化學
化學反應、化學計量、分子結構與元素性質。
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the reaction of copper(ii)oxide breaking up to give copper element and …
2) Oxidation - reduction and Decomposition
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choose the case that is not a conjugate acid-base pair. 1) $\\ce{hco3^-…
4) $\ce{H3PO4}$, $\ce{PO4^{3-}}$
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question 10 (1 po listen how many mols are present in 0.02698 g of alum…
3) 1.000 millimol
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question 9 (1 point) listen for the aqueous reaction of sulfuric acid a…
1) $\ce{H_{2}SO_{4}(aq) + 2NaOH(aq) ightarrow Na_{2}SO_{4}(aq) + 2H_{2}O(l)}$
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4. the electron dot structure for methane, ch₄, can be classified using…
C. tetrahedral (assuming the options are labeled as A. Triangular, B. square, C. tetrahedral, D. Triangular pyramidal; if the original options have different labels, adjust accord…
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for the balanced equation, $2\\ce{nh_3(g)} + 3\\ce{cuo(s)} \ ightarrow …
4) 30.3 mols CuO
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3. what is the name of the following formula, $\\ce{h_{2}so_{4}(aq)}$? …
B. sulfuric acid
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question 7 (1 point) listen the correct formulas for manganese(ii)hydro…
3) \(Mn(OH)_2\) and \(Cu(NO_3)_2\)
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2. what is the correct name for the compound indicated by the formula, …
A. Iron (III) sulfide
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question 6 (1 point) listen atomic size and ionization energy both incr…
2) False
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question 5 (1 point) listen the balanced molecular equation for the rea…
4) $\ce{HNO3(aq) + KOH(aq) -> KNO3(aq) + H2O(l)}$
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1. what is the formula of calcium bromide? options: ○ cabr ○ cabr₂ ○ ca…
B. \(CaBr_2\)
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question 4 (1 point) listen in lewis dot structure, only the central at…
2) False
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question 3 (1 point) listen according to bronsted lowry theory an acid …
2) Proton donor, Proton acceptor
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how could you test for an endothermic reaction and tell that one has oc…
To test for an endothermic reaction, measure the temperature of the reaction system (e.g., with a thermometer). An endothermic reaction occurs if the temperature of the system (or…
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30. which of the following best describes the energy transformations th…
D. chemical → electrical → light ### Question 31
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question 2 (1 point) listen the correct names of the acids hcl and hbr …
1) Hydrochloric acid and Hydrobromic acid
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question 1 (1 point) listen c and s are 1) solid nonmetals 2) are diato…
1) Solid nonmetals
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24. what is the definition of convection? a. when heat transfers throug…
C. A hot liquid or air that expands, becomes less dense, and rises or becomes more dense, and sinks. ### Question 25
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what is a key characteristic of a homogeneous mixture? choose 1 answer:…
B. The components are evenly mixed, and the mixture looks the same throughout.
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what is a key characteristic of a homogeneous mixture? choose 1 answer:…
B. The components are evenly mixed, and the mixture looks the same throughout.
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which of the following best describes a homogeneous mixture? choose 1 a…
B. a physical combination of substances where the components are evenly distributed and appear uniform
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complete the following statements. - mixtures are a ▼ combination of tw…
- For the first blank in "Mixtures are a [blank] combination of two or more [blank] substances in any proportion": The first blank is "physical" and the second blank is "different…
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homogeneous mixtures are also called solutions. which of the following …
C. The components are evenly distributed, giving them a uniform appearance.
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s a 1 week streak! substance 1 substance 2 substance 3 complete the fol…
- Substance 1 is a(n) \(\boldsymbol{\text{compound}}\) (or "pure substance, compound"—correcting from "mixture"). - Substance 2 is a(n) \(\boldsymbol{\text{element}}\) (correcting…
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Question was provided via image upload.
Para representar el modelo de partículas: 1. **Agua pura**: Dibuja círculos (o símbolos) para $\ce{H2O}$ espaciados uniformemente, sin partículas de azúcar. 2. **Agua + poco de az…
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which statement about louise nevelson’s sculptures is true? ○ the objec…
D. A single color and repeated box shapes create unity.
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illustrating dilute and concentrated solutions the particle model of ma…
### 1. Agua pura: Dibuja círculos (o símbolos) representando partículas de $\ce{H_2O}$, dispersos uniformemente en el rectángulo, con distancia entre ellos (estructura líquida, si…
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in the 19th century, the hulls of wooden ships were often lined with mu…
C
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physical science: semester exam 1. what is the scientific method? a. a …
B. A process used by scientists to explore observations and answer questions. ### Question 2
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formula. - minerals are mostly ____________, meaning all parts of a min…
○nonrenewable
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ance needs to fulfil the following criteria to be dered a mineral. ust …
nonrenewable (the option "nonrenewable" should be selected, so the answer is the circle next to "nonrenewable" or simply stating "nonrenewable" as the correct choice for the resou…
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select the answer from the menu. the smallest particle of an element is…
A. atom
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physical science mid term 13 of 15 when a battery - operated train is t…
First box: chemical energy, Second box: electrical energy, Third box: mechanical energy
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the periodic table of the elements organizes elements according to thei…
Be, Ca, Sr (the three elements in Group 2: Be, Ca, and Sr from the checkboxes)
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chem semester 1 final 2024 which of the following is a chemical change?…
burning a piece of paper to ash
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select all the examples of a chemical change. □ ice melting □ nail rust…
The examples of chemical change are: - nail rusting - bread baking - wood burning - milk spoiling (Note: Ice melting is a physical change, so it's not selected.)
