化学
化学反应、化学计量、分子结构与元素性质。
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how does the droplet diameter compare between polar and nonpolar substa…
B. Droplets are smaller for polar substances
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question 15 (1 point) why do polar droplets show greater cohesion? a th…
A. They are rounder due to hydrogen bonding
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why do elements with an atomic number greater than that of lead tend to…
They emit radiation in the form of particles or electromagnetic waves.
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17. a is defined as a naturally occurring inorganic solid with a specif…
17. Mineral 18. Igneous, Sedimentary, Metamorphic
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multiple - choice question how are the atoms of various elements differ…
they are different sizes and weights
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multiple - choice question what are \compounds\? combinations of the sa…
C. combinations of 2 elements to make something new
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what are the 3 states of matter at room temperature? liquid, solid, gas…
liquid, solid, gas
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multiple - choice question what makes something an element? it cannot b…
It cannot be broken down into smaller parts
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which of prosperos actions most clearly indicates that he is manipulati…
A. He puts Miranda to sleep with his magic so he can plan other schemes.
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manganese (mn) is element 25 on the periodic table. a sample contains 9…
$0.151$ mol Mn
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question 7 (1 point) why do you think hydrogen bonds break and reform q…
A. They are weaker than covalent bonds
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multiple - choice question how do chemical reactions effect substances?…
combine them into new substances
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4. what is the main component of limestone? aluminum silicate magnesium…
D. Calcium carbonate
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hypothesize: note the yellow lines that form between molecules, which r…
D. Opposite partial charges attract
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protons: 7 neutrons: 7 electrons: 10 what is the mass number?
14
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what is the total charge?
+1
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protons: 10 neutrons: 10 electrons: 10 what is the mass number?
20
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what is the mass number?
2
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multiple - choice question what is found on the periodic table? your ey…
B. All of the known elements
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protons: 9 neutrons: 10 electrons: 10 find the element: is it: ○ neutra…
Element: Fluorine (F) Is it: Ion
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find the element: is it: ○ neutral atom ○ ion
Helium (He), Neutral Atom
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¿qué sucede en una prueba de llama? a. se funde una muestra en una llam…
D. Los electrones se excitan a niveles de energía más altos y se observan sus emisiones.
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¿cuánto cu - 61 (vida media de aproximadamente 3 horas) quedaría de una…
# Explicación: ## Paso 1: Calcular el número de vidas medias El tiempo transcurrido es de 9 horas y la vida media es de 3 horas. Entonces, el número de vidas medias $n=\frac{9}{3}…
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¿cuál es el segundo número cuántico del electrón 3 p^1 en el aluminio, …
# Explicación: ## Paso 1: Identificar el orbital El orbital es 3p. El primer número cuántico principal \(n = 3\). El segundo número cuántico, el número cuántico orbital angular \(…
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electrons: 10 neutrons: 8 protons: 8 find the element: is it: ○ neutral…
The element is oxygen. It is an ion.
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pregunta 1 de 25 ¿qué información da el primer número cuántico de un el…
# Breve Explicación: El primer número cuántico, conocido como el número cuántico principal (n), indica el nivel de energía en el que se encuentra el electrón. A medida que aumenta…
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13) choose the best answer. atomic numbers ____ across a period and ___…
13) A. increase; increase 14) B. increase; increase
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10) identify the following from this isotope. name of isotope: ___ atom…
11) C. 85.31 amu 12) C. 48.1 amu
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10) type the correct answers in the blanks below. identify the followin…
Name of isotope: neon - 21 Atomic mass number: 21 Atomic number: 10 Number of protons: 10 Number of neutrons: 11
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8) use the periodic table to write the correct answer. what is the isot…
$84_{36}\text{Kr}$ (the last option in the multiple - choice list)
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which type of reaction is shown? use the diagram to answer the question.
Chain reaction
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lesson 2: drilling for understanding 1. for each measurement given in t…
| Measurement | Suggested Tool | Reason for Suggestion | |--|--|--| | Area of the floor before ordering carpet | Tape - measure and calculator | Measure length and width, calculat…
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a student writes out an equation to represent a fission reaction. how c…
The number of atoms of each element should be the same in the reactants and products.
