化学
化学反応、化学量論、分子構造、元素の性質。
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select the subatomic composition of a vanadium ion (v⁵⁺) with a mass nu…
23 protons, 28 neutrons, 18 electrons
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select the subatomic composition of an iron(iii) ion (fe³⁺) with a mass…
26 protons, 30 neutrons, 23 electrons
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select the subatomic composition of a strontium ion (sr²⁺) with a mass …
38 protons, 50 neutrons, 36 electrons
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select the subatomic composition of a rubidium - 85 atom. refer to a pe…
37 protons, 48 neutrons, 37 electrons
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select the subatomic composition of a zirconium - 90 atom. refer to a p…
40 protons, 50 neutrons, 40 electrons
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select the subatomic composition of a selenium - 80 atom. refer to a pe…
34 protons, 46 neutrons, 34 electrons
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a hydrogen - 1 atom is an isotope of hydrogen (h) with a mass number of…
1 proton, 0 neutrons, 1 electron
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this is a bohr model of an atom or ion. select the nuclear notation tha…
$^{14}_{7}N$
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this is a bohr model of an atom or ion. select the nuclear notation tha…
$_{4}^{9}\text{Be}$
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this is a bohr model of an atom or ion. select the nuclear notation tha…
$_{3}^{6}\text{Li}^+$
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a simple constant - pressure calorimeter can be made from a foam coffee…
$906\ kJ/mol$
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hydrazine (n₂h₄) is a fuel used by some spacecraft. it is normally oxid…
$-514.7$
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consider the thermochemical equation for the combustion of acetone (c₃h…
$3910$
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kidney stones form when excess molecules have been excreted. when urine…
All of the above
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calculate how much co₂ (in kg) is produced by world fossil fuel combust…
$4.0\times10^{14}\ kg$
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the half life of iodine - 131 is 8.10 days. how much of a 200 - gram sa…
C. 25 grams
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question 17 (2 points) saved write the predicted electron configuration…
1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s²4d¹⁰5p⁶6s²4f¹⁴5d¹⁰6p⁶7s²5f⁴6d¹
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question 15 (4 points) saved calculate the average atomic mass of imagi…
$145.71$ amu (rounded to two decimal places)
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question 8 (3 points) calculate the percentage of chlorine in 41.7 g of…
The percentage of chlorine is approximately 47.5%
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question 7 (2 points) how many atoms of each element are present in one…
Fe: 2 atoms, S: 3 atoms, O: 12 atoms
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question 13 (4 points) write the following element in atomic notation b…
Chemical Symbol: $Pm$ Atomic Number: 61 Mass Number: 145 Charge: +2
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question 12 (3 points) state the element, the mass number, the atomic n…
Blank # 1: Germanium Blank # 2: 72 Blank # 3: 32 Blank # 4: 32 Blank # 5: 40 Blank # 6: 34
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which scientist discovered the nucleus of the atom? chadwick thomson da…
D. Rutherford
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question 14 (1 point) how many neutrons exist in bohrium - 269? only wr…
162
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question 16 (1 point) elements found in the inner transition metals fil…
B. f - level
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question 18 (1 point) what element is represented by the following elec…
Thallium
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question 19 (1 point) how many valence electrons does the element galli…
3
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question 21 (1 point) which of the following elements has the highest i…
Nitrogen
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question 22 (2 points) state four ions that are isoelectronic to neon i…
Blank #1: $N^{3 - }$ Blank #2: $O^{2 - }$ Blank #3: $Na^{+}$ Blank #4: $Mg^{2+}$
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question 23 (1 point) suppose a new element z was just discovered to be…
-2
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question 26 (3 points) state whether each bond is ionic, polar covalent…
Hydrogen and Chlorine: 2. Polar Covalent Potassium and Bromine: 1. Ionic Carbon and Oxygen: 2. Polar Covalent Nitrogen and Nitrogen: 3. Non - polar Covalent Hydrogen and Sulfur: 2…
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question 27 (1 point) which molecule shape has a bond angle of 120 degr…
C. Trigonal Planar
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question 10 (1 point) calculate the volume of a gas that has a density …
12 L
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question 6 (3 points) match each example with its correct type of chang…
- Dissolving salt in vinegar: 1. Physical Change - Cooking an egg: 2. Chemical Change - Fermentation of grape juice: 2. Chemical Change - Freezing of water: 1. Physical Change - S…
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question 3 (1 point) which element is in group 18 and period 3? neon (n…
- Question 3: B. Argon (Ar) - Question 4: D. Iodine (I) - Question 5: B. Metalloids
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match each substance with its correct classification: element, compound…
- Vegetable soup: 4. Heterogenous Mixture - Saltwater: 3. Homogenous Mixture - Carbon dioxide ($CO_2$): 2. Compound - Hydrogen: 1. Element - Iron: 1. Element - Concrete: 4. Hetero…
