Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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exam - chapter 1 (environmental science) circle the best answer for eac…
1. b. Sustainability 2. b. The Pacific Ocean 3. a. The Tragedy of the Commons 4. d. The Tragedy of the Commons 5. a. Resource; b. Service; c. Service; d. Resource 6. a. A renewabl…
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unsaturated fats can be converted to saturated fats through which also …
hydrogenation; trans fats
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model 2 - results of alka - seltzer® experiment trial number of alka - …
6a. The number of Alka - Seltzer tablets. 6b. The final temperature of the final mixture. 7. Volume of vinegar (100.0 mL), room pressure (84 kPa), initial temperature of vinegar s…
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question 1 why do vinegar and oil separate in salad dressing? answer oi…
The oil in salad dressing is hydrophobic whereas the vinegar is hydrophilic.
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which statement best describes the octet rule? a. atoms combine to achi…
d. Atoms combine to achieve a full outer shell of electrons.
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which molecule is likely to be polar based on its lewis dot structure? …
C. H₂O
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16 which choice correctly identifies the energy transformation that pow…
A. thermal to mechanical to electrical
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an example of a chemical property of matter would be? lying tying a sho…
Paper Burning
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an heterogenous mixture means that the substance is: different green dy…
For the first question: Different For the second question: None of the given options are correct as lying and tying a shoe are not chemical properties of matter.
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a(n) homogenous mixture means its different pure similar yellow
C. Similar
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question 8 what are the two properties used to identify matter? height,…
B. Physical, Chemical
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fe (iron) can be found on the periodic table. iron is an example of a h…
B. Element
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vinegar is a liquid mixture of both ch₃co₂h and h₂. vinegar is an examp…
A. Homogeneous mixture
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a scientist uses an instrument to observe the pattern of molecules in a…
D. solid
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which of the following is an example of a heterogeneous mixture? iron c…
chicken noodle soup.
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you hold a beaker in your hands as a chemical reaction occurs. the beak…
B. Exothermic
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central ideas and details: foundations scent is tightly interwoven with…
B. They believe the scents could illuminate important aspects of ancient life.
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in order to speed up a chemical reaction, you should ______________ the…
Lower
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unit 1, classwork #3 - mole conversions use dimensional analysis to sol…
$1.2044 \times 10^{24}$ atoms
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a word written over the arrow in a chemical reaction equation indicates…
None of the above options are correct.
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1. calculate the number of atoms in one mole of iodine.
1.2044×10²⁴
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a. a solution of two solids b. a mixture of particles with different de…
25. b 26. a
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which set lists the atomic models and scientists from the oldest (first…
X, Z, W, Y
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22. which of the following is not a pure substance? a. helium b. carbon…
22. c. Seawater 23. c. 41
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22. which of the following is not a pure substance? a. helium b. carbon…
c. Seawater ### 23.
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22. which of the following is not a pure substance? a. helium b. carbon…
c. Seawater ### 23.
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17. which of the following is a heterogeneous mixture? a. air b. soil c…
17. b. soil 18. c. 225g 19. a. Its mass and volume decrease. 20. d. oil and vinegar 21. b. salt water
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17. which of the following is a heterogeneous mixture? a. air b. soil c…
17. b. soil ## Step1: Apply law of conservation of mass The total mass of water in the cup before melting (125 g liquid water + 100 g ice) is 225 g. During the phase change from i…
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10. in a chemistry lab, students were given an unlabeled substance and …
Substance B is most likely a compound because it can be separated into simpler substances.
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exam 1: atomic theory/structure possible points: 36 e7 fill out the fol…
| Isotope Name | Nuclear Symbol | Atomic Number | Mass Number | # of protons | # of neutrons | # of electrons | | ---- | ---- | ---- | ---- | ---- | ---- | ---- | | calcium - 40 |…
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7. which term means “a combination of two or more substances that keep …
7. b. mixture 8. c. liquid 9. d. volume 10. c. gas only 11. d. liquid only
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exam 1: atomic theory/structure possible points: 3.33 an isotope of oxy…
D. 18
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for a substance to change from a gas to a liquid, what must happen to i…
B. They must lose enough of their kinetic energy that their motion is influenced by the attractions between them.
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6. which of the following is considered a physical property of a substa…
b. malleability
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exam 1: atomic theory/structure how are different elements identified o…
the number of protons
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which two options are forms of kinetic energy? a. thermal energy b. gra…
A. Thermal energy, D. Sound energy
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1. a horizontal row of the periodic table is usually referred to as a a…
1. b. Period 2. a. solid 3. c. physical;chemical 4. a. A compound 5. d. hydrogen
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exam 1: atomic theory/structure which idea of daltons is no longer cons…
Atoms of the same element are all identical.
