化学
化学反应、化学计量、分子结构与元素性质。
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lesson 3 fill in the missing vocabulary word for each definition. - ___…
ion ### Second Definition (anything that has mass and takes up space)
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a metal has a density of 8.35 g/ml. a student calculated the volume of …
The kg to g conversion factor is upside down
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ec4 review/hw name: binary ionic compounds with transition metals trans…
### Part 1: Binary Ionic Compounds with Transition Metals (Listing Ions with Roman Numerals) Common transition metals with variable charges (from oxidation charts) include: - $\bo…
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aluminum metal has a density of 2.70 g/ml. what is the volume, in milli…
1.040 mL (the option with "1.040 mL")
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what is a mathematical process used to convert values from one unit to …
C. Dimensional analysis
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a 25.5 g sample of metal has a density of 9.80 g/ml. what is the volume…
2.60 mL
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lesson 2 give 3 examples of properties of water that are caused by its …
### Lesson 2 - Fill in the missing vocabulary word for each definition: 1. **Definition: a bond resulting from two atoms sharing electrons** - This is a covalent bond. Covalent bo…
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a 2.54 g sample of sodium bromide is added to 32.4 g of water. what is …
34.9 g
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which of the following explains the correct number of significant figur…
2.8 cm³, the answer is limited by the total significant figures of the limiting term
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this graduated cylinder is marked with 1 ml increments. what is the vol…
25 mL
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properties of water what makes water so special? why? when you hear tha…
Two (from the formula \(H_2O\), the subscript 2 for H means there are 2 hydrogen atoms in a water molecule) ### Question 2
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match each description to its correct type of bond. labels: one polar m…
### Hydrogen bonds (1/4) - One polar molecule is attracted to another polar molecule. ### Polar covalent bonds (2/4) - An atom with high electronegativity shares electrons with an…
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select the statement that correctly describes one of the bulk elements …
Carbon (C) has four valence electrons and is likely to form covalent bonds.
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the diagram shows the logarithm of the first 13 ionisation energies of …
B. The element is aluminium.
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which change is chemical? (1 point) ○ water undergoing electrolysis: li…
A. water undergoing electrolysis: liquid water becoming oxygen and hydrogen molecules
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18. what elements make up the pain reliever acetaminophen, chemical for…
Elements in acetaminophen (\(C_8H_9O_2N\)): Carbon (C), Hydrogen (H), Oxygen (O), Nitrogen (N). Element with greatest proportion by number of atoms: Hydrogen (H) (9 atoms, more th…
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17. classify each of these samples of matter as an element, a c or a mi…
a. Mixture b. Mixture (or sometimes considered a solid solution, but generally a mixture) c. Compound d. Mixture e. Mixture f. Element (Note: For part b, glass is a heterogeneous …
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visual reading tool: buffers the figure below shows what happens to the…
Base ### Question 2
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match each vocabulary word with its meaning. 3. ______ element with 4 v…
d. carbon ### Question 4
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review vocabulary choose the letter of the best answer. 1. which is not…
C. boson ### Question 2
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09 question (2 points) you are trying to determine the identity of an u…
### Part 1 # Explanation: ## Step1: Analyze volume subtraction The volume difference is \(23.5\space mL - 14.7\space mL = 8.8\space mL\) (two significant figures in the decimal pa…
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when liquid gold becomes a solid, its particles get closer together. wh…
the rearrangement of particles in a physical change
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if there is 8 g of a substance before a physical change, how much will …
C. 8 g
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liquid plastic is frozen in a physical change that increases its volume…
C. Its mass will remain the same.
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what happens when a substance undergoes a physical change? ○ some physi…
A. Some physical properties change, but the substance keeps its identity.
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which can occur in a physical change? the mass can increase. the partic…
The particles can arrange in different ways.
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eugene describes the physical property of a material as \sweet and flor…
D. odor
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which scenario is an example of a physical change? wood is burned in a …
C. Lead is melted into a liquid to form pellets.
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which statement about the physical change of liquid water boiling into …
The heat added represents an energy change.
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what is an example of a physical change? ○ having less ash than the pap…
B. ice forming and then melting back into water
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read the excerpt from \do not go gentle into that good night.\ do not g…
aba aba.
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identify the properties of hydrophilic molecules. 1 they are non - pola…
3. They are polar and can dissolve in water.
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which is most likely to be true of a hydrophobic molecule? 1 it will be…
2. It will have no charge.
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at the molecular level, what gives water its high surface tension? 1 at…
3. At the surface, water is only surrounded on some sides by other water molecules, so more bonding occurs between molecules along and just below the surface, creating a "skin" of…
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the type of bond found between atoms within a water molecule is. answer…
Covalent bond
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in water, what causes the formation of hydrogen bonds? 1 attraction bet…
3. Attraction between the partially negative oxygen of one water molecule and the partially positive hydrogen of a different water molecule.