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a team led by portuguese researcher isabel c.f.r. ferreira found that m…
D. For example,
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modeling real life ph is measured on a scale of 0 to 14 and refers to t…
$7.2\leq pH\leq7.8$
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multiple choice question pigment molecules are embedded within the ____…
B. outer
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multiple choice question ____ are found within the aorta to help detect…
D. Chemoreceptors
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multiple choice question meissners corpuscles and merkel disks are clas…
B. touch
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multiple choice question meissners corpuscles and merkel disks are clas…
C. touch
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multiple choice question what is the name of the receptors that are sti…
Pain receptors
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multiple choice question which of the following is the type of receptor…
mechanoreceptor
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1. which instrument provided the most accurate and precise results? why…
1. Vernier calipers often provide more accurate and precise results due to finer scale divisions compared to rulers and tape measures. 2. Rulers and tape measures have larger leas…
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literary - text elements historical and social context directions: belo…
1. The setting with soldiers waiting for the enemy, being cold and hungry, indicates a war - time historical context of hardship and uncertainty. 2. It suggests a social context o…
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homework: chapter 6 exercise 6.99 the citizens of the world burn the fo…
$6.2\times10^{14}\ kg$
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19. complete the charts group numbers element type group description me…
| Group Numbers | Element Type | Group Description | | ---- | ---- | ---- | | 1, 2 | Metal | Reactive metals | | 17 | Non - metal | Very reactive non - metals | | 14 | Metalloid |…
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12. naturally - occurring element. it exists in three isotopic forms: 5…
12 - 15: Answers will depend on the specific values plugged into the average - atomic - mass and percent - abundance formulas. 16: Mendeleev arranged elements by atomic mass, Mose…
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14. the graph to the right shows part of the mass spectrum for a sample…
14. Insufficient data to calculate relative atomic mass and identify element. 15. Percent abundance of Ga - 69: \(60.3\%\), Percent abundance of Ga - 71: \(39.7\%\)
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11. fill in the following table. be careful, it contains atoms, ions an…
# Explanation: ## Step1: Recall atomic number properties The atomic number is equal to the number of protons. Given atomic number = 13, so number of protons = 13. Mass number = nu…
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1. fill in the following table. be careful, it contains atoms, ions and…
| Symbol | Atomic # | Mass # | # of Protons | # of Electrons | # of Neutrons | Net Charge | Cation/Anion | |---|---|---|---|---|---|---|---| | Al | 13 | 28 | 13 | 13 | 15 | 0 | At…
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10. how are uranium - 238 and uranium - 235 similar? different? 11. fil…
For question 10: Similarities: They are isotopes of uranium, so they have the same number of protons. Differences: They have different mass numbers and different numbers of neutro…
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9. decide if the following are isotopes (yes or no) ____no a) 8 protons…
a) yes b) no c) yes d) no e) yes 10. Similar: Same number of protons (92). Different: Different number of neutrons (146 in U - 238 and 143 in U - 235)
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10. a solution is 0.045 m h₂c₂o₄. determine the ph of the solution and …
$pH\approx1.82$, $[C_2O_4^{2 -}]=6.4\times 10^{-5}$ M
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consider the phosphorus tetrachloryl (pcl₄⁺) cation. what is the centra…
1. P 2. 0 3. $109.5$ 4. the same
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answer the questions in the table below about the shape of the sulfur h…
What word or two - word phrase best describes the shape of the $SF_6$ molecule? Octahedral What is the angle between the sulfur - fluorine bonds? (If there is more than one angle,…
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what are the angles a and b in the actual molecule of which this is a l…
\(a = 120\) \(b = 109.5\)
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what word or two - word phrase best describes the shape of the hydrogen…
Linear
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check the box next to each molecule on the right that has the shape of …
\(SO_3\)
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answer the questions in the table below about the shape of the trifluor…
How many electron groups are around the central nitrogen atom: 4 What phrase best describes the arrangement of these electron groups around the central nitrogen atom: tetrahedral
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answer the questions in the table below about the shape of the iodine p…
How many electron groups are around the central iodine atom? 6 What phrase best describes the arrangement of these electron groups around the central iodine atom? Octahedral
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a student proposes the following lewis structure for the nitrite (no₂⁻)…
| atom | formal charge | |--|--| | left O | - 1 | | N | 0 | | right O | 0 |
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draw the lewis structure for the phosphorus trichloride (pcl₃) molecule.