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exam 1: atomic theory/structure in jj thomsons experiment, ____________…
B. cathode ray tube, plum pudding
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exam 1: atomic theory/structure isotopes are atoms of the same element …
C. neutrons
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exam 1: atomic theory/structure how many protons does phosphorus - 31 c…
A. 15
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exam 1: atomic theory/structure if an atom has lost 2 electrons to beco…
+2 (corresponding to the fourth option)
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exam 1: atomic theory/structure how many neutrons does zinc - 70 contai…
40 (corresponds to the second option)
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exam 1: atomic theory/structure for an atom to be electrically neutral,…
C. protons and electrons
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question 10 (1 point) listen isotopes are atoms of same element which c…
4) More neutrons as compared to other atoms of the same substance
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exam 1: atomic theory/structure silicon - 30 contains 14 protons. how m…
D. 14
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you turn on a light in a room to read a book. not all the energy from t…
A. It is transformed into thermal energy.
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exam 1: atomic theory/structure what is the nuclear composition of uran…
D. 92 protons + 143 neutrons
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exam 1: atomic theory/structure atoms that have unequal amounts of prot…
B. ions
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question 4 (1 point) listen an atom of an element has 10 protons. there…
3) Equal to 10
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which of the following is biochemistry? 1) study of medicines 2) study …
2) Study of chemical processes that occur in living systems
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exam 1: atomic theory/structure which best describes the current (quant…
Atoms are composed of electrons in a cloud around a positive nucleus.
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question 1 (1 point) listen chemistry is called central science because…
1) True
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isotope2. different isotopes of the same element must have different __…
D. numbers of neutrons, E. mass numbers
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question 9 (1 point) listen elementname1. which element has the symbol …
C. iron
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question 8 (1 point) charge3. how many electrons are in a ti⁴⁺ ion? 20 …
B. 18
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violet has noticed that shes been feeling sick around one of the chemic…
Yes
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question 7 (1 point) charge1. how many electrons are in a cu²⁺ ion? 65 …
B. 27
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question 6 (1 point) listen particle7. the position of an atom in the p…
the number of protons in the atom
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question 5 (1 point) massnumber3. how many neutrons are in a $^{60}co$ …
E. 33
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question 4 (1 point) listen symbol4. the symbol for the element chlorin…
D. Cl
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question 3 (1 point) listen periodictable2. select all the correct stat…
B. It is in Group 2A, C. It is an alkaline earth metal
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question 2 (1 point) listen periodictable3. select all the correct stat…
It is in Group 3A. It tends to form a stable ion with a +3 charge.
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elementcompound4. select all the element(s) from the following substanc…
Si, Br₂
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count the significant digits in each of these measurements: measurement…
3 2 2 5
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check the box under each molecule in the table below that is an isomer …
Check the boxes under all four molecules in the table (the four molecules with chemical structures shown). Do not check the "none of the above" box.