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select all of the terms that identify a part of an atom. □ proton □ iso…
A. proton, C. nucleus, D. electron
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select the answer from the menu. copper, silver, and nickel are all cla…
transition metals
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select the answer from the menu. when an atom gains an electron, the at…
have a negative charge
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select the answer from the menu. the element krypton is a gas that show…
in the same group
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select the answer from the menu. appearance, texture, and density are c…
physical properties
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select the answer from the menu. a doorbell circuit converts electrical…
sound energy
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select the answer from the menu. calcium carbonate (caco₃) is considere…
elements
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table 2 - calculations (you must show your calculations, as shown in th…
To calculate the mass of each unknown sample, we use the formula \( \boldsymbol{\text{Mass} = \text{Number of Moles} \times \text{Molar Mass}} \). Here are the calculations for a …
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using the appropriate prefixes. a) n₂o₅ b) cf₄ c) scl₃ d) so 4. which o…
b. \( \text{CF}_4 \)
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3. name each of the following molecules using the appropriate prefixes.…
a) Dinitrogen pentoxide b) Carbon tetrafluoride c) Sulfur trichloride d) Sulfur monoxide
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note: you may write your steps to calculation on separate piece of pape…
To solve for the mass of chemical substances for each unknown sample, we use the formula: $\text{Mass of Chemical Substances} = \text{Mass of Chemical with container} - \text{Mass…
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10 elements on the periodic table can be represented by chemical symbol…
B. Ne
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the number of carbon atoms present in 0.062 * mol of acetic acid, ch3co…
a. \(7.5\times 10^{22}\) atoms
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9 determine the identity of the following element: this element has 5 v…
D. arsenic
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8 brandon is trying to remember how the physical and chemical propertie…
C. I, IV and V only
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7 the periodic table includes all of the known elements in the world. h…
A. by their atomic number
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ionic naming 12. mercury (ii) oxide 13. calcium nitride 14. zinc bromid…
20. Copper(I) phosphide 21. Silver(I) sulfide (or Silver sulfide) 22. Tin(IV) nitride 28. Strontium sulfite 30. Sodium carbonate 33. Beryllium hypochlorite (And similarly, other p…
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the periodic table consists of elements following a repeating pattern o…
A. outermost electrons.
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5 which statement describes why elements are classified into the groups…
C. The elements in each group have similar properties.
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usually, elements within the same group have the same number of valence…
C. helium
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determine the molar mass of potassium hydroxide. 73.12 g/mol 95.21 g/mo…
56.11 g/mol ### Second Sub - Question (What is the unit for molar mass?)
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3 antimony is like a nonmetal in that it is a brittle, crystalline soli…
A. metalloids
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consider the combustion of propane: c₃h₈ + 5o₂ → 3co₂ + 4h₂o. if 2.5 mo…
12.5 moles (The option is "12.5 moles") ### Second Sub - Question (Moles of Water from Mass)
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2 directions: select each correct answer. more than one answer may be c…
They all have two electrons in their outermost shell., They all tend to become positive ions when they bond with other elements., They all have similar chemical and physical prope…
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how many atoms in total are there in 1.83 mol of aluminum oxide molecul…
d. $5.51 \times 10^{24}$ ### Second Question (Moles of $\ce{H2O}$ Produced)
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how many valence electrons does a neutral atom of oxygen have? a. 6 b. …
A. 6
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the skeleton equation representing the neutralization of aluminum hydro…
3 (the option with 3) ### Second Sub - Question (Moles and Mass of Neon)
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10 an atom of fluorine has the atomic number 9, and its mass number is …
A. W
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9 which of the following statements is true of the mass number of an at…
A. The mass number of an atom is equal to the sum of its number of protons and neutrons.
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7 elements on the periodic table are organized in order of their a. ele…
