化學
化學反應、化學計量、分子結構與元素性質。
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which product, according to fda labeling, is raw, unprocessed, contains…
fresh tomatoes
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iclicker question 1 (3 mins) draw the lewis structure of ch₂cl₂ to assi…
B. $CH_2Cl_2$ has a tetrahedral shape and is polar.
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practice: physical vs. chemical part 1: classify the following properti…
1. P 2. C 3. P 4. P 5. P 6. P 7. C 8. P 9. C 10. C 11. C 12. P 13. P 14. C 15. C 16. P 17. P 18. P 19. P 20. P
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is this statement true or false? a manufacturer can advertise \made wit…
true
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what type of reaction is characterized by the formation of a single pro…
A. Synthesis
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which type of reaction is the opposite of a synthesis reaction? a. deco…
a. Decomposition
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13) a ph is a logarithmic scale that is used to describe the relative c…
13) B. False 14) A. True 15) 1.63 16) 1.30
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when sodium chloride reacts with silver nitrate, what are the products?…
B. Sodium nitrate and silver chloride
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practice: classification part 1: classify the following as a substance …
22. E. Element 23. E. Element 24. HE. Heterogeneous mixture 25. C. Compound 26. E. Element 27. C. Compound 28. HE. Heterogeneous mixture 29. C. Compound 30. E. Mixture of elements…
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8) alkaline means the same thing as... (a) acidic (b) neutral (c) ph (d…
8. D. basic 9. D. 14 10. D. neutralization 11. D. baking soda with a pH value of 8 - 9 (assuming option D was baking soda as the description was cut off but based on context)
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what are the products of the decomposition of water? a. water and oxyge…
B. Hydrogen and oxygen
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imagine that youve been instructed to complete the following steps to c…
| Step | Physical Change | Chemical Change | | ---- | ---- | ---- | | Step 1 | √ | | | Step 2 | √ | | | Step 3 | | √ | | Step 4 | | √ |
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choose the correct group of words as the appositive phrase. * 1 point 1…
16. b. my dog 17. b. a first edition 18. b. an organic mix
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identify a physical change and a chemical change that occurs when using…
A. A chemical change occurs when a wax candle burns, producing a flame. D. A physical change occurs when a candle's flame causes the wax to melt.
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which of the following is not an example of real - world applications o…
B. Melting of ice
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question 10. which of the following statements are true regarding the r…
Energy is always involved when physical or chemical changes occur. Heat can provide enough energy to cause both physical changes (such as melting) and chemical changes (such as th…
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23) an indicator is a substance that changes color when in contact with…
23) True 24) C. pure water 25) A. acidic
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21) what might happen if acidic chemicals were emitted into the air by …
21) Acid - rain can form, damaging plants, soil, buildings, and harming wildlife and human health. 22) 7
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complete the table. > get help here | | physical change | chemical chan…
| Statement | Physical Change | Chemical Change | |--|--|--| | Plants absorb nitrogen compounds through their roots | | O | | Death and decay of animals and plants return nitrogen…
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19) what might happen if you mixed a strong acid with an equally strong…
1. D. you would have a pH - neutral substance 2. D. our blood and other body fluids might become too acidic or basic
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question 8. examine the provided diagram, which illustrates the changes…
- Solid to liquid arrow: Melting - Liquid to solid arrow: Freezing - Liquid to gas arrow: Boiling - Gas to liquid arrow: Condensation - Solid to gas arrow: Sublimation - Gas to so…
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question 7. the diagram below shows the changes in the state of water (…
Freezing
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question 5. complete the table below. physical state definite shape? de…
| Physical State | Definite Shape? | Definite Volume? | Easily Compressed? | | ---- | ---- | ---- | ---- | | Gas | No | No | Yes | | Liquid | No | Yes | No | | Solid | Yes | Yes |…
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valence electrons noble - gas configurations are useful because they he…
Elements above and below each other in the periodic table have similar physical and chemical properties because they have the same number of valence electrons, which largely deter…
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writing noble gas configurations how do you simplify electron configura…
\([Kr]5s^{2}\)
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30 using a periodic table, write the full electron configuration of bro…
$1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{10}4s^{2}4p^{5}$
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sat prep 2 fill in the blank water can ______________ many substances, …
B. dissolve
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which of the following is a heterogenous mixture? 22/50 salt water stee…
Soil
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this picture represents which of the following? compound element mixtur…
C. mixture
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an element is a ___ that cannot be separated into simpler substances by…
pure substance
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what poetic element is most effective in showing the speaker’s admirati…
A. Imagery
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29 ccc patterns what element has an electron configuration of 1s²2s²2p⁶…
The element is calcium (Ca) and it is in the s - block.
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label the water molecule with element and charge.
