Chemistry
Chemical reactions, stoichiometry, molecular structures, and element properties.
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1. calculate the average atomic mass of oxygen using the information in…
$15.9999$ amu
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5. from the picture below, what are true options (select two) for the i…
The isotopes have same number of Protons and neutrons. The isotopes have same "Z" but different "A"
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explain why each of the following examples are not physical changes (yo…
1. Digestion of food: It is a chemical change due to enzyme - catalyzed reactions altering food's chemical makeup. 2. Sour milk: It is a chemical change as bacteria cause lactose …
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4. calculate the average atomic mass of hydrogen with the following iso…
1.012 amu
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3. an atom of an element \a\ have equal percentage of isotopes, a - 50 …
51 amu
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1. what are different about the isotopes carbon - 12, carbon - 13 and c…
The isotopes have different atomic mass. The isotopes have different number of neutrons.
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5. what are valence electrons? the electrons in the innermost electron …
The electrons in the outermost electron shell of the electron cloud
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2. which is the correct electron - dot symbol for a boron atom in the g…
The electron - dot symbol with the B symbol and 3 dots around it is the correct one. Without seeing the full options clearly, the correct option should be the one with the symbol …
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1. which electron configuration is correct for a sodium ion? 2-7 2-8-1 …
2 - 8
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2. an element has a fixed composition because it contains only one type…
2. atom 3. homogeneous 4. metal 5. - 210; - 195.8 6. Evaporation (or distillation) 7. physical 8. Chemical 9. precipitate 10. gas 1. The properties of a compound are different fro…
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the amount of a sample remaining after t days is given by the equation …
74 days
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the equation for the ph of a substance is ph = - log h+, where h+ is th…
$[H^{+}]=10^{-7.2}$
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c. silicon dioxide d. sand 6. a mixture that appears to contain only on…
6. a. homogeneous mixture 7. b. size of largest particles 8. d. gold 9. a. water 10. b. durability, flexibility Section 2, Question 1: substance
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name: ______________ class: ______________ date: ______________ use you…
1. b. compounds 2. c. element 3. b. Al 4. d. compound 5. (Incomplete options provided, but carbon dioxide and silicon are not mixtures as they are a compound and an element respec…
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the equation for the ph of a substance is ph = - logh⁺, where h⁺ is the…
3.3
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after reading the infographic, put the stages of the circular process i…
1. New products are created, including plastics. 2. The chemical’s are sold to customers. 3. Plastic waste is collected. 4. The plastic is sorted. 5. The plastic waste is heated. …
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part 2: critical thinking 6. why does the film argue that food labels c…
6. d 7. c 8. a 9. c 10. b
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exit ticket 9 (module 2 - lesson 7) question 2. which of the following …
Fluorine, chlorine, bromine, and iodine.
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question 3. a scientist is developing a new lightweight battery and nee…
Element name: Lithium Element symbol: Li
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env.10 - which of the following is an example of nonpoint - source poll…
1. rain washing salt off the roads 2. excessive use of fertilizers on farms 3. Cannot be answered without the map.
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chemical properties of matter – understanding how substances react sect…
1. A characteristic of a substance shown during a chemical reaction where it becomes a different substance. 2. Physical properties can be observed without changing the substance's…
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question 3. a student has a dried spot of purple ink that contains a mi…
Part A: The blue dye is more soluble than the red dye. Part B: The blue dye will move further up the paper strip than the red dye. Part C: Yes, chromatography can be used effectiv…
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question 3. a student has a dried spot of purple ink that contains a mi…
The blue dye will travel further than the red dye.
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question 3. a student has a dried spot of purple ink that contains a mi…
Part A: Blue dye Part B: The blue dye will move further up the paper strip than the red dye. Part C: Yes
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question 2. a student has a mixture of sand and salt, whose properties …
The sand will be filtered out
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question 2. a student has a mixture of sand and salt, whose properties …
Part A: The salt will dissolve in water and the sand will remain as a solid in the water. Part B: The sand will be retained on the filter paper as a residue and the salt - water s…
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question 1. a student has a mixture of ethanol (a type of alcohol) and …
Part A: Water Part B: Ethanol will vaporize first. Part C: Yes
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which of these are examples of chemical changes? check all that apply. …
burning a candle, frying an egg
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which of these are examples of physical changes? check all that apply. …
- freezing water - cutting paper - mixing water and acetone
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choose the correct description for each of the properties below: densit…
density: physical property flammability: chemical property solubility in water: physical property reactivity with water: chemical property melting point: physical property color: …
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question 6 0.5 pts which of these elements is classified as a nonmetal?…
Phosphorus (P)
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what do these two changes have in common? making jam an engine using ga…
Both are chemical changes, Both are caused by heating
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what do these two changes have in common? adding dish soap to water in …
Both are only physical changes. Both conserve mass.
