化学
化学反应、化学计量、分子结构与元素性质。
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1 this video shows a traditional method of harvesting sea salt. how is …
B. They are both white solids, E. They are both made of tiny crystals
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bsc 1005 exam1 fall 2025 started: oct 16 at 8:35am quiz instructions qu…
bonding properties
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scavenger hunt -- types of chemical bonds -- location 1 research: find …
Linus Pauling was an American chemist. He contributed to chemical bonding by developing the concept of electronegativity and describing covalent bonds. He won Nobel Prizes for Che…
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fill in the name and empirical formula of each ionic compound that coul…
| cation | anion | empirical formula | name of compound | |---|---|---|---| | \(Cu^{+}\) | \(F^{-}\) | \(CuF\) | copper(I) fluoride | | \(Rb^{+}\) | \(N^{3 -}\) | \(Rb_{3}N\) | ru…
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a chemist prepares a solution of copper(ii) sulfate (cuso₄) by measurin…
\(0.29\space mol/L\)
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calculate the following % errors. show your numbers plugged into the eq…
1. $6.25\%$ 2. $7.5\%$ 3. $\approx0.43\%$ 4. $\approx33.33\%$ 5. No, because her percent error is approximately $0.79\%$ which is greater than $0.500\%$.
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match the following labels to the correct water molecule representation…
From left to right: Ice, Water, Gas.
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a student takes a sample of water with a salinity of 21 ‰ or psu and al…
\(9.44\)
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error and percent error by tiffany duda multiple - choice question perc…
B. False
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error and percent error by tiffany duda find the percent error for the …
0.56%
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match the following labels to the correct water molecule representation…
- The left - most structure (closely packed, orderly) is Ice. - The middle structure (less closely packed, some movement) is Water. - The right - most structure (molecules far apa…
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a student takes a sample of water with a salinity of 21 ‰ or psu and al…
\(9.44\)
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6. what can happen to rocks over time according to the video? a. they r…
6. b. They can turn into soil 7. b. The continuous transformation of rocks from one type to another 8. d. Sedimentary rocks 9. c. Igneous
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the large number of hydrogen bonds causing water molecules to stick to …
1. viscosity 2. specific heat 3. surface tension
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in addition to fuel and heat, what element must be present for fire to …
Oxygen
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chapter 23 4. learning to adapt to a variety of situations in daily lif…
4. B. coping 5. D. psychiatric 6. A. psychiatric 7. A. Social disturbance 8. C. inadequate blood flow to the brain
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7. what factor determines the path a star will take in its post - main …
mass
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the equation for the ph of a substance is ph = -logh+, where h+ is the …
8.7 (corresponds to the third option)
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solid sodium oxide and gaseous water are formed by the decomposition of…
\(2NaOH(s) ightarrow Na_2O(s)+H_2O(g)\)
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the following chemical reaction takes place in aqueous solution: fe(no₃…
$$\ce{Fe^{2+}(aq) + S^{2-}(aq) \to FeS(s)}$$
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a chemist adds 305.0 ml of a 3.79 mol/l potassium iodide (ki) solution …
\(0.193\space kg\)
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9. ___br₂ + ___nacl → ___na + ___br²cl²
\(1Br_2 + 2NaCl ightarrow2Na + 1Br_2Cl_2\)
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7. __ al₂s₃ → __ al + __ s 1 al₂s₃ → 2 al + 3 s
\(1Al_2S_3 ightarrow2Al + 3S\)
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6. ___ hgo → ___ hg + ___ o
