ionization energy increases because the ratio of the protons to electrons increases.
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among the elements of the main group, the first ionization energy incre…
A. from left to right across a period.
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which element has the smallest atomic radius? calcium potassium scandiu…
D. titanium
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which element would most likely have an electron affinity measuring clo…
Ar
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21. the table below describes four atoms. atom a atom b atom c atom d n…
B. A and D represent the same element
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which element does the electron configuration 1s²2s²2p² represent? o b …
B. C
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what does a catalyst do in a chemical reaction?
A catalyst lowers the activation energy and increases the rate of a chemical reaction without being consumed.
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which is the noble gas notation for chlorine? ne 4s² 4p⁵ ne 3s² 3p⁵ ne …
[Ne] 3s² 3p⁵
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how many valence electrons does lithium (li) have available for bonding…
1. Option Text
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it is easier to determine the electron configurations for the p - block…
their electrons are assigned to s and p orbitals only.
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hydrogen reacts with an element to form a compound. which element would…
B. chlorine
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in which block of the periodic table is chromium (cr) found? s block d …
B. d block
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which is the electron configuration for nobelium (no)? rn7s²5f¹⁴ rn7s²5…
[Rn]7s²5f¹⁴
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in which block of the periodic table is uranium (u) found? ○ s block ○ …
f block
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what is the difference between a chemical change and a physical change?
A chemical change creates new substances with different chemical properties by changing chemical bonds. A physical change only modifies physical properties without altering chemic…
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what is an atom made up of?
An atom is made up of a nucleus containing protons and neutrons, with electrons orbiting the nucleus.
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what careers use chemical reactions to solve problems?
Chemist, Chemical engineer, Pharmacist
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a) chlore et magnésium. b) silicium et oxygène. c) soufre et sodium. d)…
### a) $NaOH$, Hydroxyde de sodium ### b) $NH_4F$, Fluorure d'ammonium ### c) $K_2CO_3$, Carbonate de potassium ### d) $LiNO_3$, Nitrate de lithium ### e) $Ca_3(PO_4)_2$, Phosphat…
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a) chlore et magnésium. b) silicium et oxygène. c) soufre et sodium. d)…
a) Formule chimique : $MgCl_{2}$, Nom du composé : Chlorure de magnésium b) Formule chimique : $SiO_{2}$, Nom du composé : Dioxyde de silicium c) Formule chimique : $Na_{2}S$, Nom…
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part b while studying chemical and physical changes, students added sal…
B. No, it is a physical change. It is salt and water and you can get the salt back by boiling off the water.
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according to the us food and drug administration (fda) what must any pr…
at least 95% organically produced ingredients
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what happens when sugar dissolves in water? the sugar is turned into a …
The sugar particles spread out evenly in the water.
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give the chemical formula and chemical name that would result from the …
Chemical Formula: $SrS$ Chemical Name: strontium sulfide
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determine what elements are denoted by the following electron configura…
21. S 22. Rb 23. Sb 24. Os 25. Es 26. Not valid 27. Not valid 28. Not valid 29. Valid 30. Not valid
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1. what is the name of each labeled subatomic particle? a: electron b: …
3. Mass number: 9 4. Symbol: $Be$. It has 4 protons, and beryllium has an atomic number of 4. 5. Charge: 0. The number of protons (4) equals the number of electrons (4).
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11. refer to the bohr models above: element c is in period ___. element…
Element A is in group 6. Element B is in group 2. Element A is in a higher period. Element B has a lower shielding effect compared to Element C. Element C is in a higher period.
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prompt: in a couple of complete 5 to 7 sentence paragraphs, using evide…
Physical properties are characteristics of a substance that can be observed or measured without changing the substance's chemical identity. Examples include color, density, and me…
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give the chemical formula and chemical name that would result from the …
Chemical Formula: $CsF$ Chemical Name: cesium fluoride
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1. what is the name of each labeled subatomic particle? a: electron b: …
Protons: 4 Neutrons: 5 Electrons: 4
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11. refer to the bohr models above: element c is in period ___. element…
Rb: + 1 Br: - 1 N: - 3 Al: + 3 Mg: + 2 S: - 2
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mark which best describes the ionic compound that would result from the…
Ionic compound with a strength of 4
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structure of the atom the following diagram shows an atom. use the diag…
a: Electron b: Proton c: Neutron
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11. refer to the bohr models above: element c is in period ___. element…
Rb: + 1 Br: - 1 N: - 3 Al: + 3 Mg: + 2 S: - 2
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mark which best describes the ionic compound that would result from the…
None of the given options correctly describe the ionic compound formed from rubidium and fluorine.
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mark which best describes the ionic compound that would result from the…
No ionic compound is formed since you do not have a metal and a nonmetal
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using the periodic table, complete the table to describe each atom. typ…
A. 8 B. 15 C. O D. 26 E. 30 F. Fe
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mark which best describes the ionic compound that would result from the…
No ionic compound is formed since you do not have a metal and a nonmetal
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mark which best describes the ionic compound that would result from the…
lonic compound with a strength of 6
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mark which best describes the ionic compound that would result from the…
No ionic compound is formed because a noble gas does not react
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protons neutrons number number (symbol) 20 20 a b c 9 d e 19 f using th…
A. 20 B. 40 C. Ca D. 10 E. 9 F. F
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mark which best describes the ionic compound that would result from the…
Ionic compound with a strength of 4
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mark which best describes the ionic compound that would result from the…
Ionic compound with a strength of 2
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19. in a lab, the melting point of salicylic acid is measured to be 45.…
19. $1.36\%$ 20. $4.25\%$
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why is mixing a salad considered a physical change? mixing is another e…
The ingredients stay the same, just combined.
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click the link here to open the atom - building interactive, and click …
1. 2 2. 1 3. 7 4. 3
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why is shredding paper a physical change? the paper is still paper, jus…
The paper is still paper, just in smaller pieces.
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doreen schmidt is a chemist. she needs to prepare 24 ounces of a 9% hyd…
12 ounces of the 6% acid solution and 12 ounces of the 12% acid solution should be in the mixture.
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7. in general, the atomic radius (increases, decreases) from top to bot…
7. Increases; Decreases; Decreases; Increases 8. d. B because it is harder to remove a valence electron from B. 9. c. B because it is a nonmetal and wants to gain electrons. 10. (…
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drag each component of an argument to the statements that fit those com…
claim: Atoms cannot be created nor destroyed in a chemical reaction. reasoning: Balanced equations always begin and end with the same number of each element; The periodic table of…
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dawn schmidt is a chemist. she needs to prepare 24 ounces of a 9% hydro…
12 ounces
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drag the chemical expression to the number of atoms. > get help here zn…
ZnCl₂ - three atoms 2HCl - four atoms Zn - one atom H₂ - two atoms
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19. in a lab, the melting point of salicylic acid is measured to be 45.…
26. 2 27. 4 28. 3 29. 4 30. 1 31. 2 32. 4 33. 4 34. 3 35. 2 36. 3
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7. what are produced when a base is mixed with water? a. hydrogen ions …
7. b. hydroxide ions 8. c. hydrogen bonds