For the larger red sphere: Oxygen, - For each of the two smaller teal spheres: Hydrogen, +
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chapter 2: science, matter, energy, and systems scientific method - sci…
- Science is about observing things, asking questions, and trying to understand causes. Scientists use three main tools: 1. Observation 2. Measurement 3. Experimentation - Scienti…
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the density of carbon dioxide is 0.0198 grams per cubic centimeter. how…
C. $1.98\times10^{-2}$
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step 2 fill in the subshells with the 8 electrons. list the subshells i…
$1s^{2}2s^{2}2p^{4}$
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23. which of the following molecules is a classic example of resonance?…
B. Benzene ($C_6H_6$)
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19. which of the following molecules has a trigonal pyramidal shape? a.…
B. Ammonia ($NH_3$)
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15. why do metals typically have lower electronegativity compared to no…
C. Metals lose electrons easily.
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11. which molecule is associated with sp hybridization and has a linear…
d. Acetylene ($C_2H_2$)
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6 a.m. - 30 psi 9 a.m. - 32 psi 1 p.m. - 35 psi amy measured the tire p…
A. The air molecules heated inside the tire causing them to move faster exerting more pressure on the inside walls of the tires.
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what does the law of conservation of matter state? matter is the cause …
Matter cannot be created or destroyed.
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identify all pictures that show a physical change
A. The picture of the paper - shredding machine, B. The picture of the hammer hitting a nail, C. The picture of the bruised pear
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a scientist uses an instrument to observe the pattern of molecules in a…
D. solid
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the molecules that make up a plastic two - liter bottle a are in consta…
A. are in constant, rapid, random motion.
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the group of nobel gasses are located where on the periodic table? top …
D. Right
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which of the following is not an example of a physical science? a. chem…
B. Economics
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the diagram below shows a portion of a graduated cylinder. what is the …
B. 24 mL
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there is a law that explains that matter cannot be created nor destroye…
Law of Conservation of Matter
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jared investigated chemical reactions based on smell, color change, and…
A. An observation
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3. which molecule is an example of sp³ hybridization? a. ethene (c₂h₄) …
B. Methane ($CH_4$)
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timothy plays basketball in his driveway during the summer. by accident…
A. slower, low
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josie investigated chemical and physical changes using eggs. she did th…
B. Cracked
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in the periodic table, horizontal rows are called and vertical columns …
Periods; Groups
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the diagram below represents a phase change for some copper atoms. whic…
C. solid to liquid
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as we stand and watch the hot air balloon rise in the sky, we can imagi…
A. moving faster and spreading apart
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of protons, neutrons, and electrons of the stable boron shown above. pr…
Protons: 5 Neutrons: 6 Electrons: 5
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the density of carbon dioxide is 0.0198 grams per cubic centimeter. how…
C. $1.98\times10^{-2}$
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what is the atomic number of an atom? the row of the periodic table to …
The number of protons it contains
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use the drop - down menus to select the correct structural elements. a …
1. Stanza 2. Sentence 3. Rhyme - scheme 4. Meter
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3. the atomic mass for zn is given as 65.39 amu. explain why there is n…
The atomic mass of Zn (65.39 amu) is a weighted - average of its isotopes' masses, not the mass of a single atom. Each isotope has a mass close to a whole number.
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the subatomic particle to its charge proton neutron electron
Proton - + Neutron - 0 Electron - -
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which of the following would a sociologist argue largely influences hum…
B. Social forces
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question 4 of 22 complete each statement with the correct term. blank s…
$C_4H_5N_2O$, $C_8H_{10}N_4O_2$
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i claim that a phase change is a ______ change because ______ evidence …
Afirmación: Afirmo que un cambio de fase es un cambio físico porque solo altera la forma física del material, no su composición química. Evidencia: Mi evidencia es que cuando el h…
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sentence starters claim, evidence, reasoning claim i claim that a phase…
I claim that a phase change is a physical change because no new chemical substances are formed. My evidence is that when ice melts, the substance is still water.
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sentence starters claim, evidence, reasoning claim i claim that a phase…
# Explicación paso a paso: ## Paso 1: Definir tipo de cambio Un cambio de fase es un cambio físico porque solo afecta a las propiedades físicas de una sustancia, como su estado (s…
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5. write the formulas for the following compounds: (a) sodium iodide (b…
(a) $NaI$ (b) $BeF_2$ (c) $MgO$ (d) $Al_2S_3$
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which of the following is not evidence of a chemical reaction? color ch…
melting
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which of the following is a pure substance? gun powder soda sugar water…
steam
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topic 2 assessment 28 of 30 19:42 / 40:00 which of the following is a v…
D. steam
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in table 3.5, why are the mass ratios of copper to chlorine not the sam…
the two compounds are not the same
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3. write the formulas for the following compounds: (a) sodium iodide (b…
a. $NaI$ b. $BeF_2$ c. $MgO$ d. $Al_2S_3$
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which is true about burning fossil fuels? most fuels contain a high per…
most fuels contain a high percentage of carbon
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warm up – sept 17th orbital notation and % yield 1s 2s 2p 3s 3p ↑↓ ↑↓ ↑…
1. Electron configuration: $1s^{2}2s^{2}2p^{6}3s^{2}3p^{3}$ Orbital notation: 1s: $\boxed{\uparrow\downarrow}$, 2s: $\boxed{\uparrow\downarrow}$, 2p: $\boxed{\uparrow\downarrow}\b…
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which of the following is a chemical change? melting butter igniting a …
igniting a gas fire
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________ is a separation technique that produces highly pure solids. fi…
crystallization
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assuming that the coal was 2 90 % sulfur by mass and that combustion wa…
If the mass of coal burned is \(m_{coal}\) tons, the mass of \(SO_2\) produced is \(0.058m_{coal}\) tons. If we assume \(m_{coal}=1\) ton, the answer is \(0.058\) tons.