\(2HgO ightarrow 2Hg+O_2\)
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5. __ mg + __ n→ __ mg^{+2}n^{-3} 3 mg + 2 n→ 1 mg_{3}n_{2}
\(3Mg+2N ightarrow1Mg_3N_2\)
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4. _ al + _ s → _ al₂s₃
\(2Al+3S ightarrow Al_2S_3\)
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3. __ na + __ cl₂ → __ na⁺¹cl⁻¹
\(2\text{Na}+\text{Cl}_2 ightarrow 2\text{NaCl}\)
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2. __ mg + __ f₂ → __ mg^{+2}f₂
\(1\) \(Mg+1\) \(F_2 ightarrow1\) \(MgF_2\)
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part 1: synthesis reactions 1. _ na + _ o₂ → _ na₂o 4 na + 1 o₂ → 2 na₂o
\(4Na+O_2 ightarrow2Na_2O\)
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12. agno₂ + mgcl₂ → mg(no₂)₂ + agcl
\(2AgNO_3 + 1MgCl_2 ightarrow1Mg(NO_3)_2+2AgCl\)
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14. __ c₂h₂ + __ o₂ → __ co₂ + __ h₂o
\(2C_{2}H_{2}+5O_{2} ightarrow4CO_{2}+2H_{2}O\)
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part 5: combustion reactions 13. _ ch₈ + _ o₂ → _ co₂ + _ h₂o
\(1CH_8+3O_2 ightarrow1CO_2 + 4H_2O\)
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11. _ baf₂ + _ k₃po₃ → _ kf + _ ba₃(po₃)₃
\(3BaF_2+2K_3PO_3 ightarrow6KF + Ba_3(PO_3)_2\)
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part 4: double replacement reactions 10. __rboh + __licl → __li(oh) + _…
\(1RbOH + 1LiCl ightarrow1LiOH + 1RbCl\)
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5. patients in cardiogenic shock should not receive: a. oxygen b. posit…
5. D. nitroglycerine 6. D. Tension pneumothorax 7. D. Release of norepinephrine 8. C. Hemoglobin 9. B. Cardiogenic shock
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find the element:
H
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air pollution global agreements several laws have evolved to address ai…
the United States
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a scientist is conducting an investigation that involves water, silver,…
They are each made of matter. Some are compounds and some are elements. They all contain atoms.
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fill out the table below based on the following chemical equation: nh3 …
| | \(Cl\) | \(H\) | \(N\) | |--|--|--|--| | **Total # Before (reactants)** | 1 | 4 | 1 | | **Total # After (products)** | 1 | 4 | 1 | Coefficients: \(1NH_3 + 1HCl ightarrow1NH_4C…
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question 5 of 10 read these lines from emily dickinsons poem \435\ (\mu…
C. abab
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use the periodic table to determine which of the following could be an …
B. \(Z = 35,A = 79\), C. \(A = 79,N = 44\)
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protons: neutrons: electrons: what is the mass number? 0
1
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a precious metal is a. an element with super and electric and thermal c…
B. a highly sought after dense, shiny, soft precious metal that has been used as money for many centuries.
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which of the following is not true of silver? a. it has the highest ele…
C. It is a copper alloy, usually mixed tin as the main additive.
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which of the following is true of iron? a. it has the highest electrica…
B. It can exist in many alloys, usually with a carbon base.
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read the paragraph, and then complete the model. fossil fuels are subst…
Atmosphere; Biosphere
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read the excerpt from \how we entered world war i\. in the midst of it …
show the reader that Germany was a legitimate threat to the United States
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which property is best to use when determining the strength of an ionic…
lattice energy
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which property best indicates that a compound contains an ionic bond? i…
It conducts electricity when molten.
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which statement is true about ionic compounds? they are made up of a ra…
They are made up of particles that are arranged in a repeating pattern.
