Chemistry
Chemical reactions, stoichiometry, molecular structures, and element properties.
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3. what are some characteristics of alkali metals? select two correct a…
C. Alkali metals are highly reactive and good conductors of electricity, E. Alkali metals have a single electron in the outermost shell
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in chemistry, the concept of a mole is fundamental for quantifying the …
A. A mole is used to relate the amount of a substance to its mass, where the mass is determined based on the substance’s molecular or atomic weight.
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which words create the rhyme scheme in the second stanza? \wild call\ a…
"tide" and "denied"
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use the drop-down menus to answer the questions about john masefield’s …
three ### For the second question "What is the rhyme scheme of the first stanza?":
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clearly mark the letter of the best answer for questions 1 – 15 on the …
c) \(^{17}\text{O}^{2-}\) ### Question 2
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to improve the safety of your location and comply with regulations rega…
D. Download them from the chemical manufacturer’s websites.
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use the drop-down menus to answer the questions about jo masefields poe…
- How many stanzas are in the poem? 3 - What is the rhyme scheme of the first stanza? AABB - What poetic structure does Masefield use? Quatrains (with iambic tetrameter and repeat…
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section 2.2 mixtures 1. how might one separate a mixture of water and s…
One can separate a mixture of water and salt by evaporation (heating the mixture to vaporize the water, leaving salt behind) or distillation (collecting and condensing the water v…
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i. multiple choice: encircle the letter of the correct answer. 1. which…
C. Form ### Question 2
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physical state | definite shape? | definite volume? | readily compressi…
One can separate a mixture of water and salt by evaporation. Heat the salt - water solution; the water will evaporate as vapor, leaving the salt behind. (Distillation can also be …
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5. complete the following table. | physical state | definite shape? | d…
To complete the table, we recall the properties of the three physical states (solid, liquid, gas): ### For Gas: - **Definite shape?**: No (gases take the shape of their container)…
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practice problems in your notebook, solve the following problems. secti…
b. burning gasoline in an engine ### Question 2
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draw the lewis structure for the methane (ch₄) molecule.
The Lewis structure of \( \text{CH}_4 \) has a central carbon atom bonded to four hydrogen atoms via single covalent bonds. The structure is represented as: ``` H | H - C - H | H …
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elements in order of the trend. numbers based on trends. may also selec…
s (Key Points) - Valence electrons: Ca: $2$, F: $7$, Si: $4$, Ar: $8$ - Oxidation numbers: Rb: $+ 1$, Al: $+ 3$, Te: $- 2$, Sn: $+ 4$ - Elements by location: 1. Ta, 2. S, 3. Ti - …
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page 2 of 4 dp alum : kal(so₄)₂·12h₂o ap alum + 3h₂(g) = 6 - hydrogen 5…
### Reflection Question 1 Explanation: To determine the step responsible for low yield in alum synthesis, we analyze common synthesis steps (e.g., precipitation, filtration, cryst…
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it does not have a set meter. it is a poem with a fixed form. it does n…
The incorrect statement is: It is a poem with a fixed form.
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b) energy is always lost c) energy can only be changed from one form to…
C) Potential energy ### Question 5
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b) energy is always lost c) energy can only be changed from one form to…
C) Potential energy ### Question 5
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esta imagen es un ejemplo de un(a) compuesto mezcla molécula átomo
D. Átomo
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5. what is the atomic mass of an element with 3 isotopes with the follo…
s: 5. Atomic mass: \(\boldsymbol{42.65}\) amu 6. Atomic mass: \(\boldsymbol{\approx 32.09}\) amu 7. Element: \(\boldsymbol{\text{Chlorine (Cl)}}\)
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part 1: atom screen 1. which particle(s) are found in the center of the…
Protons and neutrons ### Question 2
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describe la relación de los átomos mostrados arriba. un cambio en el es…
