化学
化学反应、化学计量、分子结构与元素性质。
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what is/are the carbonyl product(s) formed when the alcohol below is ox…
The third option (the ketone structure)
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which statement concerning the compound shown below is incorrect? it is…
It can be oxidized to give a ketone.
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what is the structure of 1 - chloro - 3 - ethyl - 2 - heptanol?
The first and the third structures (assuming they are drawn correctly with the - OH on C - 2, Cl on C - 1 and ethyl on C - 3) are correct representations of 1 - chloro - 3 - ethyl…
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what is the structure of 1,1,2 - trichloroethane? question 12 (10 point…
The first structure
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what product is formed when ch₃ch₂ch₂ch₂ - sh is oxidized? ch₃ch₂ch₂ch …
$CH_3CH_2CH_2CH_2 - S - S - CH_2CH_2CH_2CH_3$
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which compound has the highest boiling point? ch3(ch2)4ch2oh ch3(ch2)2o…
$CH_3(CH_2)_4CH_2OH$
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35 multiple choice 6.15 points what is the age of the 1st chemical evid…
3.5 Billion Years
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when a primary alcohol is oxidized, the initial organic product is a/an…
B. aldehyde; carboxylic acid
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what alcohol would be oxidized to form the compound below? ch3 - c(ch3)…
The second option (the alcohol with the structure $CH_3 - C(CH_3)(CH_2CH_2CH_3)-CH_2OH$)
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what is the iupac name of the compound below? 3,6 - diethyl - 3 - methy…
3,6 - diethyl - 3 - methyl - 8 - decanethiol
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which is a secondary alcohol? h—o—c—o—h h h h h h—c—c—c—c—o—h h h h h c…
The fourth - option structure (with - OH on a C bonded to two other C - atoms) is a secondary alcohol.
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which is an example of an ether? none of these structures is an ether.
The fourth structure (the cyclic structure with an oxygen atom in the ring)
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section 3.4 elements and compounds in your textbook, read about element…
1. c. element 2. b. compound 3. d. oxygen 4. c. aspirin 5. d. periods 6. b. groups or families 7. element 8. compound 9. element 10. element 11. compound 12. Ne 13. Ca 14. Fe 15. …
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section 3.3 mixtures of matter in your textbook, read about pure substa…
1. mixtures 2. pure substances 3. heterogeneous 4. sand - water mixture 5. solutions 6. salt - water mixture 7. b. distillation 8. c. crystallization 9. d. chromatography 10. a. f…
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section 3.2 changes in matter in your textbook, read about physical cha…
Physical Change: boil, condense, crumple, crush, freeze, grind, melt, vaporize Chemical Change: burn, corrode, ferment, oxidize, explode, rot, rust, tarnish 17. c. products 18. a.…
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during the persian invasion of greece in 480 b.c.e., themistocles persu…
E. abandon the city of Athens and let the Persians burn it.
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quiz: nucleic acids and lipids what factor determines how much linoleic…
B. The length of the carbon - carbon double bonds
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which of the following shows an unsaturated fatty acid? a. chemical str…
C.
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question 8 of 10 which of the following is an organic molecule? a. oxyg…
B. Sucrose
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section 3.1 properties of matter in your textbook, read about physical …
(1) mass (2) substance (3) properties (4) physical (5) density (6) chemical
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question 4 of 11 what are large molecules made up of smaller molec- a. …
C. Atoms
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5.85×10^{23} atoms → grams
If the molar - mass of the element is $M\text{ g/mol}$, the mass is $\frac{5.85}{6.022}M\text{ g}\approx0.971M\text{ g}$
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understanding concepts 1. explain how a physical change differs from a …
1. A physical change doesn't change the substance's chemical composition, while a chemical change forms a new substance. 2. (a) Chemical change; bacteria break down organic matter…
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question 10 of 10 what happens when a lithium ion is attracted to a flu…
D. They form an ionic compound.
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question 9 of 10 which produces an ionic bond? a. creating an electrost…
A. Creating an electrostatic attraction
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question 8 of 10 which best explains how the human body obtains energy …
A. By breaking and reforming chemical bonds
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question 7 of 10 methane gas is burned to provide heat. the chemical re…
A. CO₂ + 2H₂O + energy
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question 6 of 10 look at the picture below. which best describes the bo…
D. A covalent bond between two atoms
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question 5 of 10 water reacts with sodium metal to produce sodium hydro…
B. Sodium metal and water
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question 4 of 10 why is carbon important for forming complicated molecu…
B. It can form four covalent bonds.
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what happens when an atom gains an electron? a. it has an increase in t…
