Química
Reacciones químicas, estequiometría, estructuras moleculares y propiedades.
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choose the correct answer. is the freezing, melting, and evaporation of…
yes
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choose the correct answer. if a snowflake melted and then changed to a …
A. yes
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choose the correct answer. when a snowflake changes from a solid to a l…
yes
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part iv - atomic structure properties 1. build any atom you want with 1…
The atom built is Carbon (with 6 protons). ### Question 2
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prepwork part 1: directions: read the scenario below and answer the que…
Paper chromatography. It can separate the mixture of pigments in marker ink by using a solvent to carry the ink components up the paper; different pigments move at different rates…
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which of the following is a physical change? a burning b melting c rust…
b. melting
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question 7 chest pain associated with coronary artery disease is called…
C. angina.
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which example is a physical change? a rusting of a nail b burning of fu…
c. breaking of glass
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which type of color scheme does this chart show? monthly mean daily low…
b. Diverging color scheme
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which one among the following represents a physical change? a rusting o…
d. Melting of wax
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which of the following is an irreversible physical change? a melting a …
b. sharpening a pencil
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describing the purpose of a chemical... in your own words, describe the…
The purpose of a chemical equation is to represent a chemical reaction, showing reactants (substances reacting) and products (substances formed), their molar ratios (via coefficie…
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physical changes can be brought about by which of the following? select…
a. cutting, b. bending, c. dissolving
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part ii - building atoms of elements • build the following atoms of ele…
### First Row (Add 5 protons, 6 neutrons, 5 electrons) # Explanation: ## Step1: Determine protons The number of protons is given as 5, so \( p = 5 \). ## Step2: Determine neutrons…
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atomic structure practice o copying\ atomic # | symbol | element name |…
In the nucleus of the atom. ### b)
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how is a poem’s rhyme scheme marked and identified? ○ upper or lowercas…
A. upper or lowercase letters, such as "ABAB"
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crafting poetic verses alliterate anthem captivate communicate connect …
(for marking "RHYMING"): Mark the horizontal sequence of letters in the first row: R (column 2), H (column 3), Y (column 4), M (column 5), I (column 6), N (column 7), G (column 8).
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11. hoodoos are tall stru of sedimentary rock. both and help to create …
The processes that help create hoodoos are **erosion (specifically wind erosion and water erosion, often from rain/snowmelt)** and **weathering (like chemical weathering from mine…
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14. what is the first thing you should always do in lab? type a response
Put on appropriate personal protective equipment (PPE), such as safety goggles, lab coat, and gloves (or follow the specific safety protocols and instructions given by the lab sup…
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predict the products of this organic reaction: ch₂=c(ch₃)-c(=ch₂)-ch=ch…
The product of the catalytic hydrogenation reaction is \(\boldsymbol{\ce{CH3CH(CH3)CH2CH2CH2CH3}}\) (or 2 - methylhexane in IUPAC nomenclature, with the condensed structure as sho…
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while researching a topic, a student has taken the following notes: - r…
A. Dichloromethane, a hydrochlorocarbon, is composed of hydrogen, chlorine, and carbon; tetrafluorohexane, a perfluorocarbon, is composed of fluorine and carbon.
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the following (cyclohexane ring with double bond to ch₂) $xrightarrow{1…
The product \( \boldsymbol{A} \) is cyclohexylmethanol (structure: \( \ce{C6H11 - CH2 - OH} \)).
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day four: complex sentence punctuation exercise 7: punctuate complex se…
s (Exercise 7 Final Punctuated Sentences): 1. She had a habit of drawing beautiful flowers when she was bored. 2. Because so many boys always asked to go to the bathroom, Ms Brook…
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group a trial 1: 11.1 ml, trial 2: 12.4 ml, trial 3: 21.0 ml, trial 4: …
Group B's data is more precise.
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luther accidentally spilled his chemicals, and they splashed onto his a…
A. safety shower
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7. which of the following lab safety rules is not true? be sure to disp…
A. Be sure to dispose of all chemicals down the sink drain, rather than the trashcan.
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objective: to make a compound from a mixture. materials: iron, sulfur, …
A mixture is a combination of two or more substances that retain their individual properties and are not chemically combined. The iron - sulfur mixture is a heterogeneous mixture.…
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exnc. 71–72: solve part (a) and use the answers to parts (b) and (c) 71…
\( |w - 148| \leq 2 \) ### Problem 74:
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cookware companies have been using a chemical called c-8, which helps t…
B. cookware manufacturers who make pans out of steel only
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read the passage. there are several questions about this passage. stink…
3. Paragraph 4 explains that the sulfur on Io comes from volcanoes, and paragraphs 5 - 8 explain why Io has so many volcanoes.