A. Un cambio en el estado de la materia de líquido a gas es un cambio físico.
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14.5789 - 0.5009 = 14.0789 14.0789 g × \\frac{1\\,\\text{mol al}}{26.98…
\boxed{89.26} (or depending on significant figures, maybe 89.2 g or 89.3 g, but based on calculation, ~89.26)
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durante la clase de ciencias, mientras estudias mezclas, mezclas azúcar…
solubilidad; Agrega agua a la mezcla y disuelve el azúcar
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suponga que tiene un recipiente lleno de hierro y arena. puede separar …
A. utilizas un imán; mezcla
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3. what is the atomic mass of phosphorous if phosphorous-29 has a perce…
The atomic mass of phosphorous is approximately \( 29.86 \) amu (or rounded as needed, often close to 30 amu considering significant figures, but the calculated value is ~29.86). …
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¿qué imagen(es) se considerarían sustancias puras? image of five molecu…
B. II y IV (assuming the purple option is labeled B, as per the visual: purple is "II y IV", green "I y II", orange "III y V", teal "V")
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según la escala, ¿cuál de estas sustancias es el ácido más fuerte? opci…
jugo de limón
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directions: go to the phet simulation \build an atom\ to answer the fol…
protons, neutrons ### Question 2
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sort the data collected about the element copper into qualitative or qu…
### Qualitative Data - red - orange color - easy to stretch into wire - solid at room temperature ### Quantitative Data - density of \(8.96\space g/cm^{-3}\) - melting point of \(…
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worksheet #2 – isotopes & average atomic mass answer the following ques…
An isotope is a variant of an element with the same atomic number (same number of protons) but a different number of neutrons (different mass number). ### Question 2
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el gráfico muestra que la tasa de reacción y la temperatura están _____…
C. directamente, aumenta (assuming the orange option is labeled C; if the labeling is different, adjust the identifier but keep the text "directamente, aumenta")
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unit 1 harnessing human energy: review fill in the blank: fill in the b…
### Fill in the Blank Answers: 1. The energy stored in an object is called \(\boldsymbol{\text{potential}}\). 2. The energy of a moving object is called \(\boldsymbol{\text{kineti…
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which observation is the most objective? - the crystals in this image r…
The crystals in this image are jagged and white and developed on the green string between the two solution - filled glass jars
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read the poem. skimming the bottom in the company of toes, i observe th…
The poem's rhyme scheme is \( \boldsymbol{ABCBDEFE} \) (or a more simplified view where lines 2 & 4 rhyme (B - B) and lines 6 & 8 rhyme (E - E), with the other lines having unique…
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the passage below describes an experiment. after a severe winter storm,…
a control group
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what is the purpose of an msds? ○ to prevent service technicians from l…
C. To document how to safely handle and dispose of hazardous materials
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element name: boron, na, gallium, blank, tc, lead atomic symbol w/ isot…
To solve the missing parts of the table, we use the relationships between atomic number, protons, neutrons, electrons, mass number, and charge: ### 1. For the row with atomic numb…
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worksheet #1 - protons, neutrons, and electrons practice worksheet fill…
To solve the worksheet, we use the following concepts: - **Atomic Number (Z)**: Number of protons (and electrons in neutral atoms). - **Mass Number (A)**: Sum of protons and neutr…
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11) match the illustrations with the states of matter.
To solve this, we analyze the particle arrangements for each state of matter: ### Step 1: Analyze the first illustration (above the cup) The particles are far apart, moving freely…
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the particles in the solid shown here are ______. distributed crystalli…
B. crystalline (assuming the options are labeled as A. distributed, B. crystalline, C. amorphous, D. luminous)
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which of the following chemicals, found in tobacco smoke, is als a. amm…
D. arsenic
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the particles in the solid shown here are ______. distributed crystalli…
B. crystalline
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snc2p chemistry 3. classify each of the materials below. in the center …
To solve this, we analyze each material based on the definitions: - **Pure Substance**: Made of one type of particle (element or compound). - **Mixture**: Made of two or more subs…
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what is the difference between an amorphous solid and a crystalline sol…
The correct option is the third one: "Amorphous solids have particles that are randomly arranged while crystalline solids have particles in" (assuming the full option would state …
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honey has a higher level of ______ than water, so it has a higher resis…
A. viscosity
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____ is the only substance to naturally exist in all three forms of mat…
C. Water
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5) match the descriptions with the states of matter. matter has a defin…
1. Matter has a defined shape and volume that will not change: Solid 2. Matter does not have a defined shape but still retains a defined volume and has viscosity: Liquid 3. Matter…
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part c in a separate location, take notes from the sources you’ve ident…
To complete the note - taking for the presentation, we analyze each topic using the provided sources: ### Topic: Chemical reactions of fossil fuels - **Source**: Combustion of Fue…
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the compound rule the physical and chemical properties of a blank have …
- First blank (after "a"): compound - Second blank (after "have"): nothing - Third blank (lower left): elements - Fourth blank (lower right): properties