B. It becomes a negative ion.
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which of these is an example of a chemical change? a. dissolving salt i…
D. Setting a piece of paper on fire
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which will form an ionic bond? a. two oxygen atoms b. any two neutral a…
C. Two oppositely - charged ions
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what is all matter made of? a. liquids b. carbon c. atoms d. molecules
C. Atoms
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question 8 of 10. which two elements make up the most common compound? …
D. H and O
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question 4 of 10 the picture below represents an atom of the element. h…
A. 5
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question 2 of 10 which statement is true about nitrogen and oxygen? a. …
D. They are both made of protons, neutrons, and electrons.
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question 1 of 10 the picture below represents an oxygen atom. how many …
D. 8
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1. the density of ice at 0 °c is 0.9168 g ml⁻¹, and that of liquid wate…
The volume of 1.000 g of ice at 0°C is approximately 1.091 mL and the volume of 1.000 g of water at 0°C is approximately 1.000 mL.
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4. choose the example below that exhibits proper use of slang in formal…
"My family's finally gonna go on vacation this summer," she giggled.
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question 36 1 pts give the ground state electron configuration for mg²⁺…
$1s^{2}2s^{2}2p^{6}$
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the ground - state electron configuration of sc is none of the above 1s…
$1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{1}$ ### Question 2
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question 26 1 pts there are ______ orbitals in the third shell. 9 25 16…
Question 26: A. 9 Question 27: C. As
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in the quantum mechanical model of the atom, electrons travel in circul…
Question 1: electron energies are quantized Question 2: principal
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which electron configuration represents a violation of hunds rule for a…
The electron configuration with 1s $\uparrow\downarrow$, 2s $\uparrow\downarrow$, 2p $\uparrow\downarrow$ $\square$ $\square$ represents a violation of Hund's rule.
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the ground - state electron configuration of the element ____ is kr5s^1…
C. Mo
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which one of the following is the correct electron configuration for a …
Question 1: First option (1s box with two electrons of opposite spins, 2s box with two electrons of opposite spins, 2p boxes with three unpaired electrons of same spin) Question 2…
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an atom of $^{118}$xe contains ______ neutrons. 54 172 64 110 118 quest…
First question: C. 64 Second question: A. 3+
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how many total electrons are in the o2- ion? 18 9 10 16 8 question 18 1…
1. C. 10 2. D. chlorine
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geraldos science teacher mixed liquid x and liquid y, both at room - te…
A. A chemical reaction produced a new substance
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question 15 1 pts the nucleus of an atom contains electrons protons and…
Question 15: C. protons and neutrons Question 16: B. groups
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hydrogen gas (h₂) and oxygen gas (o₂) react to form liquid hydrogen per…
A. The atoms of the reactants have combined to form a new substance.
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a safety data sheet (sds) includes information on the properties of a c…
Physical and health hazards
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question 13 1 pts elements in group 8a are known as the ________. chalc…
Question 13: E. noble gases Question 14: D. metal, nonmetal
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when a small piece of white marble rock is carefully placed in a beaker…
B. The rock reacted with the acid and made a new gaseous substance
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question 11 an element in the upper right corner of the periodic table …
Question 11: is definitely a nonmetal Question 12: $^{128}_{52}Te^{2 - }$
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question 9 1 pts isotopes are atoms that have the same ______ but diffe…
Question 9: C. atomic numbers, mass numbers Question 10: E. in the same group of the periodic table
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four preparations involving table sugar (sucrose) are described below. …
D. the color change that takes place after heat melts and begins to decompose the sugar
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michael mixes two chemicals together in a beaker. the chemicals change …
A. A chemical change occurred
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iron (fe) and diatomic oxygen (o₂) combine to produce iron(iii) oxide (…
C. A chemical reaction occurred because iron(III) oxide has different properties than iron and diatomic oxygen.
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question 7 1 pts all atoms of a given element have the same number of n…
Question 7: number of protons Question 8: 118, 79, 79
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a scientist has samples of both nitrogen (n₂) and hydrogen (h₂). both o…
B. A new compound formed when nitrogen and hydrogen chemically reacted.
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when iron is burned, it combines with oxygen to form iron oxide. the ta…
C. A chemical reaction occurs because the density of iron is different from the density of iron oxide.
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a chemist who studies water samples did a demonstration of how to test …
B. It is a new substance with different properties.
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a scientist had two substances. one was a yellow liquid. the other was …