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evaluating scientific explanations pre-test complete 1 2 3 4 5 which is…
B. by replicating experiments
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read the passage. there are several questions about this passage. stink…
4. Large quantities of sulfur make Io the smelliest place in the Solar System. ### Part B
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read the passage. there are several questions about this passage. stink…
3. the contrast between the smell of Io and other smelly places in the Solar System
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the idea of invisible ink had been around for a long time. write using …
British agents used invisible ink to send secret messages.
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2. using the graduated cylinder to the right, select the most accurate …
22.0 mL
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59 |3x - 9| > 0 60 |5x + 2| ≥ 0 63 \\left|\\frac{2 - 3x}{5}\ ight| = 2 …
\(x=-2\) or \(x = - 8\) #### Part (b): Solve \(|x + 5|\lt3\)
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the most common ways to treat cancer include ______. a. chemotherapy, r…
A. chemotherapy, radiation, and surgery
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dense than liquid water. when water molecules reach the freezing point …
San Francisco, being near the ocean (with large water bodies), has a more stable year - round temperature (less extreme) because water's high heat capacity moderates temperature (…
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number 4. draw a circle around the box with a line across the ci dissol…
less ### For the question "If frozen water were more dense than liquid water, what would happen to the water on Earth if that were the case?"
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give one possibility for the mystery reactant r in this organic reactio…
One possible reactant \( R \) is 2 - methyl - 2 - butene, whose skeletal structure is: ``` CH3 | CH3 - C = CH - CH3 ``` (In skeletal line structure, this is represented as: ``` C …
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1. select the \atom\ simulation, and build an atom with the following c…
- **Núcleo**: Dibuja un área central con 3 "P" (protones) y 4 "N" (neutrones) agrupados. - **Electrones**: Dibuja 3 "E" en órbitas (ej. círculos/elipses) alrededor del núcleo, mos…
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states of matter crossword across 3. change of a gas to a liquid 6. thi…
To solve the "States of Matter Crossword", we analyze each clue: ### Across Clues: 3. **Change of a gas to a liquid** → *Condensation* (process of gas → liquid). 6. **This type of…
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6. five ml of ethanol has a mass of 3.9 g, and 5.0 ml of benzene has a …
Benzene is denser.
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which dissolves more substances, sulfuric acid or water? sulfuric acid …
water (the checkbox next to "water" should be selected)
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what charge does the oxygen end of a water molecule have? slightly nega…
slightly negative
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d) healthcare providers giving accurate information 13. when analyzing …
d) All of the above ### Question 14
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part e how would you conduct your investigation? in your answer, explai…
To conduct the investigation (using a plant growth experiment as an example): 1. **Independent Variable (IV)**: The type of fertilizer (e.g., organic, synthetic, or no fertilizer …
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the image shows a molecular model of a compound using balls and sticks.…
B. The balls must be the same color.
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what is one of the four unique properties of water? a) high heat capaci…
A. High heat capacity
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what kind of bond holds together a water (h2o) molecule? o a) polar cov…
A) Polar covalent bond
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what is adhesion? a) when water molecules stick to other things. b) whe…
A) When water molecules stick to other things.
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what is a hydrogen bond? a) the bond that forms a water molecule. b) wh…
B) When a positive hydrogen atom bonds with a negative atom of another molecule.
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what is a hydrogen bond? a) the bond that forms a water molecule. b) wh…
B) When a positive hydrogen atom bonds with a negative atom of another molecule.
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select the three adjectives. dont select any articles (a, an, or the). …
heavy, bright, clean
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mark each change below p if it is physical and c if it is chemical. __c…
C ### 16. ice melting
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section: what is chemistry? complete each statement below by underlinin…
1. A chemical is any substance that has $\underline{\text{definite}}$ composition. Changes in chemicals, or chemical reactions, take place $\underline{\text{all around us}}$. ### …
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4) use the mass spectrum below to fill out the information in the table…
For the isotope with mass 88 amu (most abundant): - Protons: 38 - Neutrons: 50 - Mass: 88 amu - Relative Abundance: 82.58% (Adjust for other isotopes using the same logic.)