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an element has a lower electronegativity than boron and 1 valence elect…
Group 1, period 2
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from which atom is it easiest to remove an electron? (lowest ionization…
U
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from which atom is it easiest to remove an electron? (lowest ionization…
U
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which is the most reactive family of nonmetals? halogens alkali metals …
Halogens
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except for helium (he), how many electrons do the noble - gases have in…
8
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which of the following is the most electronegative? a b mg k
Cl
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how many grams are in 5.43 moles of no. 9? input the numeric value here…
640
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why does the atomic radius increase going from top to bottom within a c…
Increased number of energy levels
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why does the atomic radius decrease going from left to right across a p…
Increased number of protons
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look up the position on the periodic table for each element tested in t…
- The metals are found on the **left** side of the P - table. - The nonmetals are found on the **right** side of the P - table. - The Semimetals are found between the **metals** a…
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which statement is the reason why mg has a smaller atomic radius than n…
Mg has greater nuclear charge than Na.
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how are the elements in the mendeleev periodic table arranged? in order…
In order of increasing atomic number.
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use the link below to build an atom. follow the steps and then answer t…
"I found out Electrons have a negative charge. I learned Protons have a positive charge. I never knew Neutrons have a neutral charge. I now know adding Protons changes one element…
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match the following group numbers to their correct names? 1a 2a 7a 8a #…
1A - Alkali Metals 2A - Alkaline Earth Metals 7A - Halogens 8A - Noble Gases
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14) choose the best answer. atomic masses ____ across a period and ____…
C. increase, increase
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which group of elements have no electronegativity? o transition metals …
Noble Gases
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11) choose the best answer. use significant figures to solve. rubidium …
85.31 amu
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from which atom is it hardest to remove an electron? (highest ionizatio…
F
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how many neutrons does this isotope have? 48 10) type the correct answe…
Name of isotope: neon - 21 Atomic mass number: 21 Atomic number: 10 Number of protons: 10 Number of neutrons: 11
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isotopes of an element have a different number of protons but the same …
C. $_{36}^{84}\text{Kr}$
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question 1 - 9 review the following quote from machiavelli, the prince:…
A humanist approach that emphasized practical political analysis over idealism
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ii. fill - in the blanks with word bank provided. matter is anything th…
Materia, dos, pura, mezcla, sustancia pura, mezcla, elemento, compuesto, tabla periódica, símbolo químico, pura, homogénea, heterogénea, solución, fase, Mezclas heterogéneas, mezc…
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comparing reactivity of different m rank the metals from most reactive …
Silver: 3 Strontium: 1 Technetium: 2
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comparing reactivity of different m rank the metals from most reactive …
Tantalum: 1 Niobium: 2 Dubnium: 3
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comparing reactivity of different rank the metals from most reactive (1…
Titanium: 1 Nickel: 2 Darmstadtium: 3
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10. what is the formula for potassium sulfate? 11. what is the formula …
$K_2SO_4$ ### 11.
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wow! thats hysterical reading comprehension 1. what gives us our super …
1. Adrenaline (assuming general knowledge as no text provided) 2. Utmost 3. To trigger the 'fight - or - flight' response 4. A chemical messenger regulating physiological processe…
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1. what is the name of the compound fe(no3)3? 2. calculate the molar ma…
1. Iron(III) nitrate 2. 310.18 g/mol 3. Ti₃N₂ 4. N: 29.16%, H: 8.43%, C: 12.50%, O: 50.00% 5. Moles: 0.208 mol, Molecules: $1.25\times10^{23}$ molecules 6. 2.98 g 7. AlCl₃ 8. Dini…
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name this will be graded and worth 50 pts. put in your binder when you …
1. Corporate fraud and unethical behavior 2. Largest 3. Schemes 4. Telecommunications 5. Scandals 6. Tyco executives 7. Auditing Enron 8. Destroyed 9. Lost its license and shut do…
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read the paragraph, then choose the word that best completes the senten…
D. utility
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interactivity: the quantum mechanical model and atomic orbitals (lms gr…
Draw a small sphere labeled 1s centered at the origin, a larger sphere labeled 2s also centered at the origin, and a dumb - bell shaped orbital along the x - axis labeled 2p_x.
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if a built an atom with 53 protons, 58 neutrons, and 54 electrons: a. w…
a. Iodine (I) b. - 1 c. 111
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name the following type iii compounds: 17. n₂o₅ dinitrogen pentoxide 18…
17. Dinitrogen pentoxide 18. Phosphorus pentachloride 19. Oxygen difluoride 20. Carbon disulfide 21. $N_2O_4$ 22. $SO_3$ 23. $CF_4$ 24. $XeF_6$ 25. $NH_4NO_3$ 26. $K_2Cr_2O_7$ 27.…
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how many electrons does a neutral atom of bromine have?
