化学
化学反应、化学计量、分子结构与元素性质。
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galactose. compare glucose, fructose, and galactose. select the true st…
Glucose, fructose, and galactose are monosaccharides. All three molecules have six carbon atoms.
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carbohydrates are also known as saccharides. the word saccharide is a t…
$C_6H_{12}O_6$
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question 5 which step determines the overall reaction rate? the first s…
the slowest step
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question 4 which of the following is true about activated complexes? th…
They exist only during the transformation of reactants to products.
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15 the nitrogen cycle key question what processes are involved in the c…
(a) Nitrogen - fixing; $N_2$ to $NH_4^+$ (b) Ammonification; Organic nitrogen to $NH_4^+$ (c) Nitrification (first step); $NH_4^+$ to $NO_2^-$ (d) Nitrification (second step); $NO…
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question 3 what is a reaction intermediate? a substance that appears in…
A substance that is produced by an early step and consumed in a later step.
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question 2 the steps in a reaction mechanism are called ______ reaction…
A. elementary
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question 1 a reaction mechanism is the balanced equation representing a…
The step - by - step sequence of elementary processes during a chemical reaction.
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electrons part 1: vocabulary - fill in the blank use the word bank to c…
1. electrons 2. nonpolar covalent 3. ionic 4. polar covalent 5. metal; nonmetal 6. share
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the grey antenna - shaped molecules in this image are ____________ rece…
opioid; brain
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question 15 (1 point) q15 - find the group 16 gas oxygen fluorine neon …
A. Oxygen
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question 13 (1 point) q13 - find the period 2 solids li, be, b, c na, m…
Question 13: Li, Be, B, C Question 14: Fluorine & Chlorine
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question 11 (1 point) q11 - find the 5th period non - transition elemen…
## Question 11: Rb, Sr, In, Sn, Sb, Te, I, Xe ## Question 12: Promethium
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question 9 (1 point) q9 - find the liquid in group 17 mercury tungsten …
Question 9: D. Bromine Question 10: C. Neptunium
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q7 - find the actinide with highest atomic mass plutonium hydrogen uran…
Q7. D. Lawrencium Q8. D. Boron
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question 7 (1 point) q7 - find the actinide with highest atomic mass pl…
Q7. D. Lawrencium Q8. D. Boron
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q5 - find the alkaline earth metal in 6th period magnesium calcium radi…
Q5. D. Barium Q6. A. Argon
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question 3 (1 point) q3 - find the rare earth metal with lowest atomic …
Q3. Scandium Q4. Manganese
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q1 - find the alkali metal in the 4th period phosphorus oxygen potassiu…
Q1. C. Potassium Q2. C. Chlorine
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there are four sketches below. the first sketch shows a sample of subst…
Change 1 is: a physical change Change 2 is: a physical change Change 3 is: a chemical change
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6. according to information in “physical changes,” what is matter made …
6. b. Matter is made of tiny particles called atoms 7. c. Rust is caused when iron reacts with water and oxygen 8. b. Chemical changes can be reversed 9. a. The glossary 10. c. wa…
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directions: use the information in the two - passages physical changes …
1. b 2. c 3. d 4. c 5. d
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persuasive language lets focus on logos logos is an appeal to logic; it…
Task One: 1. Effective. 2. Not effective. 3. Effective. 4. Effective. 5. Not effective. Task Two: 1. Chocolate is high in sugar; the American Heart Association states excess sugar…
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part c: electron configuration 12. how many electrons can each level ho…
For Sulfur: Protons = 16, Neutrons = 16, Electrons = 16. For Lithium: Protons = 3, Neutrons = 4, Electrons = 3. For Neon: Protons = 10, Neutrons = 10, Electrons = 10. For Magnesiu…
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atomic basics part a: atomic structure 1. draw five protons in the nucl…
6. Symbol: O, Element Name: Oxygen, Atomic Mass: 15.999 7. The atomic number represents the number of protons (or electrons in a neutral atom). 8. The atomic mass represents the s…
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1 mol ti₆al₄v contains mol ti.
6
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part 1 chromium is most commonly mined in the form of chromite, which h…
%Fe = 24.95% %Cr = 46.45% %O = 28.60% Part 2: 80.42 g
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05 question (1 point) coast tutorial problem tennantite is an ore of co…
23.44 (rounded to two decimal places)
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question 5 (1) what does the atomic packing factor represent? the fract…
The atomic packing factor represents the fraction of volume in a unit cell that is occupied by atoms or ions. For the second part, without a proper calculation method for the give…
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2. explain why the solution was heated. 3. list two reasons why the cal…
5. Solute: salt; Solvent: water 6a. Filtration
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percent salt (mass of salt ÷ mass of mixture)x100 46.5 percent sand (ma…
1. Incomplete dissolution of salt, leaving some salt mixed with sand. 2. Loss of salt due to spattering during heating/evaporation.