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part four - prevent injury in the shop develop a safety contract with s…
1. Exposure to heavy - machinery, chemicals, and strenuous labor. 2. Cuts, fractures, burns. 3. Wear PPE, follow safety procedures, maintain equipment.
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a heterogeneous mixture is poured through a piece of filter paper that …
solution
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topic 2 assessment 21 of 30 14:47 / 40:00 consider the table above. in …
6.50 grams
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2. draw a bohr diagram to show the electron transfer that occurs when m…
A Bohr diagram should be drawn as described above, showing a magnesium ion with a 2+ charge and two fluoride ions each with a 1 - charge, indicating the electron - transfer from m…
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17 quelle est la masse de chacun des échantillons suivants? a) 0,25 mol…
b) $336,59\ g$ c) $98,07\ g$ d) $854,395\ g$
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1. what element is located in a. group 2, period 5? b. group 16, period…
1a. Strontium (Sr) 1b. Selenium (Se) 1c. Boron (B) 1d. Niobium (Nb) 2. Francium (France), Germanium (Germany), Polonium (Poland) 3. Curium (Marie and Pierre Curie), Einsteinium (A…
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part e - critical thinking 21. a cold pack becomes icy after being sque…
21. Endothermic. Heat is absorbed as the pack becomes cold. 22. Sink. Density of aluminum is $2.7\ g/cm^{3}$ which is greater than water's density of $1\ g/cm^{3}$. 23. Synthesis …
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24. a rock dropped in a graduated cylinder raises the level of water fr…
$3\mathrm{g/cm}^3$
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part d - balancing practice balance each equation: 16. h₂ + cl₂ → hcl 1…
16. $H_2+Cl_2 = 2HCl$ 17. $4K + O_2=2K_2O$ 18. $CaCO_3 = CaO+CO_2$ 19. $Zn + 2HCl=ZnCl_2 + H_2$ 20. $2C_2H_6 + 7O_2=4CO_2+6H_2O$
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daily activator: periodic table practice 1. tell which element is locat…
1. a. Hydrogen b. Zirconium c. Beryllium d. Tungsten e. None f. Tin g. Zinc h. Francium i. Polonium j. Chlorine k. Silver l. Vanadium m. Platinum n. Aluminum 2. a. NM b. M c. M d.…
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exprime chacune des quantités suivantes en moles. a) 32 g de carbone. b…
a. $\frac{8}{3}\ mol\approx2.67\ mol$ b. $\approx12.69\ mol$ c. $\approx1.99\ mol$ d. $\approx0.88\ mol$ Oui, ils ont raison.
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5. what does \endothermic\ mean in terms of energy flow?
An endothermic process means the system absorbs energy (usually heat) from the surroundings.
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4. define neutralization reaction and give a real - life example.
A neutralization reaction is a chemical reaction between an acid and a base to form a salt and water. A real - life example is the use of antacids to neutralize stomach acid.
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14 - 18. list the substances a - e in order from most dense to least de…
Substance B, Substance A, Substance E, Substance D, Substance C
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part b - multiple choice 6. which subatomic particle determines the ide…
6. a) Proton 7. c) Neon (Ne) 8. c) Produces OH⁻ ions in solution 9. b) N₂ + 3H₂ → 2NH₃ 10. b) Melting ice
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16 combien y a - t - il datomes dans 19,0 mol deau (h2o)? réponse: 17 q…
1. **Question 16: Calcul du nombre d'atomes dans 19,0 mol d'eau ($H_2O$)** - # Explanation: - ## Step1: Savoir le nombre d'atomes par molécule d'eau - Une molécule d'eau ($H_2O$) …
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une technicienne spécialiste de la qualité de lair a détecté 0,020 mg d…
La quantité de contaminants détectée ne présente pas de danger pour la santé humaine.
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4. strontium consists of four isotopes with masses of 84 (abundance 0.5…
87.712
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3. naturally occurring europium (eu) consists of two isotopes was a mas…
$152.04$
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when solid ice cream becomes a liquid, what happens to the particles? t…
The particles gain energy and move faster.
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2. complete the following chart: isotope name atomic # mass # # of prot…
| Isotope name | atomic # | mass # | # of protons | # of neutrons | # of electrons | | ---- | ---- | ---- | ---- | ---- | ---- | | 92 uranium - 235 | 92 | 235 | 92 | 143 | 92 | | …
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refer to the illustration. molecules like molecule 1 are found in * 0/1…
D. carbohydrates