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what do these two changes have in common? melting wax snowflakes formin…
Both are changes of state.
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what rule/ principle states that electrons in the same sublevel (p, d, …
B. Hund's rule
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what do these two changes have in common? picking up a paper clip with …
Both conserve mass, Both are only physical changes
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what rule/principle states that electrons fill orbitals from lowest ene…
Aufbau principle
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what do these two changes have in common? mixing chocolate syrup into m…
Both conserve mass.
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what do these two changes have in common? sanding a piece of wood stapl…
Both are only physical changes.
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what do these two changes have in common? a piece of pear turning brown…
Both are chemical changes.
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what do these two changes have in common? crushing a mineral into powde…
Both are only physical changes.
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what do these two changes have in common? a piece of pizza rotting in a…
Both are chemical changes.
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what do these two changes have in common? ice crystals forming on a win…
Both are only physical changes.
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identify one advantage to each of the following models of electron conf…
- Dot structures: Show valence electrons easily. - Arrow and line diagrams: Illustrate electron - spin and orbital occupancy well. - Written electron configurations: Concisely rep…
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the electron configuration for aluminum (al) is shown below: 1s²2s²2p⁶3…
(Without seeing the full - details of the diagrams, assume we have a diagram that shows 2 electrons in the innermost shell, 8 electrons in the second shell, and 3 electrons in the…
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use the periodic to fill in the numbers in the electron configurations …
A = 2 B = 1
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which answer below correctly identifies the type of change and the expl…
physical change because even though a color change occured, each solid maintained its original properties, which could be seen as soon as the magnet was applied
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which diagram shows the correct electron configuration for fluorine (f)?
The first option (where 1s has 2 paired electrons, 2s has 2 paired electrons, and 2p has 5 electrons with one orbital having 2 paired electrons and the other two having 1 unpaired…
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question 7. a science student prepares a mixture of water and sand in a…
B. Decantation
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use the periodic table to answer the questions below. which diagram sho…
The second diagram (with two electrons in 1s, two electrons in 2s, and three unpaired electrons in 2p) shows the correct electron configuration for nitrogen.
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which answer below correctly identifies the type of change and the expl…
C. chemical change because gas was released along with a color change, which indicated that the copper(II) sulfate pentahydrate was transformed into a different substance
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question 1. a student is using a procedure to separate a mixture in the…
Part A. Distillation Part B. Boiling point Part C. It separates liquids that have different boiling points
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type in the maximum number of electrons that can be present in each she…
$n = 5$ shell: 50 $n = 2$ shell: 8 $n = 2$, $l = 0$ sub - shell: 2 $n = 2$, $l = 1$ sub - shell: 6 $3d$ sub - shell: 10 $2s$ sub - shell: 2 $5f$ sub - shell: 14
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match each set of quantum numbers to the correct subshell description b…
$2p:4$ $3d:2$ $2s:1$ $4f:5$ $1s:3$
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which answer below correctly identifies the type of change and the expl…
physical change because even though gas formation was observed, the water was undergoing a state change, which means that its original properties are preserved
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which of the following sets of quantum numbers describe valid orbitals?…
$n = 1,l = 0,m = 0$; $n = 3,l = 0,m = 0$; $n = 5,l = 4,m=-3$
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question 2. a student is using a procedure to separate a mixture in the…
Part A. Chromatography Part B. Solubility Part C. It separates mixtures based on different solubilities of substances in a given solvent.
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for the n = 3 electron shell, which of the following quantum numbers ar…
$l = 0$, $m=-2$, $m = 2$
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question 3. a student is using a procedure to separate a mixture in the…
Part A. Magnetic separation Part B. Magnetism Part C. It separates magnetic substances from nonmagnetic substances.
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question 4. a student is using a procedure to separate a mixture in the…
Part A: Decantation Part B: Solubility (insolubility of solids in the liquid) Part C: It separates insoluble solids from liquids
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question 3. a student is using a procedure to separate a mixture in the…
Part A: Magnetic separation Part B: Magnetic property Part C: Separates magnetic components from non - magnetic components in a mixture
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question 2. a student is using a procedure to separate a mixture in the…
Part A: Paper - chromatography Part B: Solubility and rate of movement in a solvent Part C: Separates a mixture into individual components
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which answer below correctly identifies the type of change and the expl…
C. chemical change because gas formation was observed, which indicated that the calcium carbonate was transformed into a different substance
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question 1. a student is using a procedure to separate a mixture in the…
Part A. Distillation Part B. Different boiling points Part C. Converts a liquid mixture into vapor by heating, condenses the vapor back into a liquid to separate components based …
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which answer below correctly identifies the type of change and the expl…
physical change because even though a particle size change was observed, the calcium carbonate retained its original properties and was not transformed into a new substance
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use the dot structure on the right and the periodic table to determine …
argon (Ar)
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use the electron configurations and the periodic table to answer the qu…
bromine (Br)
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use the electron configurations and the periodic table to answer the qu…
Nitrogen
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which of the following is the correct electron configuration for titani…
1s²2s²2p⁶3s²3p⁶4s²3d²
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21. what effect does an increase in temperature have on the density of …
21. An increase in temperature decreases the density of air because air molecules spread out (occupy more volume) while mass remains constant. 22 - a. A balance. 22 - b. 28 mL 22 …
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use the periodic table to answer the questions: which is the correct el…
1s²2s²2p⁶3s¹
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synthetic materials ○ have only negative effects on the environment ○ a…
have undergone chemical reactions
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unit 1: materials science. explain the common characteristics that all …
(1) Synthetic materials come from raw materials like petroleum, natural gas, or coal. (2) The process often involves chemical reactions such as polymerization. (3) They are create…
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which of these diagrams correctly shows the electron configuration for …
The third option (where there are two electrons in 3s and three electrons in 3p with one pair and one unpaired electron) is correct.
