化学
化学反应、化学计量、分子结构与元素性质。
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what quantity are you given to start (number and unit)? □ 11.5 moles li…
11.5 moles Li
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what is oxygen □ homogeneous mixture □ heterogeneous mixture □ mixture …
element, pure substance
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what is carbon pure substance homogeneous mixture heterogeneous mixture…
element
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brass pure substance mixture element heterogeneous mixture homogeneous …
B. mixture, E. homogeneous mixture
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question 13 salt water element pure substance mixture homogeneous mixtu…
C. mixture D. homogeneous mixture
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what is magnesium citrate. mixture heterogeneous mixture pure substance…
# Breve explicación: La citrato de magnesio es una sustancia química formada por átomos de magnesio, carbono, oxígeno e hidrógeno en proporciones fijas. Un compuesto es una sustan…
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what is methane gas pure substance homogeneous mixture heterogeneous mi…
# Explicación breve: El gas metano tiene una fórmula química definida ($CH_4$), formada por átomos de carbono e hidrógeno en proporciones fijas. Un compuesto es una sustancia form…
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the molar mass is the conversion factor (1 mole li = 6.94 grams). what …
6.94 g
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what is charcoal + sand homogeneous mixture pure substance element comp…
# Explicación breve: La mezcla de carbón vegetal y arena no es un sustrato puro. No es un elemento ni un compuesto, ya que está formada por dos sustancias diferentes. Además, es h…
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what is sugar water □ homogeneous mixture □ compound □ pure substance □…
# Breve explicación: El agua de azúcar está formada por dos sustancias distintas (azúcar y agua), lo que la convierte en una mezcla. Además, el azúcar se disuelve uniformemente en…
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mr smith hypoventilates and retains too much co₂. which of the followin…
D. Peripheral chemoreceptors
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what is steel wool. homogeneous mixture mixture compound heterogeneous …
heterogeneous mixture
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razonamiento explique por qué su evidencia respalda su afirmación: • es…
- Esta evidencia apoya mi afirmación porque un cambio químico significa la formación de nuevas sustancias. - Un cambio químico forma nuevas sustancias con propiedades químicas dif…
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what is the sos pad □ homogeneous mixture □ mixture □ compound □ elemen…
heterogeneous mixture
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what type of substance is water compound element heterogeneous mixture …
compound, pure substance
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what is copper? homogeneous mixture mixture compound element pure subst…
# Breve explicación: El cobre es un elemento químico con el símbolo Cu y número atómico 29. Un elemento es una sustancia pura que está formada por un solo tipo de átomo. Además, l…
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what type of substance is salt pure substance homogeneous mixture heter…
compound
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what type of substance is baking soda □ homogeneous mixture □ element □…
compound
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what type of substance is sugar, pure substance element mixture heterog…
# Breve explicación: La azúcar es una sustancia formada por átomos de carbono, hidrógeno y oxígeno unidos químicamente en proporciones fijas. Un compuesto es una sustancia pura fo…
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what type of material is pond water heterogeneous mixture element homog…
# Breve explicación: El agua de un estanque no es una sustancia pura. Contiene partículas disueltas, organismos vivos y otros componentes. Un elemento es una sustancia que no pued…
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theoretical yield is the amount of product that would be obtained in an…
The blank should be filled with "ideal" as theoretical yield is based on a perfect or ideal - reaction scenario where there are no side - reactions, losses, etc.
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stoichiometry calculations often involve converting between moles and
mass (or grams)
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the process of adjusting reaction conditions to obtain the highest poss…
The statement is True.
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percent measures the efficiency of a chemical reaction.
yield
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the teen wanted to see how he might reduce the surface tension of water…
Accuracy in experimentation requires careful timing to ensure proper measurement.
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3. for each of the following isotopes, write the number of | | chromium…
| | Chromium - 58 | Chromium - 63 | |--|--|--| | # of $P+$ | 24 | 24 | | # of $e-$ | 24 | 24 | | # of $N$ | 34 | 39 |
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which electrons of an atom are most reactive? those that are the farthe…
those that are the farthest away from the positive atomic nucleus
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the groups of the periodic table are organized by the number of valence…
True
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1. here are three isotopes of an element: a. the element is: __________…
a. Carbon b. Mass numbers c. 6, 6 d. 6, 7 e. 6, 8
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39. chemical analysis of fossils can reveal: exact genetic sequences in…
Information about ancient atmospheric conditions
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multiple - choice question what property of carbon makes it so versatil…
It has 4 valence electrons
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which two elements are most likely ductile? a. c and p b. zn and n c. s…
D. Ag and Au
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17. complete the electron configuration for the following element: d. m…
[Ne]3s²
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matter 9. three students made multiple weighings of a copper - cylinder…
10a) PHY 10b) CHM 10c) CHM 10d) PHY 10e) PHY 10f) CHM 10g) PHY 10h) CHM 10i) PHY 11a) CHM 11b) CHM 11c) PHY 11d) CHM 11e) PHY 11f) PHY 11g) PHY 11h) CHM 11i) PHY 12) A. True 13) B…
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18. complete the noble gas notation for the following element: e. selen…
\([Ar]4s^{2}3d^{10}4p^{4}\)
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which group of elements contains the most reactive metals? a. metalloid…
B. alkali metals
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15. which process involves heat transfer from molecule to molecule? rad…
conduction
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14. why do dark - colored objects absorb radiant energy faster than lig…
None of the above options are correct.