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chemistry matter review practice name: blank 1. match each diagram with…
### Part 1: Matching Diagrams (Explanations for each match) 1. **Pure Element (only one type of atom)**: Diagram C has only one type of atom (all circles are the same), so match w…
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19) identify the properties listed below as properties of metals (m), o…
m #### b)
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match the following h₂ mgcl₂ bi hg n₂ i₂ c₆h₁₂o₆ b f₂ nacl h₂so₄
\( H_2 \) matches with the description of "Diatomic gaseous element (hydrogen gas)" (or equivalent based on full right - hand text). (Note: For the full set, each substance must b…
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• what is acid rain? which fossil fuel causes acid rain? what are the c…
- Acid rain: Precipitation (rain, snow, etc.) with pH < 5.6, containing sulfuric/nitric acids from air pollutants. - Fossil fuel: Coal (primarily, due to high sulfur), also oil/na…
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4) put a checkmark next to the description if its a chemical property o…
To solve this, we recall: - **Physical properties** can be observed/measured without changing the substance’s chemical identity (e.g., volume, color, mass). - **Chemical propertie…
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4) put a checkmark next to the description if its a chemical property o…
To solve this, we recall: - **Physical properties** are observed without changing the substance’s chemical identity (e.g., volume, color, mass). - **Chemical properties** relate t…
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match the following made of particles made of atoms made of molecules w…
To solve this matching problem, we analyze each term based on chemical concepts: ### 1. *Made of Particles* All matter (elements, compounds, mixtures) is made of particles (atoms,…
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a characteristic of matter is a(n) ______. ○ property ○ ability ○ mark …
A. property
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____ is anything known to have mass and that takes up space. a solid an…
C. Matter
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based on the electron configuration shown in the image, where on the pe…
Period 4 - The victim was not attacked by a cougar
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chemical reactions of fossil fuels - what kind of chemical reaction occ…
s: 1. The chemical reaction is combustion (oxidation - reduction). Products (besides energy) include $\ce{CO2}$, $\ce{H2O}$, and may include $\ce{CO}$, $\ce{SO2}$, $\ce{NO_x}$, so…
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the first stage in designing your presentation is to make a list of que…
Natural Science - Chemistry
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the first stage in designing your presentation is to make a list of que…
Since no specific question is provided (e.g., answering one of the listed questions, analyzing the research approach, etc.), it's not clear what the task is. If you want to answer…
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example 9 determine the molar mass of mg(no₃)₂.
The molar mass of \(Mg(NO_3)_2\) is approximately \(148.32\) g/mol (or \(148.3\) g/mol depending on rounding).
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carbon-14 has a half-life of 5,730 years. how long will it take for 112…
17,190 years
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complete the chart. get help here. columns: frying an isolated eggplant…
To solve this, we analyze each process: ### 1. Frying an Isolated Chicken - **Chemical makeup changes**: Yes (cooking involves reactions like Maillard, so chemical bonds change). …
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a meteorite contains 0.17 g of nickel-59, a radioisotope that decays to…
5
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which of the following would help jamal to reason effectively? jamal is…
B. asking questions based on scientific knowledge (assuming the options are labeled with letters, if not, the option text is "asking questions based on scientific knowledge")
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short answer 1. how did the burning of modern materials like plastics a…
Burning plastics and electronics releases toxic chemicals (e.g., heavy metals, dioxins) into the dust. Ordinary fire debris has fewer such toxins, making 9/11 dust more dangerous …
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a small amount of americium-241 is used in smoke detectors. a stream of…
A. long half - life
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an article about half-lives describes a parent isotope. what is a paren…
D. an isotope that undergoes radioactive decay to form a more stable isotope
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isotope notation puzzle protons\tneutrons\telectrons\tatomic number\tma…
To solve the Isotope Notation Puzzle, we use the following relationships: - **Atomic Number (Z)** = Number of Protons (always). - **Mass Number (A)** = Protons + Neutrons. - **Net…
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1 which compound released from burning plastics is especially dangerous…
c) Dioxins ### Matching Questions 1. **Combustion**
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niobium-91 has a half-life of 680 years. after 2,040 years, how much ni…
18.75 g
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samarium-146 has a half-life of 103.5 million years. after 1.035 billio…
0.200 g
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what is a non-polar molecule? a. a molecule with a positive charge b. a…
d. A molecule with an even distribution of electrons
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which molecule is an example of a non-polar molecule? a. ammonia (nh₃) …
d. Methane ($\ce{CH_4}$)
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part b in a chemical reaction, substances react in a specific ratio. ch…
It is important for a company carrying out a chemical reaction to know the ratio of substances because: 1. **Efficiency**: It ensures the reaction proceeds completely, avoiding wa…
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what is a physical property of this yarn ball? the yarn ball is blue. t…
C. The yarn ball is pink. (Note: If the actual yarn ball in the image is of a different color among the options, the answer would change accordingly. But based on typical similar …
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which statement correctly compares chemical reactions with nuclear reac…
The correct statement is: "In chemical reactions, small amounts of energy can be absorbed or released. In nuclear reactions, changes in energy are much larger."
