Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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soil is a heterogeneous mixture. which of the following statements best…
B. It is unevenly mixed, so it does not have the exact same composition throughout the mixture.
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fresh lemonade is a murky yellow color. if you leave it sitting for a f…
B. suspension
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in carbonated water, when carbon dioxide bubbles are thoroughly mixed i…
B. solution
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which is a heterogeneous mixture with large particles? a solution b sus…
B. suspension
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butter is a mixture of proteins and fats that does not separate out whe…
B. colloid
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which type of mixture has varying sizes of particles that are large eno…
B. colloid
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select all that apply a mixtures can be separated using physical proper…
A. mixtures can be separated using physical properties, C. the components keep their physical properties
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which of the following statements about mixtures is false? select all t…
B. they are all mixed uniformly and have an even composition throughout, D. Substances must combine in specific proportions
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which of the following are mixtures? select all that apply a air b copp…
A. air, C. sand, D. tea
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what is the name of a heterogeneous mixture with large particles that w…
Suspension
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which property is not used to separate a mixture? a particle size b boi…
d. Light transmittance
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pick the word that best completes the following sentence. a _________ m…
A. homogeneous
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which of these combinations might make a compound most similar to water…
C. Fluorine and Hydrogen
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question 1 2 pts when ronald was conceived, one of his 23rd chromosomes…
sex; gender
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question 14 (1 point) anions are best described as ions with more proto…
- Question 14: ions with more electrons than protons - Question 15: have a positive charge
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question 14 (1 point) anions are best described as ions with more proto…
ions with more electrons than protons # Question 15
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question 12 (1 point) a reaction between an acid (hcl) and base (lioh) …
- Question 12: neutralization - Question 13: False
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question 10 (1 point) london dispersion forces are the weakest of the i…
- Question 10: True - Question 11: dehydration reaction
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water is a strongly polar molecule. think about the following household…
- First question: vegetable oil - Second question: True
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question 7 (1 point) what type of force bonds oxygen to hydrogen inside…
covalent
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question 7 (1 point) what type of force bonds oxygen to hydrogen inside…
covalent
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13. explain the difference between elements and compounds.
Elements are pure substances of one - atom type, unbreakable chemically. Compounds are formed by chemical combination of different elements in fixed ratios and can be chemically d…
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question 4 (1 point) match the condensed molecular formula with the nam…
\(-NH_2\) - 1. amino \(-PO_4^{2 - }\) - 5. phosphate \(-CO-\) - 2. carbonyl \(-OH\) - 4. hydroxyl \(-COOH\) - 3. carboxyl
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question 3 (1 point) a reaction in which an electron moves from one ato…
C. redox
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question 1 (1 point) which of the following substances would be conside…
C. tomato juice, pH = 5.3 # Question 2
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how does the organization of the periodic table help us identify possib…
Elements in the same group of the Periodic Table have similar chemical properties (due to same valence - electron count), so we can look at elements in the same group for possible…
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multiple choice question the largest ionization energy or electronegati…
A. top right
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multiple choice question atomic radius is largest in the ————————————— …
C. bottom left
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multiple choice question groups are a. vertical columns b. horizontal r…
A. Vertical columns
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multiple choice question nonmetals make up most of the periodic table. …
B. false
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multiple choice question the atomic number equals the number of a. elec…
D. protons
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use the references to access important values if needed for this questi…
\(Zn(s)+Ni^{2 +}(aq) ightarrow Ni(s)+Zn^{2 +}(aq)\)
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when the following equation is balanced properly under acidic condition…