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14. why do dark - colored objects absorb radiant energy faster than lig…
None of the provided options are correct.
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11. how many electrons can each sublevel hold? a. s- b. p- c. d- d. f- …
11. a. 2, b. 6, c. 10, d. 14 12. 2; opposite 13. ground 14. S 15. 20 17. \(1s^{2}2s^{2}2p^{6}3s^{2}\) 18. \([Ar]3d^{10}4s^{2}4p^{4}\)
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what statement is true about the eight elements on the periodic table t…
D. They have properties of both metals and nonmetals.
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which determines the identity of an element? a. number of energy levels…
C. number of protons inside the nucleus
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in an experiment, 16.0 g of so₂ is treated with 6.0 g of o₂. if so₃ is …
E. 15.0 g
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question 3 of 3 which of the following are forms that chemical hazards …
Mist, Gas, Liquid
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which of the following answer options are chemical hazards found on con…
Solvents, Asbestos, Silica, Lead, Flammable chemicals, Carbon monoxide, Hydrogen sulfide
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properties of four elements were determined and the location of each el…
C. Element Y
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6) examine the prefixes in model 2 below. fill in the numerical value t…
7) -ide 8) When there is one atom of the first element. 9) Phosphorus tribromide, Sulfur tetrachloride, Dinitrogen difluoride, Sulfur trioxide, Bromine monofluoride 10) $S_2F_{10}…
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atomic models and experiments quarter 1 study guide 1. look at the mode…
1. a) If it's Dalton's model, parts of his theory: atoms are indivisible, atoms of same element are identical, atoms combine in simple whole - number ratios, chemical reactions ar…
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unit 2 - lesson 22 modeling the valence of atoms element symbol valence…
| Element | Symbol | Valence Electrons | Ion Charge | | ---- | ---- | ---- | ---- | | Aluminum | Al | 3 | + 3 | | Sulfur | S | 6 | - 2 | | Calcium | Ca | 2 | + 2 |
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chemistry: exam 3 test review 1. what is the name of the group of eleme…
1. Noble gases 2. Alkali metals (metals) and halogens (non - metals) 3. The same number of electron shells 4. An electron in the outermost shell of an atom, involved in chemical b…
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use the quotation to answer questions 13 and 14. from this view of the …
D. It provided an effective system of representative government
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use the quotation to answer questions 13 and 14. from this view of the …
B. They wished to prevent the division of the country into rival political groups.
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sonnet i by gwendolyn bennett he came in silver armour, trimmed with bl…
1. Underline and bold "Death" and other relevant words like "sword", "armour" for dark - theme build - up. 2. Color - code the rhyme scheme according to the pattern ABAB CDCD EFEF…
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1. how does the principle of conservation of energy relate to chemical …
1. The total energy is conserved in chemical reactions, with energy converting between forms. 2. Activation energy is the minimum energy for reaction - initiating collisions and a…
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6) what is the significance of the maxwell - boltzmann distribution in …
## Question 6: B. It depicts the distribution of molecular speeds ## Question 7: C. Influencing the directionality and spontaneity of reactions ## Question 8: B. It explains behav…
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which among the following cancer treatment methods was devised by the e…
Nanocapsules
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instructions: for each one, read the question, highlight the answer, an…
1. B. Due to rearrangement and bonding changes of atoms 2. B. Energy is only transformed from one form to another 3. B. They provide an alternative pathway with a lower activation…
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naming ionic compounds practice worksheet name the following ionic comp…
1. ammonium chloride 2. iron(III) nitrate 3. titanium(III) bromide 4. copper(I) phosphide 5. tin(IV) selenide 6. gallium arsenide 7. lead(IV) sulfate 8. beryllium bicarbonate 9. s…
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which of the following is an acceptable set of quantum numbers to descr…
D. $n = 2$, $l = 1$, $m_l=-1$
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what is the ppt of a 500ml sample of water with 29 grams of dissolved s…
38 ppt (Note: This is an approximation - based selection as the calculated value is around 54.82 - 58 depending on the approximation method, and 38 ppt is the closest among the gi…
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what is the bond order of the s - o bonds in the following? a. 1.00 b. …
B. 1.33
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question #2 which set of observations is evidence that a chemical react…
Question #1: C. reactivity Question #2: C. reactivity
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fill - in - the blank questions: instructions: read the question and th…
1. conservation 2. electrostatic 3. activation 4. catalysts 5. molecular 6. electrons 7. thermodynamics 8. entropy 9. quantum 10. equilibrium
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10. a student kept a notebook during an investigation. which recorded o…
The color of two mixed solutions changed from clear to white.