B. atomic numbers.
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3 which of the following elements would most likely have the physical p…
C. Ag
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question 1. determine the correct formulas for the compounds formed bet…
a. \( \text{Mg(OH)}_2 \) b. \( \text{K}_2\text{SO}_4 \) c. \( \text{NH}_4\text{Cl} \) d. \( \text{Li}_3\text{PO}_4 \)
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one mole of ammonia, nh3, is made up one atom of nitrogen and three ato…
True ### Second Question (Molecules in 0.500 moles of CH₄)
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which of the following statements about the molar mass of an element is…
The molar mass is the mass in grams of 6.022×10²³ atoms of the element. ### Second Question (Standard Unit for Chemical Quantity):
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ionic naming 1. rubidium and iodine 2. barium and chlorine 3. lithium a…
1. Rubidium iodide (RbI) 2. Barium chloride (BaCl₂) 3. Lithium selenide (Li₂Se) 4. Magnesium nitride (Mg₃N₂) 5. Cesium sulfide 6. Barium oxide 7. Aluminum iodide (AlI₃) 8. Mangane…
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what is the molar mass of magnesium sulfate, mgso₄? (use approximate at…
120.38 g/mol (corresponding to the first option: 120.38 g/mol) ### Second Sub - Question (Atom Ratio in Potassium Nitrate)
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what is the percent composition by mass of oxygen (o) in carbon dioxide…
72.73% ### Second Question: Largest Atomic Molar Mass
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fall final exam (2025 - m) what is a solute? image of pouring a substan…
A. is a substance that is dissolved in the solvent.
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fall final exam (2025 - m) what is a solvent? solvent definition a solv…
The correct option is: "a substance that dissolves another substance."
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fall final exam (2025 - m) what is a solution? a solution is made up of…
A. is a uniform mixture of 2 or more substances
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1. which reaction between halogens and halide salts will occur? a. $\\c…
A. \( \boldsymbol{F_2(g) + FeI_2(aq) ightarrow FeF_2(aq) + I_2(l)} \) ### Question 2
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what is water referred to? water universal solvent the elixir of life i…
B. is often called the universal solvent (assuming the options are labeled as A, B, C with A: the elixir of life, B: is often called the universal solvent, C: lawn maintenance req…
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mixed naming practice when given the name, give the formula, when given…
(Here are the answers for each sub - problem as per the above explanations. For example, for Chromic acid (Acid naming 1), formula is $H_2CrO_4$; Hydrobromic acid (Acid naming 2) …
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porcelain originated in china around 2,000 years ago, but its productio…
C. It identifies when and where porcelain eventually began to be produced in Europe.
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fall final exam (2025 - m) what is the density of pure water? 10.0 g/ml…
B. 1.00 g/mL
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fall final exam (2025 - m) possible points: 4.11 match the term to the …
- "Sticky force of molecule to form a surface" → surface tension - "When molecules of the same substance stick together" → cohesion - "When molecules of different substances stick…
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the recipe for aquarium saltwater is listed below. if the following wer…
- 2 gallons freshwater: Solvent - 2 grams salt: Solute
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order the nitrogenous compounds from most toxic (1) to least toxic (3).…
First box: Ammonia, Second box: Nitrite, Third box: Nitrate (Order from most toxic (1) to least toxic (3) is Ammonia (1), Nitrite (2), Nitrate (3))
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two substances are placed in a flask. substance a has a density of 4 g/…
Float
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question 3. drag and formula and name for each binary ionic compound fo…
a) Formula: $\text{CoCl}_3$; Name: Cobalt(III) chloride b) Formula: $\text{CaBr}_2$; Name: Calcium bromide
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question 2. a team of chemists is cataloging binary ionic compounds for…
- Lithium phosphide: \(Li_3P\) - Manganese(II) oxide: \(MnO\)
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water is considered a polar molecule. select the configuration of charg…
oxygen side (-), hydrogen side (+)
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match the term to its definition. a substance in which particles dissol…
- "a substance in which particles dissolve in" —— solvent - "water is often termed this because it dissolve most other substance" —— universal solvent - "the substance that dissol…
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how does the density of saltwater compare to freshwater? ○ saltwater is…
A. Saltwater is more dense than freshwater
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question 19 (3 points) matching terminology column a 1. 19. what is rhy…
1. 19: b. the ordered pattern of rhymes at the ends of the lines of a poem 2. [No correct match in given Column B for theme, but if we assume a mistake, maybe a different set, but…
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for each of the following, draw the lewis diagrams, predicted formula f…
B. \( Li_2O \) ### Question 4
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exit ticket for each of the following, draw the lewis diagrams, predict…
B. \( \text{Li}_2\text{O} \) ### Question 4
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a factory installs robotic arms that assemble products and improve prod…
B. Mechanical Engineer & Industrial Engineer
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a product must be redesigned so it is easier and safer for people to us…
Industrial Engineer & Biomedical Engineer
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a company is improving a delivery system so packages move smoothly thro…
Industrial Engineer & Mechanical Engineer
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12/18 final exam a city installs solar panels on public buildings and c…
Electrical Engineer & Environmental Engineer
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which type of engineer is most responsible for designing roads, bridges…
B. Civil Engineer
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q2 chemistry: u4l3.5 lattice structure intro teacher: date: 2. *explain…
The ionic bond between aluminum and chlorine forms because aluminum (a metal) tends to lose electrons and chlorine (a non - metal) tends to gain electrons to achieve stable electr…