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1. what is a type of matter that cannot be separated into other substan…
1. b. Pure substance 2. c. Mixtures 3. d. Burning 4. c. Rusting 5. d. Gas production 6. c. Chemical reaction 7. b. Size change 8. b. Element
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34. which neurotransmitter is linked to movement and parkinsons disease…
34. A. Dopamine 35. B. Hormones 36. B. Pituitary 37. C. Adrenal 38. B. Anterior 39. B. Metabolism 40. A. Insulin and blood sugar 41. B. Slows down heartbeat 42. B. Relay signals b…
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look at the model of the helium atom shown below. what part of the atom…
A. electron
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why are atoms sometimes shown using models like the one in this picture…
C. because it is a convenient way to show the parts of an atom
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8 directions: select all the correct answers. in 1803, the british chem…
All atoms of the same element are exactly alike. Atoms are indivisible and indestructible particles.
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what is the correct representation for the subshell with n = 2 and l = …
16
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an atom of fluorine has the atomic number 9, and its mass number is 19.…
B. Y
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what is the correct representation for the subshell with n = 2 and l = …
The correct representation for the subshell with \(n = 2\) and \(l = 1\) is \(2p\). The number of subshells in the \(n = 4\) shell is 4.
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what is the correct representation for the subshell with n = 2 and l = …
2p
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an atom of fluorine has the atomic number 9, and its mass number is 19.…
We need to find the option that shows 9 protons, 9 electrons and 10 neutrons. Since the options are not shown in full, we assume that the correct option is the one that has these …
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the term element refers to atoms that have the same number of a. ions b…
A. protons
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isotopes are different forms of the same element. thus, isotopes always…
A. protons, neutrons
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4 an atoms mass number is composed of the total number of ______ contai…
B. protons and neutrons
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an atom has a charge of 1+. if the atoms nucleus contains 23 protons, t…
A. 22 electrons
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the diagram below represents a stable, uncharged lithium atom. it shows…
The diagram with 3 protons and 2 electrons shows a lithium ion. (Since the diagrams are not labeled, you would need to visually identify the one with 3 protons and 2 electrons amo…
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at one time, scientists thought that electrons orbited an atoms nucleus…
C. a region in which an electron will probably be
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which of the following is not a valid set of quantum numbers? n = 3, l …
The set $n = 3,l = 3,m = 3$ is not a valid set of quantum - numbers. The correct possible values of $l$ for $n = 4$ are $0,1,2,3$.
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14 - 18. a - e in order from most dense to least dense based on the fac…
B, A, E, D, C
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which type of emr is often used to very efficiently vibrate water molec…
microwaves
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identify the stages of injury and inflammation. injury inflammation inj…
A. Tissue injury resulting in the release of chemical signals B. Dilation and increased leakiness C. Phagocytosis and platelet - mediated clotting for repair
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maxim the only maxim i need to know is to treat others as i want to be …
The only maxim I need to know is to treat others as I want to be treated. We try to remember the maxim that "actions speak louder than words."
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write the number with scientific notation: -.07 × 10^(-8) 7 x 10^(-8) t…
-7.0 x 10^-10, Mrs. Gamma was reshelving books in the library.
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clue #5 whodunnit? write the number with scientific notation: 980,000 a…
For Clue #5: $9.8\times10^{5}$ For Clue #6: $7.4361\times10^{6}$
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4. how does the rhyme scheme of the poem contribute to the tone?
The rhyme scheme can create a musical quality, emphasize ideas or emotions, and through the repetition of sounds, draw attention to key words, all of which contribute to shaping t…
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lessler > quizzes > (quiz#2) smaw - electrode selection (2) smaw - elec…
welding position
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320 lec 12731 messier > quizzes (quiz#2) smaw - electrode selection a+ …
tensile strength