The coefficients of \(SO_{4}^{2-}\), \(Mn^{2+}\), \(H_{2}SO_{3}\), \(MnO_{4}^{-}\) are \(5\), \(2\), \(5\), \(2\) respectively. Water appears as a reactant with a coefficient of \…
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mary is adding sugar and fats at high heat to create a firm glaze on th…
C. carmelizing
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paul is a baker who wants to improve his recipe for muffins because the…
C. butter to margarine
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when the following equation is balanced properly under basic conditions…
- Coefficients: \(1I_2 + 1NO_2^- ightarrow 2I^-+1NO_3^-\) - Water appears as a product with a coefficient of \(1\) - The element that is reduced is \(I\) (iodine)
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when the following equation is balanced properly under basic conditions…
- Coefficients: \(2\) (for \(Cl^-\)), \(1\) (for \(I_2\)), \(2\) (for \(I^-\)), \(1\) (for \(Cl_2\)) - Water appears as neither with a coefficient of \(0\) - The element oxidized …
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which items are organic? a. metal cans b. glass bottles c. old dish clo…
D. vegetable trimmings
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what is the purpose of the safety equipment? cut - resistant gloves ove…
- "to keep hands warm and protect from extremely cold food items" → freezer gloves - "to protect hands from harsh dish washing chemicals" → dish washing gloves - "to protect from …
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select the correct answer. what documents provide information about the…
C. Material Safety Data Sheets
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identify the species oxidized, the species reduced, the oxidizing agent…
species oxidized: \(Cr^{2+}\) species reduced: \(Cl_{2}\) oxidizing agent: \(Cl_{2}\) reducing agent: \(Cr^{2+}\) Electrons are transferred from \(Cr^{2+}\) to \(Cl_{2}\)
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identify the species oxidized, the species reduced, the oxidizing agent…
species oxidized: \(Cd\) species reduced: \(Fe^{3+}\) oxidizing agent: \(Fe^{3+}\) reducing agent: \(Cd\) Electrons are transferred from \(Cd\) to \(Fe^{3+}\)
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use the rules (in order) to assign oxidation numbers to each of the ele…
For \(HIO_3\): \(H = +1\), \(I=+5\), \(O=-2\) For \(N_2H_4\): \(N=-2\), \(H = +1\) For \(HBO_2\): \(H = +1\), \(B=+3\), \(O=-2\)
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use the references to access important values if needed for this questi…
Zinc: \(+2\), Chlorine: \(+1\), Sulfur: \(+2\)
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determine the oxidation state for each of the elements below. the oxida…
The oxidation state of carbon in \(H_2C_2O_4\) is \(+3\). The oxidation state of bromine in \(MgBr_2\) is \(-1\). The oxidation state of silicon in \(SiO_3^{2-}\) is \(+4\).
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what made crossing no - mans - land so deadly? * a. heavy forests and r…
B. Mines, barbed wire, and artillery fire
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what is a solution? any mixture of substances a mixture with only one t…
A mixture in which the molecules of one substance are evenly distributed within another substance.
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true/false 1. agriculture is not considered to be among the more danger…
1. False 2. False 3. False
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use the references to access important values if needed for this questi…
\(13.0\space g\) (rounded to three significant figures)
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use the references to access important values if needed for this questi…
\(ClO^{-}(aq)+H^{+}(aq) ightarrow HClO(aq)\)
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be sure to specify states such as (aq) or (s). if a box is not needed l…
$$Ba^{2+}(aq)+CO_3^{2 - }(aq)\to BaCO_3(s)$$
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the following molecular equation represents the reaction that occurs wh…
$$\text{Pb}^{2+}(aq)+2\text{Br}^-(aq)\to\text{PbBr}_2(s)$$
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question 247 ischemia of the myocardium may result in: aneurysm angina …
- **Question 247**: angina pectoris - **Question 248**: sanity during crimes - **Question 249**: voice box
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use the references to access important values if needed for this questi…
$$\text{Sn}(s)+\text{Cu}^{2 +}(aq)\to\text{Sn}^{2 +}(aq)+\text{Cu}(s)$$
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question 190 athero/sclerosis is a type of: coronary ischemia arteriosc…
- Question 190: Arteriosclerosis - Question 191: ventricles - Question 192: breath/measure/process
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write the net ionic equation for the following molecular equation. hbr …
\(F^{-}(aq)+H^{+}(aq)\to HF(aq)\)
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6. variations in the color of oceans are caused by a. varying structure…
d. light interacting with other materials in the water.
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solubility of ionic compounds classify each of the compounds as soluble…
sodium nitrate: soluble; barium iodide: soluble; copper(II) carbonate: not soluble
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solubility of ionic compounds classify each of the compounds as soluble…
copper(II) sulfate: soluble; cobalt(II) bromide: soluble; zinc acetate: soluble.