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state which element of water exerts a stronger pull on electrons. answe…
Oxygen
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ralph waldo emerson sociedad y soledad the necessity of solitude is dee…
B. Las discusiones grupales pueden ser energizantes si tratan temas positivos.
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which statement explains why sugar dissolves easily in water, but sand …
D. Sugar has a greater solubility than sand.
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question 51 which of the following isotopes has the longest half-life? …
D. Cobalt - 60
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which physical property can be measured? ○ color ○ density ○ odor ○ sha…
B. density
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bnoer chemistry name: chemistry matter review practice 1. match each di…
### Part 1: Matching Diagrams #### 1. Pure Element (only one type of atom) - Diagram C has only one type of atom (all circles are the same). So 1 - C. #### 2. Mixture of two eleme…
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question 47 the isotope most likely to be used to study the thyroid gla…
A. iodine - 131. ### Question 48
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pet imaging follows the emission of a positrons. b electrons. c neutron…
A. positrons. ### Question 44 (Table Sugar Reaction)
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which of the following molecules does not have a polar region? a water …
B. Triglyceride ### Second Question (pH scale measurement)
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question 31 a complete atom is electrically neutral because a the numbe…
C. the number of electrons equals the number of protons. ### Question 32
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3. draw valid lewis structures, and determine the molecular geometries …
To solve the problem of drawing Lewis structures and determining molecular geometries, we'll take $\ce{SiH4}$ as an example (the process is similar for other molecules/ions): ### …
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question 27 the difference in hydrogen ion concentration between soluti…
C. tenfold. ### Question 28
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structure of the atom review vocabulary element new vocabulary atom nuc…
- **element**: A pure substance with one type of atom, not breakable chemically. - **atom**: Basic unit of an element, with nucleus and orbiting electrons. - **nucleus**: Dense ce…
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the atomic number of an atom equals the number of ______ and the atomic…
D. protons; number of protons plus neutrons ### Question 18 (Atomic Weight Calculation)
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test content page 7 of 22 question 6 the following is a correct structu…
A. True
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the atomic number of an atom equals the number of _____ and the atomic …
D. protons; number of protons plus neutrons ### Question 18 (Atomic Weight Calculation)
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early chemists focused on answering questions. what is matter made of a…
Early chemists focused on answering questions about what matter is made of and how it changes.
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in an ionic bond a each atom gains electrons. b atoms share a pair or m…
C. oppositely charged atoms attract. ### Question 14 (Electrolytes):
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a substance that releases hydrogen ions in water is a base. a true b fa…
B. False ### Second Question (An atom that has gained or lost electrons is called an ion)
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chemically inert atoms always have their outermost electron shell full.…
A. True ### Question 8 (Chemistry is the study...):
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a base is an electrolyte that releases ions that combine with hydrogen …
A. True ### Second Question (About Complex Carbohydrate)
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determining electrons, neutrons, and protons 4. the 3 particles in an a…
a. Protons b. Neutrons c. Electrons ### Question 5:
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which of the following could be classified as matter? check all of the …
- desk - water - cloud - helium
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2. draw the shapes of the three 2p orbitals in 3-d (these are shown in …
The three 2p orbitals (2pₓ, 2pᵧ, 2p_z) have dumbbell - shaped electron density distributions, each oriented along one of the three mutually perpendicular axes (x, y, z). The 2pₓ o…
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sodium and chloride atoms combine readily because they both lose electr…
B. False ### Second Question (DNA and RNA are nucleic acids)
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test content question 1 0.3 points an atom with 10 protons and which ha…
B. False ### Question 2
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read this sentence from the passage. morgan, realizing that he had inve…
C. a fluid chemical mixture
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5. determine the number of significant figures in the following numbers…
a) The number of significant figures in \( 1.5060\times10^{-7}\) cm is 5. b) The number of significant figures in \( 0.00400630\) L is 6.
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3. convert 0.6590 kg/l into g/el using dimensional analysis. show compl…
\(6.590\times 10^{20}\space \text{g/EL}\)
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what is a product? something that goes into a chemical equation somethi…
something that comes out of a chemical equation
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chemistry worksheet - scientific notation, significant figures, units &…
### Question 1: Write in proper scientific notation #### Part A: 450,000 # Explanation: ## Step1: Identify the coefficient (1-10) Move the decimal to get \( 4.5 \) (from \( 450000…
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what were early chemists motivated by?
Early chemists (especially alchemists) were motivated by goals such as transforming base metals into gold (seeking the philosopher’s stone), creating an elixir of life for immorta…
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early chemists focused on answering questions.