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the periodic table is arranged by various patterns. describe the patter…
Across a row (period) in the periodic table, the charge of ions formed by main - group elements shows a pattern. Metals on the left tend to lose electrons to form positive ions (c…
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which of the following molecules is symmetrical and non-polar despite h…
b. Carbon dioxide ($\ce{CO_2}$)
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section #1: history of the periodic table 1) who is attributed with the…
Dmitri Mendeleev ### Question 2
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question 2: analyze and extend part a explain whether changing the rati…
Changing the ratio of baking soda and vinegar does change the amount of carbon dioxide ($\ce{CO_{2}}$) produced. This is because the reaction $\boldsymbol{\ce{NaHCO_{3} + CH_{3}CO…
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an atom that has 84 protons and 86 neutrons undergoes a reaction. at th…
It emitted an alpha particle in a nuclear reaction.
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mixture: no mixture: yes atoms: 3 atoms: 8 elements: 2 elements: 3 mole…
To solve the problem of identifying compounds and mixtures, we analyze the left and right sections: ### Left Section (Mixture: NO) - **Atoms**: 3 (one zig - zag, two black). - **E…
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environmental and policy implications the chemical lessons of 9/11 push…
b) Fuel burns without enough oxygen, producing toxic byproducts ### Question 2
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molecules: compounds: mixture: image of three molecular structures (eac…
To solve the problem of identifying molecules, compounds, and mixtures (or other related counts like atoms, elements), we analyze the given diagram: ### Step 1: Identify Molecules…
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part d carry out the investigation you planned. record your data in the…
To complete this investigation, we can design a simple experiment by varying the amount of baking soda while keeping the amount of vinegar constant (or vice - versa) and observing…
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which of the following statements about secondhand smoke is not true? a…
C. Secondhand smoke is inhaled less deeply than firsthand smoke.
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group 2 elements have two valence electrons. which kind of bond will th…
D. An ionic bond is likely because they will want to give away two valence electrons in order to become stable.
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use the periodic table to answer the question. which statement correctl…
To solve this, we analyze the periodic table positions: - Francium (Fr) is in Group 1 (IA), so it has 1 valence electron. - Barium (Ba) is in Group 2 (IIA), so it has 2 valence el…
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on which atomic property proposed by henry moseley is the current perio…
A. atomic number
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atomic structure unit test what quality differentiates hydrogen (h) fro…
B. It is a non - metal
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3. calculate the theoretical yield in grams for this reaction. assume t…
The theoretical yield of alum is approximately \( \boldsymbol{8.79\,\text{g}} \) (depending on the exact molar masses used, but following the given values, this is the result).
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chem 1123 chapter 3: electromagnetic spectrum and periodic properties t…
The wavelength of the electron is approximately \(\boldsymbol{7.27\times10^{-11}\space m}\) (or \(72.7\space pm\)).
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part c list the amounts of baking soda and vinegar that you will use in…
Here is a sample list of combinations (holding baking soda constant at 1 tablespoon and varying vinegar): - Baking Soda: 1 tablespoon, Vinegar: 10 mL - Baking Soda: 1 tablespoon, …
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1. which of the following is the best example of a physical change? - b…
D. Melting of an ice cube
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part b now decide how many different combinations of baking soda and vi…
I will try 4 different combinations of baking soda and vinegar. (Note: Any number ≥3 is acceptable, e.g., 3, 4, 5, etc. The answer can be adjusted as per preference as long as it …
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case study excerpt: chemical analysis of wtc dust in the months after 9…
The dust had a high pH because it contained pulverized concrete and gypsum from drywall (these materials have alkaline - forming components). This highly alkaline dust could burn …