The Lewis structure has a central P atom with 1 lone - pair and single bonds to 3 Cl atoms. Each Cl atom has 3 lone - pairs around it.
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answer the questions in the table below about the shape of the ozone (o…
How many electron groups are around the central oxygen atom: 3 What phrase best describes the arrangement of these electron groups around the central oxygen atom: Trigonal planar
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answer the questions in the table below about the shape of the methyl (…
How many electron groups are around the central carbon atom: 3 What phrase best describes the arrangement of these electron groups around the central carbon atom: trigonal planar
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answer the questions in the table below about the shape of the carbon d…
How many electron groups are around the central carbon atom? 2 What phrase best describes the arrangement of these electron groups around the central carbon atom? Linear
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how many valence electrons are in the t - butyl ion (ch₃)₃c⁺?
24
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how many valence electrons are in the sulfur hexafluoride molecule sf₆?
48
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below is the lewis structure of the hydrazine (n₂h₂) molecule. h : n ::…
bonding pairs: 2 lone pairs: 2
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below is the lewis structure of the fluoramine (nh₂f) molecule. :f: h:n…
bonding pairs: 3 lone pairs: 1
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draw the lewis dot diagram for a neutral atom of ca.
Ca with 2 dots around it (one on the top and one on the side for example, but the placement of the two dots can vary as long as they are around the symbol).
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some soluble compounds are listed in the table below. complete the tabl…
| compound | name | type of compound (check all that apply) | | ---- | ---- | ---- | | $KCl$ | potassium chloride | ionic | | $HI$ | hydroiodic acid | molecular, strong acid | | $…
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name these ionic compounds: compound name cahpo₃ 0 mg(h₂po₃)₂ 0 mg(hco₃…
| compound | name | |--|--| | $CaHPO_3$ | calcium hydrogen phosphite | | $Mg(H_2PO_3)_2$ | magnesium dihydrogen phosphite | | $Mg(HCO_3)_2$ | magnesium bicarbonate (or magnesium h…
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write the chemical formula of each of the acids listed in the table bel…
| acid | chemical formula | |--|--| | iodic acid | $HIO_{3}$ | | phosphoric acid | $H_{3}PO_{4}$ | | nitrous acid | $HNO_{2}$ | | hydrosulfuric acid | $H_{2}S$ |
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name each of the acids listed in the table below. chemical formula name…
1. Phosphoric acid 2. Chlorous acid 3. Hydrosulfuric acid 4. Perbromic acid
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classify each chemical compound listed in the table below. compound typ…
| compound | ionic | molecular | acid | base | | ---- | ---- | ---- | ---- | ---- | | NaBrO₃ | $\checkmark$ | $\square$ | $\square$ | $\square$ | | H₃PO₄ | $\square$ | $\checkmark…
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the periodic table of elements identify the atomic symbol for carbon. a…
A. C
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identify the atomic symbol for nitrogen. a n b na c ne d ni
A. N
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the periodic table of elements identify the atomic symbol for potassium…
B. K
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the periodic table of elements give the name of the element that is rep…
D. Oxygen
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in the chemical reaction that forms table salt (nacl), which two elemen…
D. Sodium and chlorine
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which two atoms must combine to form methane (ch₄)? a carbon and helium…
B. Carbon and hydrogen
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a reaction between two elements forms ki. which elements are present in…
B. Potassium and iodine