Early chemists focused on answering **"What is matter made of?" and "How does matter change?"** (or similar fundamental chemistry - related) questions.
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early chemists focused on answering questions.
what (or descriptive, but "what" is a common fill - in here as early chemistry was about identifying and describing matter's composition, properties, etc.)
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what is a reactant? something that comes out of a chemical equation som…
The correct option is the one with "something that goes into a chemical equation" (the blue - colored option).
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what new combined branch of study was developed from the study of matte…
Biochemistry
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cheryl wants to perform an investigation that requires using hazardous …
1. Put on gloves, goggles, and an apron. 2. Design the investigation. 3. Perform the investigation. 4. Dispose of waste materials.
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the study of which type of material led most directly to the developmen…
d. batteries
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london dispersion forces are present in all molecules, but they are dom…
non - polar
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in this activity, you applied your understanding of the scientific meth…
D. what type of salt forms the largest crystals. (Note: Assuming the correct answer is about a measurable, objective property like size which is suitable for scientific method app…
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ph measures the acidity of a substance, and is described by the equatio…
3
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animal milk is a natural source of the disaccharide lactose. the monosa…
To solve this, we analyze each row: ### Row 1: "has 12 carbon and 11 oxygen atoms" - Lactose formula: $\ce{C_{12}H_{22}O_{11}}$? Wait, no—wait, the image shows lactose as $\ce{C_{…
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from nature: addresses, and lectures 1 the first in time and the first …
4. Man desires to find the interrelation of elements in nature.
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atomic theory: true or false the atoms of any one type of element (like…
To solve the problem of identifying the element by counting protons (atomic number) and using the Periodic Table, follow these steps: ### Step 1: Count Protons in Each Atom - **At…
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chemistry in context 2008-9 perhaps someone has tried to trick you with…
The density of tin is approximately \( 7.31\ g/cm^3 \) ### Problem 2
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b. the student’s claim is incorrect, because triclopyr application is a…
C. Digging up individual Scotch broom plants can cause soil disturbance.
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periodic trends: straw lab aluminum | al | 13 | 0.143 | 3.84 cm silicon…
As the atomic number increases going down a group on the periodic table, the atomic radius of the atom generally increases. ### For Question 2 (using Answer - Explanation Format):
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which of these is the primary drawback of digging up individual plants …
D. It could leave behind seeds that might germinate again and regrow in a new infestation
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this is a loose mixture of rock fragments and organic material that can…
soil
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c) no equipment d) helmet 2. where should broken glass be disposed of? …
c) Designated glass container ### Question 3
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part a: multiple choice 1. what should you always wear when handling la…
b) Safety goggles ### 2.
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select the two correct answers □ cutting a paper up □ wood burning □ cr…
B. Wood burning D. A browning apple (Note: Alternatively, Wood burning and Soured milk is also correct. The key is selecting two chemical changes. The options with new substances …
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1. students were given a chart containing different chemical symbols an…
- \( \text{O} \) - \( \text{N} \) - \( \text{Na} \)
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worksheet 2: safety handling of laboratory apparatus name: ____________…
b) Safety goggles ### Question 2
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18 what kind of shapes are free - flowing and natural? these shapes can…
B. Organic Shapes (assuming the second option is labeled as B, with the option text "Organic Shapes")
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periodic trends: straw lab objective: to create a visual representation…
To calculate the "Calculated Straw Length (cm)" for each element, we need to determine the scale factor. Let's assume the scale factor is to convert nanometers (nm) to centimeters…
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periodic trends: straw lab aluminum al 13 0.143 silicon si 14 0.117 pho…
Since the problem involves understanding periodic trends (atomic radius, ionization energy) and performing calculations related to a lab activity on these concepts, the relevant s…
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worksheet 2: safety handling of laboratory apparatus name: ____________…
b) Safety goggles ### Question 2
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what is required to create an anion and a cation? ○ ionization energy ○…
A. ionization energy
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11. which statement of molecules of the gas is in accord with the kinet…
B. The gas particles are in constant, random motion. ### Question 13 (About kinetic theory of gases)
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what corresponds to the atomic number? ○ number of hits ○ number of pro…
B. number of protons
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9. if the temperature of 1 liter of an ideal gas is increased from 4 k …
C. Four times as great ### Question 10
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9. if the temperature of a gas is increased, which of the following des…
(Assuming the correct option is the one stating that the average kinetic energy increases with temperature, e.g., if option A is "Increase" then) A. Increase ### Question 10 (Kine…
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propane exists as a gas at standard pressure and temperature above -44°…
B. Interactions among molecules, with the exception of collisions, are negligible ### Question 2 (Pressure increase with moles)