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measurements show that unknown compound x has the following composition…
$Cr_2O_3$
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determine the relationship between structure a and structure b in each …
1. Isomers 2. Isomers 3. Isomers
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reactivity quick check which elements would react most easily with each…
an element with a high electronegativity and an element with a single valence electron
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1. multiple choice 1 point when a mother walks into a room and sees tha…
1. verbal 2. situational
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complete the following statement about the earth system. matter is cont…
light waves
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66. as urban environments become denser, noise pollution is becoming a …
## Question 66: E ## Question 67: B ## Question 68: A
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8. what volume would 23.82 grams of mercury occupy? $\frac{23.82}{v}=13…
$1.75$ cm³
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this element is directly below the element that has 49 protons in its n…
Holmium (Ho), Moscovium (Mc), Selenium (Se), Ytterbium (Yb), Nihonium (Nh), Germanium (Ge), Flerovium (Fl), Gallium (Ga), Cesium (Cs), Indium (In), Arsenic (As), Radon (Rn), Tin (…
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this element is directly below the element that has 49 protons in its n…
1. Holmium (Ho) 2. Moscovium (Mc) 3. Selenium (Se) 4. Ytterbium (Yb) 5. Nihonium (Nh) 6. Germanium (Ge) 7. Flerovium (Fl) 8. Gallium (Ga) 9. Cesium (Cs) 10. Indium (In) 11. Arseni…
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this element is directly below the element that has 49 protons in its n…
Indium (In), Moscovium (Mc), Selenium (Se), Polonium (Po), Nihonium (Nh), Germanium (Ge), Flerovium (Fl), Gallium (Ga), Cesium (Cs), Arsenic (As), Radon (Rn), Tin (Sn)
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this element has one more proton than caesium (cs). this element has 8 …
1. Barium (Ba) 2. Oxygen (O) 3. Chlorine (Cl) 4. Astatine (At) 5. Bismuth (Bi) 6. Boron (B) 7. Phosphorus (P) 8. Aluminium (Al) 9. Nitrogen (N) 10. Silicon (Si) 11. Carbon (C) 12.…
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this element is directly below the element that has 56 protons. this el…
Radium (Ra), Carbon (C), Francium (Fr)
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the atomic number of this element is 82. this element is directly below…
Lead (Pb)
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this element has 1 less proton than polonium (po) in its nucleus. the a…
Lead (Pb)
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the small object in the picture is an artifact from anglo - saxon engla…
part of a ring
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this element is directly above the element with 13 protons. the atomic …
Based on the above - mentioned identifications for each statement: 1. Boron (B) 2. Phosphorus (P) 3. Magnesium (Mg) 4. Gallium (Ga) or Indium (In) 5. Aluminum (Al) 6. Chlorine (Cl…
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this element has 113 electrons surrounding its nucleus
Nihonium (Nh)
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clue this element has 9 more electrons than technetium (tc) this elemen…
Tl, Mc, At, Po, Ge, Al, Ga, Cs, C, Pb, Rn, Sn
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find the hidden element hidden in each group of letters below is the na…
1. Name: Nitrogen, Symbol: N, Number: 7 2. Name: Carbon, Symbol: C, Number: 6 3. Name: Sulfur, Symbol: S, Number: 16 4. Name: Calcium, Symbol: Ca, Number: 20 5. Name: Iodine, Symb…
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question 7 1 pts the number of protons in the nucleus of an atom is its…
D. Z
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question 5 1 pts which of the following subatomic particles is located …
Question 5: D. electrons Question 6: A. neutron, B. proton
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question 1 1 pts atoms are composed of which three subatomic particles?…
- Question 1: neutrons, protons, electrons - Question 2: atomic mass unit
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question 14 1 pts given the following symbol, the atomic number is _, t…
Question 14: B. 12, 24, 2+ Question 15: D. isotopes
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question 12 1 pts the symbol for a mercury atom or for a bottle contain…
Question 12: C. Hg Question 13: True
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question 10 1 pts the atomic charge is equal to number of neutrons + nu…
Question 10: number of protons - number of electrons Question 11: anion, cation
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the total number of protons and neutrons in an atom is called its mass …
First question: A. A Second question: number of protons + number of neutrons
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a childrens cough syrup contains 25.0 mg of benzocaine (a numbing agent…
14.5 mL ### Question 2
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a molecule of hydrogen moves at a speed of 115 cm/s. how long will it t…
79.5 s ### Question 2
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the density of liquid gold (au) is 19.3 g/cm³. if given a mass of 29.2 …
1.51 L
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question 5 (start on a new page) sulphuric acid is a strong acid and re…
5.1: An acid that can donate two protons per molecule in successive ionization steps. 5.2: $HSO_4^-$ 5.3: Acid: $H_2SO_4$, Base: $HSO_4^-$ 5.4: $Na_2SO_4$ 5.5: Yellow 5.6.1: Stron…
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specify the number of protons (#p⁺), neutrons (#n⁰) and electrons (#e⁻)…
$\#p^+=30$ $\#n^0 = 34$ $\#e^-=30$
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specify the number of protons (#p⁺), neutrons (#n⁰) and electrons (#e⁻)…
$\#p^{+}:30$ $\#n^{0}:34$ $\#e^{-}:28$
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specify the number of protons (#p⁺), neutrons (#n⁰) and electrons (#e⁻)…
#p⁺: 8 #n⁰: 8 #e⁻: 10
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for each set of subatomic particles specify the atom as neutral, cation…
1. neutral 2. anion 3. cation 4. cation 5. anion