35
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what element has a mass number of 15 and 6 neutrons?
Fluorine
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what is the mass number of carbon with 8 neutrons
14
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instructions: identify whether the descriptions below are physical or c…
1. Chemical property 2. Physical property 3. Chemical property 4. Physical property
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what element has 16 electrons and a charge of -2?
Sulfur (S)
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a molecule with five electron pairs (single bonds and/or lone pairs) ar…
I. Trigonal bipyramidal, II. Seesaw, III. T - Shaped, IV. Linear
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the number of $sigma$ bonds and $pi$ bonds in the molecule below are __…
$\sigma = 8,\pi = 3$
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at standard temperature and pressure, a 0.50 mol sample of h₂ gas and a…
A. average molecular kinetic energy
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the average kinetic energy of the gas molecules is (a) greatest in cont…
D. the same in all three containers
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3 mark for review the maxwell - boltzmann distributions of molecular sp…
A. Gas A
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which statement most accurately describes what happens when a bar of ch…
B. A physical change takes place that causes molecules to move faster.
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the experimental apparatus represented above is used to demonstrate the…
A. $HCl$ and $CH_3NH_2$
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sam says that all molecules are compounds. jac disagrees and says that …
C. Jac is correct because a molecule has at least two atoms bonded together and all compounds have at least two different atoms bonded together.
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a few weeks after chloe downloaded the apps you recommended, she tells …
A. Trello
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which picture or pictures show a molecule? a. a and c b. b only c. b an…
C. B and C
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the hybridization of the central atom in ocl₂ is ______. :cl - o - cl: …
sp³
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after agreeing with your suggestion to try out notion for tracking her …
C. Rewards that unlock music tutorials after learning sessions
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a student wrote a table comparing pure substances and mixtures. | pure …
D. Mixtures are substances that are not chemically combined.
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a molecule with five electron pairs (single bonds and/or lone pairs) ar…
D. I, II, III and IV
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jordan adds 20 grams (g) of salt and 200 g of dry beans to a pot of war…
D. a mixture that can be separated back into its parts through physical processes
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write formulas for the following type i compounds: 5. calcium iodide 6.…
5. $CaI_2$ 6. $Na_2S$ 7. $Al_2O_3$ 8. $BeBr_2$ 9. Iron(III) fluoride 10. Chromium(VI) oxide 11. Vanadium(III) chloride 12. Titanium(IV) oxide 13. $MoO_2$ 14. $Fe_2S_3$ 15. $NiCl_4…
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which of the following molecules are polar? i. ch3f ii. brf5 iii. xef2 …
I, II and IV are polar molecules
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7) true or false: energy cant be created or destroyed, it can only chan…
7. A. True 8. Adenosine triphosphate
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what is the central atom hybridization in the following ion? \begin{bma…
sp³
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read the paragraph, then choose the word that best completes the senten…
B. specialized
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if all the orbitals shown in the three - dimensional model are complete…
C. 10
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which of the following molecules are polar? i. ash3 ii. sbf5 iii. sf4 i…
E. I and III are polar
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which of the following is a balanced equation representing the reaction…
For the acetone decomposition question: $2C_3H_6O ightarrow6C + 6H_2+O_2$ For the $AlCl_3 + 3NH_4OH$ reaction question: $Al(OH)_3 + 3NH_4Cl$
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how many sigma and pi bonds are in the following molecule? sigma = 6, p…
sigma = 5, pi = 1
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which of the following molecules has a trigonal pyramidal molecular geo…
C. $\text{PCl}_3$
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according to vsepr theory, the molecular geometry of xef₂ is described …
A. linear
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b) describe what happens to the spaces between the particles and the fo…
As a substance changes from solid to liquid to gas, the spaces between the particles increase and the forces between the particles decrease.
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use the following reaction to answer the questions below: ca + n₂ -> ca…
Which element was reduced: nitrogen Which element was oxidized: calcium Which element is the oxidizing agent: nitrogen Which element is the reducing agent: calcium
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question 28 use the following reaction to answer the questions below: c…
Which element was reduced: nitrogen Which element was oxidized: calcium Which element is the oxidizing agent: nitrogen Which element is the reducing agent: calcium