D. A new substance with properties different from either of the liquids was formed.
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during some types of changes, new materials with different characterist…
C. burning
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question 5 the density of silver is 10.5 g/cm³. a piece of silver with …
9.62 ### Question 6
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lab safety quiz 0:14:51 elapsed question 7 (1 point) if a substance in …
Question 7: B. False Question 8: A. True
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micah dropped an effervescent tablet into a glass of water. the tablet …
A. A new substance was formed when the tablet was dropped into the water.
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7. two solutions are added together and the new solution becomes hot. t…
C. a chemical change is taking place
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when solid baking soda mixes with liquid vinegar, the mixture starts to…
B. It is very different from the baking soda and vinegar.
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5. sarah is making a strawberry banana smoothie. she combines one banan…
C. The substances did not change.
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question 1 the temperature of 25°c is ____ in kelvins. 103 298 166 248 …
Question 1: B. 298 Question 2: D. 71.2
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directions: select each correct answer. marco is about to combine a red…
Purple liquid with gas bubbles, Green liquid, Purple liquid with condensation
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question 35 1 pts which of the following is the shorthand electron conf…
[Ar] 4s² 3d⁶
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question 33 1 pts which ion with a +2 charge has the electron configura…
Question 33: Sr²⁺ Question 34: P³⁻
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11 choose the example of appropriate use of repetitive information belo…
"Sunday, Sunday, Sunday! Our biggest furniture sale begins Sunday!"
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select the sentence with a sensory detail that describes a sound. jack …
Then a growing din of shouting and chanting caught his ear.
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question 19 1 pts why is water called the \universal solvent\? water ha…
Because water has polar bonds that let it pull apart many other molecules.
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question 4 10 pts when a gas is compressed, its ____________ increases …
temperature
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when using the periodic table the element name always matches the lette…
1. False 2. True 3. Gaining or losing electrons
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when you add neutrons to an element it changes the charge of the elemen…
1. B. False 2. B. Elements with a different number of neutrons 3. B. Carbon 12, 13, 14
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electrons are found in the cloud shell orbit all of the above the atomi…
1. D. All of the above 2. A. Equal to the protons in the nucleus of an atom
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atomic mass is the number of electrons in the nucleus the number of pro…
The sum of protons and neutrons in the nucleus To attract electrons while forming a chemical bond
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08 question (3 points) name the following compounds. 1st attempt part 1…
Part 1: Tetraphosphorus decoxide Part 2: Carbon monoxide Part 3: Arsenic trifluoride
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07 question (4 points) launch tutorial lesson open - book section 2.7 g…
Part 1: magnesium perchlorate Part 2: ammonium nitrate Part 3: copper(II) acetate Part 4: potassium sulfite
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what is the mass number?
# Explicación: ## Paso 1: Identificar partículas en el núcleo El número de masa es la suma del número de protones y neutrones en el núcleo de un átomo. En la imagen, vemos 2 partí…
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protons: 9 neutrons: 10 electrons: 9 what is the mass number?
19
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protons: 9 neutrons: 10 electrons: 9 what is the mass number?
19
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for each atom, determine what process it will undergo when becoming a s…
K: Lose 1 Electron Al: Lose 3 Electrons O: Gain 2 Electrons Ca: Lose 2 Electrons Cl: Gain 1 Electron
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part 2 remember the standard format for writing the formula of an ionic…
When forming a monatomic ion, K will lose 1 electron(s), while S will gain 2 electron(s). The formula for potassium sulfide is $K_{2}S$.
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determine the type of bond that will form between each listed pair or w…
Ca and Br: Ionic Bond Cu and Zn: Metallic Bond Mg and S: Ionic Bond S and Cl: Covalent Bond N and O: Covalent Bond Cr: Metallic Bond Fe and nitrate: Ionic Bond
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the element boron has two stable isotopes: boron - 10 (10.0129 u) and b…
Part 1: 19.9 Part 2: 80.1
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10. ice floats! so what? consider what would happen if ponds and other …
10. Ice floating provides insulation, protecting aquatic life. If it sank, bodies of water would freeze from bottom - up, harming life. 11. Ice floats as it is less dense than liq…
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question 31 ____ are unloaded into the synapse by neurons, whereas ____…
D. Neurotransmitters; hormones
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question 6 which of these describes a polymer? a molecule with a polar …
a large molecule made of smaller subunits
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the model shows water molecules interacting. the red circles represent …
Oxygen atoms in water molecules are also attracted to hydrogen atoms in other water molecules.
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part a completion use this completion exercise to check your understand…
1. density 2. intensive 3. type 4. ST 5. AT
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in the table below you will find three descriptions of scientists engag…
1. hypothesis 2. experiment 3. theory
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read the descriptions below of two substances and an experiment on each…
Sample A: mixture Sample B: pure substance