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a lithium atom has three protons, three neutrons, and three electrons. …
0
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4. how many protons, electrons, and neutrons are in each of the followi…
a. Protons: 92, Electrons: 92, Neutrons: 143 b. Protons: 1, Electrons: 1, Neutrons: 2 c. Protons: 14, Electrons: 14, Neutrons: 15
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3. name each isotope, and write it in symbolic notation. a. atomic numb…
a. Name: iron - 56; Symbolic notation: \(\ce{^{56}_{26}Fe}\) b. Name: copper - 64; Symbolic notation: \(\ce{^{64}_{29}Cu}\) c. Name: chlorine - 37; Symbolic notation: \(\ce{^{37}_…
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molecular formula\tmolecule name pbr₃ scl₄ n₂f₂ so₃ brf 18. write molec…
| Molecular Formula | Molecule Name | |---|---| | \(PBr_{3}\) | phosphorus tribromide | | \(SCl_{4}\) | sulfur tetrachloride | | \(N_{2}F_{2}\) | dinitrogen difluoride | | \(SO_{3…
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how do an ionic bond and a covalent bond differ? an ionic bond is an at…
- Question 1: An ionic bond is an attraction between oppositely charged ions. A covalent bond is a sharing of electrons between atoms. - Question 4: the arrangement and types of a…
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how do an ionic bond and a covalent bond differ? an ionic bond is an at…
First question: An ionic bond is an attraction between oppositely charged ions. A covalent bond is a sharing of electrons between atoms. Second question: the arrangement and types…
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question 73 (1 point) during her pregnancy, emily should avoid all of t…
C. drinking tap water
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what is a bond between a positive and a negative ion called? metallic b…
- Question 1: ionic bond - Question 2: a bond between two atoms - Question 3: An ionic bond is an attraction between oppositely charged ions. A covalent bond is a sharing of elect…
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10. summarize the main points of the kinetic - molecular theory and how…
The kinetic - molecular theory's main points are: matter is composed of moving particles; particle motion varies with state (solid: vibration in fixed positions, liquid: more free…
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energy from the sun can be used instead of fossil fuels to produce elec…
A. It allows solar energy to be used to produce electricity at night.
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7. describe phase changes such as melting, freezing, vaporization, cond…
## Question 7: Melting: solid to liquid. Freezing: liquid to solid. Vaporization: liquid to gas. Condensation: gas to liquid. ## Question 8: Law of Conservation of Mass: mass is c…
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11 multiple choice 1 point which of the following explains why liquids …
Solids have strong forces that hold the particles together.
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tree roots can break down rock into soil. which type of weathering is t…
Physical
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question 55 (1 point) patrick is going to begin chemotherapy to treat a…
D. nausea, fatigue, and hair loss
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question 54 (1 point) jeremy was told that his leukemia could not be tr…
C. not localized.
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16 fill in the blank 1 point a cation is a choose your answer... charge…
16. positively 17. Chromium ion (or $Cr^{2+}$)
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13 fill in the blank 1 point an anion is a charged ion. 14 numeric 1 ho…
13. negatively 14. 11 15. sodium
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question 51 (1 point) leo died when a bulging cerebral blood vessel rup…
B. a hemorrhagic stroke.
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8 multiple choice 1 point which of these is a compound? shaving cream i…
NaCl ### Question 9
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electrons are choose your answer... other electrons. 7 matching 1 point…
Neutron - 1 amu, Electron - 0 amu, Proton - 1 amu
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3 numeric 1 point how many protons does cu²+ have? answer 4 multiple ch…
\(29\) ### Question 4
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a potassium atom has 20 neutrons. what is the mass number of the atom? …
$39$
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4. what is the difference between a physical property and a chemical pr…
- **Question 4**: Physical property: observed without chemical change (e.g., water's boiling point). Chemical property: describes chemical change ability (e.g., iron rusting). - *…
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2. define matter and describe the different states of matter. 3. compar…
- Matter is defined as anything with mass and space - occupying. States: solid (fixed shape/volume, low - energy, ordered particles), liquid (definite volume, takes container shap…