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question 13 (1 point) all of the following are recommended to help cosm…
B. Sensitize the skin to the irritant by exposing it to larger and larger amounts. # Question 14
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question 145 the word part axillo - means: ○ armpit ○ wrist ○ forearm ○…
- **Question 145**: armpit - **Question 146**: brain - **Question 147**: embolism
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question 8 (1 point) ____ is an allergic reaction created by repeated e…
B. Sensitization
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question 94 the medical term burs/itis literally means: ○ cartilage inf…
- Question 94: sac inflamed - Question 95: rumble - Question 96: Dacryoadenitis
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one - year - old ainsley learned the schema for trucks because his fami…
C. assimilation
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identify the type of chemical reaction background info a chemical react…
1. Double Replacement 2. Combustion 3. Decomposition 4. Synthesis 5. Single Replacement
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which of the following statements is true for real gases? choose all th…
As molecules increase in size, deviations from ideal behavior become more apparent at relatively high pressures. As attractive forces between molecules increase, deviations from i…
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use the references to access important values if needed for this questi…
\(1716\)
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compute the root - mean - square speed of h₂ molecules in a sample of h…
\(2161m/s\)
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for each element listed below, indicate if the element is a metal, a no…
- 63. Metal - 64. Non - metal - 65. Non - metal - 66. Semimetal - 67. Non - metal - 68. Metal - 69. Semimetal - 70. Metal - 71. Semimetal - 72. Metal - 73. Beryllium (\(Be\)) - 74…
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hydrogen and oxygen atoms are more stable when they form bonds in a mol…
water ($H_2O$)
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what type of bond would form between atoms of the following elements? c…
C. ionic
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31. which of the atoms of period 3 attracts a shared pair of electrons …
31. B. Chlorine 32. D. Nitrogen 33. B. Potassium 34. A. occupied principal energy levels 35. A. Chlorine 36. C. 7 37. D. number of valence electrons 38. A. small covalent atomic r…
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carbon has 4 valence electrons. hydrogen has 1 valence electron. how ma…
C. 4
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metals usually form ________ with non - metals. a covalent bonds b meta…
C. Ionic bonds
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which of the following statement(s) about chemical bonding are true? se…
A. Bonds are formed by valence electrons of interacting atoms, D. Bonding occurs to give both atoms a more stable electron configuration
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ionic bonds form between oppositely charged ______. enter the answer ch…
ions
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use the references to access important values if needed for this questi…
\(105.7\space atm\)
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ionic bonds form between oppositely charged _____.
ions
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in covalent bonds, atoms ________. a share electrons b transfer electro…
A. share electrons
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in covalent bonds, atoms ________. a share electrons b transfer electro…
A. share electrons
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44. the ionic radius compared to the atomic radius of the parent atom i…
- 44. (d) larger for negative ions and smaller for positive ions - 45. (d) outer electrons being farther form the nucleus - 46. (b) alkaline earth metals - 47. (d) loosely held va…
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four properties are listed below. match each property with the correct …
17. B. Electronegativity 18. A. Atomic Radius 19. C. Ionic Radius 20. D. Ionization Energy
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what do these two changes have in common? sauce burning on a stove sali…
Both conserve mass. Both are chemical changes.
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what do these two changes have in common? dust settling out of the air …
Both are only physical changes.
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an error has been detected in your answer. check for typos, miscalculat…
- Has the highest average molecular speed: \(0.219\) moles of \(He\) in a \(5.17L\) container at a temperature of \(425K\) and \(0.703\) moles of \(He\) in a \(5.20L\) container a…
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1. how many periods are on the periodic table? 2. how many groups are o…
1. 7 2. 18 3. Group 1 (alkali metals), Group 2 (alkaline earth metals), Group 17 (halogens) 4. Groups 3 - 12 5. Group 17 6. Group 1 7. Period 7 8. Groups 1 and 2 9. Group 18 10. P…
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classwork science materials mixture answer the following 1 a mixture ca…
1. B. False 2. A. True 3. B. False
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periodic table which of the following statements about the properties o…
A. An atomic emission spectrum occurs when an element in the gas state absorbs energy, and emits light which corresponds to the energies of specific electron transitions. C. The l…
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periodic table which of the following statements about the properties o…
A. An atomic emission spectrum occurs when an element in the gas state absorbs energy, and emits light which corresponds to the energies of specific electron transitions. C. The l…
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which property of water means that it resists changes in temperature? u…
High Specific Heat
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how many chiral carbons are there in the compound shown below? • your a…
1
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which of the following compounds exhibits a linear molecular geometry? …
\(CO_2\), \(BeF_2\)
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gina made a poster for plastic recycling week and included this informa…
- Gina should put "DNA" under "Natural." - Gina should put "rubber tires" under "Synthetic." - Gina should put "cellulose" under "Natural." - Gina should put "nylon" under "Synthe…
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which are the chiral carbons in d - ribose? use the labeled carbon numb…
2,3,4
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which of the following statements is true about the molecules shown bel…
The first molecule (a) is chiral, and the second molecule (b) is achiral.
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surface tension is the property of water in which... water tends to be …
water molecules at the surface tend to stick together.
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the types of bonds that hold water together surface tension adhesion hy…
Hydrogen Bonds
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sodium (na) boron (b) gallium (ga) carbon (c) tin (sn) chlorine (cl) sa…
- Same valence electrons as silicon (Si) and more protons than silicon (Si): Tin (Sn) - Same energy levels as silicon (Si) and more protons than silicon (Si): (No element in the g…
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question which everyday object is chiral? select the correct answer bel…
C. shoe
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how many chiral carbons are there in the compound shown below? ho - ch₂…
2