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in the chemical closet, you found an unlabeled vial with a solid piece …
The average atomic mass of element Z is approximately $\boldsymbol{85.47\ \text{amu}}$. (This matches the atomic mass of Rubidium (Rb), so the mystery element Z is likely Rubidium…
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2) determine the most likely element for the mass spectrum given below.…
Tungsten (justification: Its isotopic mass - intensity pattern in the mass spectrum matches the given peaks, with appropriate abundance and mass values relative to other options l…
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2) determine the most likely element for the mass spectrum given below.…
Zirconium (assuming the base peak in the mass spectrum corresponds to its atomic mass - related isotope abundance, with the most intense peak matching Zirconium's isotopic mass di…
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1) the mass spectrum of a sample of a pure element is given below. calc…
The average atomic mass is approximately \( 24.32 \) amu, and the element is Magnesium (Mg).
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1) the mass spectrum of a sample of a pure element is given below. calc…
The average atomic mass is approximately 63.55, and the element is Copper (Cu).
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86. explain when powdered iron is left exposed to the air, it rusts. ex…
Rusting is a reaction where iron (\(Fe\)) reacts with oxygen (\(O_2\)) and water (\(H_2O\)) from air (\(4Fe + 3O_2+ 6H_2O ightarrow 4Fe(OH)_3\), then to rust). By the law of conse…
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4) given 10.00 gram samples of licl, libr, lif and lii, place the sampl…
Order (least to greatest number of Li atoms): \( \text{LiI} < \text{LiBr} < \text{LiCl} < \text{LiF} \)
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*85. interpret graphs the mass of the elements iron and oxygen in four …
Yes, all four samples are the same compound. This is because the mass ratio of iron to oxygen is constant for each sample (e.g., for the first sample with 2 g oxygen and 5 g iron,…
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84. explain explain why this statement is false. \because there is no c…
The statement is false because physical changes (no compositional change) can still alter a substance’s appearance. Physical changes affect physical properties (state, shape, size…
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83. apply concepts a change in odor can also be a clue that a chemical …
One situation: When milk spoils. Fresh milk has a mild smell, but as it undergoes chemical changes (due to bacterial action), it develops a sour, unpleasant odor. Another situatio…
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82. sequence assume that water, mercury, and gallium are all at 40°c. a…
Gallium will freeze first (because its freezing point \(29.76^\circ\text{C}\) is the highest among the three, so as temperature drops from \(40^\circ\text{C}\), it will reach its …
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think critically *81. apply concepts devise a way to separate sand from…
1. First, use filtration to remove charcoal from the mixture (charcoal, sand, sugar, water). The charcoal is trapped on the filter paper, and the filtrate contains sand, sugar, an…
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80. the wax seems to disappear as a candle burns. how can the law of co…
When a candle burns, wax (a hydrocarbon) reacts with oxygen (\(O_2\)) from the air. By the law of conservation of mass, the total mass of reactants (wax + \(O_2\)) equals the tota…
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79. explain why the production of a gas does not always mean that a che…
The production of a gas does not always indicate a chemical reaction because gas can be produced through physical changes (e.g., boiling water to form water vapor, or releasing a …
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78. classify each of the following as a chemical change or a physical c…
** Chemical change ### Part (b) Digestion breaks down food (e.g., carbohydrates to glucose) via chemical reactions (enzymes, metabolism). New substances form.