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21-lors dune réaction chimique, on utilise 100 g de vinaigre, que lon p…
a) \(310\) g b) \(309\) g
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physical change □ evaporating □ melting □ blowing □ evaporating □ teari…
Physical Change: evaporating, melting, blowing, tearing, cutting, condensing, breaking, dissolving, freezing. Chemical Change: burning, rusting, decomposing, reacting, corroding, …
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compare chemical changes and physical changes a. define and give an exa…
a. A physical change alters physical properties without changing chemical composition. Example: Ice melting (\(H_2O(s) ightarrow H_2O(l)\)). b. A chemical change converts substanc…
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based on the following balanced equation: mgo + 2hcl → mgcl₂ + h₂o how …
\(2\)
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based on the following balanced equation: ch₄ + 2o₂ → co₂ + 2h₂o how ma…
\(3\)
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based on the following balanced equation: 2h₂ + o₂ → 2h₂o how many mole…
\(8\)
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based on the following balanced equation: 3rb + p → rb₃p how many moles…
\(4\)
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based on the following balanced equation: 2h₂s + 3o₂ → 2so₂ + 2h₂o how …
\(6\)
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interpreting the question the given is 5.0 mol nal and the unknown is m…
\(2.5\space mol\space I_2\)
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interpreting the question the given is the balanced equation is br₂ + 2…
\(\frac{5.0\space mol\space NaI}{x\space mol\space I_{2}}=\frac{2\space mol\space NaI}{1\space mol\space I_{2}}\)
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interpreting the question the overall question is mathrm{br}_{2}+2 math…
mol \(I_2\)
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model 2 - prefixes and suffixes 5. examine the prefixes in model 2. fil…
5. mono - \(1\); di - \(2\); tri - \(3\); tetra - \(4\); penta - \(5\); hexa - \(6\); hepta - \(7\); octa - \(8\); nona - \(9\); deca - \(10\) 6. - ide 7. When the first element i…
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interpreting the question lets walk through the process to solve the qu…
\(5.0\ mol\ NaI\)
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1. what did jj thompson discover about electrons? a. they are positivel…
1. b. They are a tiny piece of every atom 2. b. By observing alpha particles bouncing off gold foil 3. b. Investigating X - ray patterns 4. b. It revealed that atoms are mostly em…
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question 1 8.33 pts br₂ (l) + nal (aq) → nabr (aq) + i₂ (s) total ionic…
- total ionic equation: $\text{Br}_{2}(l)+2\text{Na}^{+}(aq)+2\text{I}^{-}(aq)\to 2\text{Na}^{+}(aq)+2\text{Br}^{-}(aq)+\text{I}_{2}(s)$ - spectator ions: $\text{Na}^{+}$ - net io…
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here is a description of lithium from the periodic table. a) what does …
A) The number of protons in a lithium atom. B) The atomic mass of lithium. C) Protons, neutrons, and electrons.
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model 1 - molecular compounds 1. fill in the table to indicate the numb…
1. | Molecular Formula | Number of Atoms of First Element | Number of Atoms of Second Element | |---|---|---| | \(ClF\) | \(1\) | \(1\) | | \(CO\) | \(1\) | \(1\) | | \(CO_{2}\) |…
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what best describes the role of chemical pesticides in ipm? it should o…
It should only be used as the last resort.
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directions: sort the following properties of molecular (covalent), ioni…
| IONIC COMPOUNDS | MOLECULAR COMPOUNDS (COVALENT) | METALLIC COMPOUNDS | |---|---|---| | Form crystals with repeating patterns, Higher melting and boiling points | Lower melting …
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descriptions man - made structures, features, and facilities viewed col…
built environment, natural environment, conservation, natural resources
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1. write the long - form electron configuration of the following elemen…
Boron (\(B\)), Phosphorus (\(P\)), Chlorine (\(Cl\)), Manganese (\(Mn\)), Arsenic (\(As\))
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part a if an automobile air bag has a volume of 11.9 l, what mass of na…
\(23.0\space g\)
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part a consider the chemical reaction: 2h₂o(l) → 2h₂(g) + o₂(g) what ma…
\(2.28\space g\)
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missed this? watch kcv. simple gas laws and ideal gas law, iwe: ideal g…
\(60.4\space g\)
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which biogeochemical cycle is the most affected by human activities suc…
carbon cycle
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passage 1 passage 2 how is the concept of solitude portrayed in both so…
Solitude is viewed as a source of strength.