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an unidentified pure solid is composed of an element. the substance is …
C. on the left side of the periodic table
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fill in the name and empirical formula of each ionic compound that coul…
| cation | anion | empirical formula | name of compound | | ---- | ---- | ---- | ---- | | $Mg^{2+}$ | $NO_{3}^{-}$ | $Mg(NO_{3})_{2}$ | magnesium nitrate | | $Na^{+}$ | $PO_{3}^{3…
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fill in the name and empirical formula of each ionic compound that coul…
| cation | anion | empirical formula | name of compound | | ---- | ---- | ---- | ---- | | $Na^+$ | $BrO_4^-$ | $NaBrO_4$ | sodium perbromate | | $Na^+$ | $BrO_3^-$ | $NaBrO_3$ | s…
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fill in the name and empirical formula of each ionic compound that coul…
| cation | anion | empirical formula | name of compound | | ---- | ---- | ---- | ---- | | $Na^+$ | $NO_3^-$ | $NaNO_3$ | sodium nitrate | | $Pb^{4+}$ | $OH^-$ | $Pb(OH)_4$ | lead(…
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complete this table. | name | empirical formula | |--|--| | chromium (i…
| name | empirical formula | |--|--| | chromium (II) fluoride | $CrF_{2}$ | | rubidium oxide | $Rb_{2}O$ |
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fill in the name and empirical formula of each ionic compound that coul…
| cation | anion | empirical formula | name of compound | | ---- | ---- | ---- | ---- | | $Mn^{3+}$ | $S^{2 -}$ | $Mn_2S_3$ | manganese(III) sulfide | | $Pb^{4+}$ | $O^{2 -}$ | $P…
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fill in the name and empirical formula of each ionic compound that coul…
| cation | anion | empirical formula | name of compound | | ---- | ---- | ---- | ---- | | Sn²⁺ | O²⁻ | SnO | tin(II) oxide | | Mn³⁺ | P³⁻ | MnP | manganese(III) phosphide | | Fe³⁺…
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fill in the name and empirical formula of each ionic compound that coul…
| cation | anion | empirical formula | name of compound | | ---- | ---- | ---- | ---- | | $K^+$ | $S^{2 -}$ | $K_2S$ | potassium sulfide | | $Mg^{2+}$ | $I^-$ | $MgI_2$ | magnesiu…
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fill in the name and empirical formula of each ionic compound that coul…
| cation | anion | empirical formula | name of compound | | ---- | ---- | ---- | ---- | | Mg²⁺ | O²⁻ | MgO | magnesium oxide | | Sr²⁺ | S²⁻ | SrS | strontium sulfide | | Rb⁺ | Br⁻…
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fill in the systematic names of the following chemical compounds. note:…
| molecular formula | name of compound | | ---- | ---- | | $C_3S_2$ | tricarbon disulfide | | $BP$ | boron phosphide | | $CS_2$ | carbon disulfide | | $BI_3$ | boron triiodide | |…
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10 sort the characteristics into which state change they describe. liqu…
Liquid to solid: Molecule vibration decreases, Molecules begin to stick together, Energy within the substance decreases Solid to liquid: Molecule vibration increases, Molecules ar…
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complete the table below. some binary molecular compounds name\tchemica…
| name | chemical formula | |--|--| | carbon tetrafluoride | $CF_4$ | | nitrogen trifluoride | $NF_3$ | | dinitrogen tetrafluoride | $N_2F_4$ | | chlorine monofluoride | $ClF$ |
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8 the molecules in the liquid water begin to move faster and faster all…
1. Energy in the form of heat is added to a pot of room - temperature liquid water. 2. The molecules in the liquid water begin to move faster and faster. 3. Steam forms as the att…
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ferdinand tonnies would view hunting - and - gathering societies as exa…
A. Gemeinschaft
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arrange the highlighted bonds in the table below in decreasing order of…
H—F: 1 H—Br: 2 H—I: 3
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question 10 0.5 pts on your certified organic farm, you grow a variety …
Start selling your seasoning mixes to the public at farmers' markets in the area.