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click to fix any capitalization errors below. click \submit answer\ if …
Submit Answer
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77. in photograph a, a coil of zinc metal is in a solution of sulfuric …
In photograph A, the formation of gas bubbles (around the zinc coil in sulfuric acid) indicates a chemical change (gas production is a sign of a reaction, e.g., $\ce{Zn + H_2SO_4 …
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75. identify each of the following as an element, compound or mixture. …
s: a. Element b. Compound c. Mixture d. Element e. Mixture f. Compound
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in the h mart food court, i find myself again, searching for the first …
H Mart is a "beautiful, holy place" for Zauner as it connects her to her Korean heritage and the memories of her mother and aunt. The Korean - themed scenes (mother - son interact…
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74. how are the items in each of the following pairs similar? how are t…
### Part a: Copper and Silver #### Similarities: - Both copper (Cu) and silver (Ag) are **metals** belonging to the transition metals group in the periodic table. - They exhibit c…
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73. classify the following properties of the element silicon as chemica…
Physical property ### Part (b) #### Step 1: Analyze the property type Brittleness (a measure of how easily a substance breaks) is a physical property. It is determined by the phys…
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72. identify each of the following items as a mixture or compound. clas…
To solve this, we recall the definitions: - **Compound**: Pure substance with fixed composition (atoms chemically bonded). - **Mixture**: Combination of substances (not chemically…
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71. you are standing in a kitchen and then in the middle of a park. whe…
In both the kitchen and the park, you see mostly mixtures.
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*70. use the arrangement of particles in solids and gases to explain wh…
In solids, particles are closely packed with very small interparticle spaces. In gases, particles are far apart with large interparticle spaces. Compression requires reducing inte…
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69. the state of a substance can change when the substance is heated or…
- **Solid**: Molecules are closely packed in a fixed, ordered structure, giving a definite shape and volume. - **Liquid**: Molecules are close but move past each other, having a d…
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68. is malleability an extensive property or an intensive property? exp…
Malleability is an intensive property. This is because intensive properties do not depend on the amount of the substance present, and malleability (the ability to be hammered into…
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the stimuli for kinesthesis is the ______ energy of joint and muscle mo…
C. mechanical
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*67. explain why mass cannot be used as a property to identify a sample…
Mass is an extensive property (depends on the amount of matter). Different quantities of the same substance have different masses, and different substances can have the same mass.…
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understand concepts use the data table to answer questions 63–66. | sub…
Ethanol ### Question 64
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photoelectron spectroscopy the complete photoelectron spectra of two un…
B. Element Y has a larger atomic radius than element X.
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*62. when ammonium nitrate (nh₄no₃) explodes, the products are nitrogen…
18 grams
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61. which type of property cannot be observed without changing the comp…
Chemical property
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59. use the word equation below to explain how a chemical change differ…
In the word equation \( \text{iron} + \text{sulfur} \xrightarrow{\text{heat}} \text{iron sulfide} \), a **chemical change** occurs because new substance (iron sulfide) forms from …
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below are the pes spectra for the valence electrons for oxygen and nitr…
### Part (a): Electron Configuration #### Step 1: Recall Atomic Numbers Oxygen (O) has atomic number 8; Nitrogen (N) has atomic number 7. #### Step 2: Write Electron Configuration…
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58. look up the word periodic in the dictionary. propose a reason for t…
The word "periodic" means occurring with regular intervals or a repeated pattern. The periodic table is named this way because the chemical elements are arranged such that their c…
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r1 – redox half reactions 1. write the redox half reaction for the foll…
Half - reaction: \( \text{Na} ightarrow \text{Na}^+ + e^- \); Original substance (Na) is oxidized. ### Problem 1b: Formation of chloride ion
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______ contain(s) detailed information about hazardous materials to hel…
c. Safety data sheets (SDS)
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all of the following statements regarding safety data sheets (sds) are …
b. If you are using more than one product, consult the SDS of only one of the products.
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56. not all element names come from english or latin words. the symbol …
Element symbols can be derived from the element's name in non - English/Latin languages. For example, W (tungsten) comes from German “wolfram” and Hg (mercury) from Greek “hydragy…
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measurement a. 726,444.0 b. 44585 c. 123.64 d. 0.0200 e. 0.09000333 f. …
Scientific Notation: \(7.26444\times10^{5}\) Number of Significant Figures: 7 ### Part b: 44585
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55. name the elements found in each of the following compounds. a. ammo…
Ammonia ($\ce{NH_3}$) contains nitrogen (N) and hydrogen (H). ### Part b: Potassium oxide ($\ce{K_2O}$)
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which element is represented by the pes absorption spectra shown?
Oxygen (O)
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54. describe the relationship between the three items in each of the fo…
- Hydrogen: Element - Oxygen: Element - Water: Compound Relationship: Hydrogen and oxygen react chemically to form the compound water. #### Part b