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review the claim and the two pieces of evidence. chewing gum can improv…
Evidence B is stronger because it comes from a study with multiple participants, providing more objective and generalizable data compared to the anecdotal Evidence A which is base…
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when frozen carbon dioxide (co2) is heated, it changes directly into a …
Heat caused a change in state
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consider this claim: chewing gum can improve our alertness and lower ou…
Evidence B
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obsidian hydration dating (ohd), an artifact - dating technique that me…
B. composition, though:
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5. students performed an investigation on how aluminum cans taken to a …
B. a physical change because the material remains the same
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obsidian hydration dating (ohd), an artifact - dating technique that me…
B. composition, though:
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students observe a burning candle to study the changes in matter. which…
The burning wick and the melting wax are both types of physical and chemical changes.
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question 9 1 pts what chemical is the main component of natural gas? (w…
Methane
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what is another name for sodium hydroxide? (there are multiple answers …
Caustic soda
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2. a student added 10 ml of sodium chloride, nacl, to 100 ml of water a…
Sodium chloride is the solute, water is the solvent, and salt - water is the solution.
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1. a student dissolves sodium chloride, nacl, in distilled water. which…
solvent
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question 6 type the numerical value of zincs melting point (in degrees …
419.58
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type the numerical value of coppers melting point (in degrees celsius).…
1083
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what hazardous properties does sodium hydroxide have? (check all that a…
Corrosive. Can release dangerous amount of heat when dissolved in water. Can be fatal if ingested. Can cause blindness if it contacts your eyes.
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question 2 where is the hottest part of the bunsen burner flame? o with…
at the tip of the inner (bright blue) cone
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take quiz im not expecting you to know the answers - im not expecting y…
1. alloy 2. compound 3. element 4. mixture
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10. how many significant figures are in each of the following measureme…
10. a) 4 b) 6 c) 1 d) 3 11. a) 6.411 g b) 1.1 cm c) 2.79 m² d) 29.74 g/mL 12. $8.57\times10^{-8}$ m² 13. $2.22\times10^{-3}$ cm³ 14. c. volume 15. d. meter and kilogram 16. d. mm,…
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after sample a0106 was retrieved from the asteroid ryugu, a portion of …
A. the third extract in the sequence contains dimethyl sulfides and the fourth contains alkanes
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a new drug to combat acne has been developed from a compound that is fo…
D. biologists, chemists, and physicians
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dalton was an english schoolteacher, rutherford was a chemist from new …
the cumulative nature of science
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which of the models is an example of a solution?
The first model (the beaker with red liquid)
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what is the entire mixture of a lemonade drink called? a solution a sol…
a solution
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what is the sugar in lemonade? a solution a solvent a solute
a solute
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when you mix sugar into a glass of lemon juice until it disappears, the…
lemon juice
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when you mix salt into a glass of water until it disappears, the salt s…
salt
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when the first periodic table of the elements was published, the elemen…
New information changed the understanding of the atom's structure.
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in a solution, what is a solvent? a substance in which the solute disso…
A substance in which the solute dissolves.
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in a solution, what is a solute? the substance that clumps in the solve…
The substance that dissolves.
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what is a solution? a mixture where two fluids separator from one anoth…
A mixture where one substance dissolves evenly into another.
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choose the correct answer. what type of mixture is trail mix? solution …
heterogeneous
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choose the correct answer. which of these is not a mixture? hydrogen an…
hydrogen and oxygen combined to make a molecule of water
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choose the correct answer. which of the following shows an example of a…
The first image (the one with colorful objects)
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which of the following is a heterogenous mixture? ice cream sundae air …
ice cream sundae
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which of the following is an example of a homogeneous mixture? rocky ro…
tea
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choose the correct answer. is this ice cream sundae a homogeneous or he…
heterogeneous
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choose the correct answer. is this cookie a homogeneous or heterogeneou…
heterogeneous