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how many moles of copper are present in a sample of tennantite with a m…
45.5
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a silicon wafer with dimensions 19.00 cm×19.00 cm×0.0500 cm contains 1.…
$42.1\ g$ (rounded to 3 significant figures)
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which of these images shows a homogeneous mixture?
The image with the creamy liquid in a glass (third option).
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consider the following situation: a scientist is given an unknown mater…
It is probably a chemical element, like gold
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evaluate this statement: two substances that are physically combined wi…
A. Sometimes True
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02 question (6 points) a chemical formula contains information about th…
Part 1: 1 mol N and 3 mol H Part 2: $Al_2O_3$ Part 3: 6 mol Ti, 4 mol Al, 1 mol V
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which of these is not a method of combining matter? * mixture addition …
B. Addition
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evaluate this statement: two substances that are combined will form a c…
The statement is false. Combining two substances may form a mixture (physical combination) instead of a compound (chemical combination with fixed proportions).
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1. write the balanced chemical equation and the kₑ expression for the f…
a. Balanced equation: $Cu(s)+2Ag^+(aq) ightleftharpoons Cu^{2 +}(aq)+2Ag(s)$; $K_c=\frac{[Cu^{2 +}]}{[Ag^+]^2}$ b. Balanced equation: $NH_3(aq)+H_2O(l) ightleftharpoons NH_4^+(aq)…
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01 question (4 points) how many atoms of titanium are there in 1.42 mol…
Part 1: $8.55124\times 10^{23}$ Part 2: $8.55124\times 10^{23}$ Part 3: $1.700248\times 10^{24}$ Part 4: $2.565372\times 10^{24}$
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what is the correct name for mgf₂? a. magnesium difluoride b. monomagne…
C. magnesium fluoride
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what is the name of the compound n₂o? a. nitrogen dioxide b. dinitrogen…
D. dinitrogen monoxide
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what is the formula for the compound sulfur hexachloride? a. s6cl b. sc…
B. $SCl_6$
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which of the following is a correct guideline when writing the iupac ch…
Binary ionic compounds are always named using the positive ion followed by the negative ion.
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what is the chemical formula for magnesium phosphide? a. mg2p3 b. mg3p2…
B. $Mg_3P_2$
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question 25 question a. if₇ b. p₂o₅ c. n₂o₅ which shows the correct nam…
A. Iodine heptafluoride, B. Diphosphorus pentoxide, C. Dinitrogen pentoxide
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a. if₇ b. p₂o₅ c. n₂o₅ which shows the correct names for these compound…
A. iodine heptafluoride B. diphosphorus pentaoxide C. dinitrogen pentoxide
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what does a chemical formula show? a. the number and type of each atom …
A. the number and type of each atom in a compound
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what is the suffix for all binary ionic compounds of representative ele…
B. -ide
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what is the chemical name for nacl? a. sodide chlorite b. sodite chlori…
D. sodium chloride
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in a chemical formula, which of the following indicates how many of eac…
B. subscript
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a student is modeling the units in the formula for aluminum sulfide usi…
The model that shows 2 aluminum ions ($Al^{3 + }$) and 3 sulfur ions ($S^{2 - }$) correctly represents the stable ionic compound for aluminum sulfide. Since no other models are sh…
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select the correct text in the passage. which detail best shapes the id…
At the entrance of a second person, hypocrisy begins. We parry and fend the approach of our fellow - man by compliments, by gossip, by amusements, by affairs. We cover up our thou…
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5. hydrogen is 99% ¹h, 0.8% ²h, and 0.2% ³h. calculate its average atom…
1. Average atomic mass of hydrogen: $1.012$ u 2. Average atomic mass of magnesium: $24.30$ u 3. Average atomic mass of iridium: $192.25$ u 4. The most abundant lithium isotope is …
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given the following mystery ions, $x^{3 +}$, $m^{2 -}$, $q^{2+}$, $j^{-…
Any formula that does not follow the charge - balancing rule for ionic compounds would be incorrect. Without specific incorrect formulas given as options, we can't choose a partic…
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calculate the average atomic masses. round all answers to two decimal p…
1. 178.55 2. 126.86 3. 197.50 4. 6.93
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based on the model shown, what is the formula for a compound containing…
C. $Li_2O$
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friendship by ralph waldo emerson (excerpt) there are two elements that…
B. Honesty and authenticity are the foundation for true friendships.
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which statement correctly explains how magnesium and chlorine combine t…
D. An Mg atom donates one electron to each of the two Cl atoms
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question icl4 ionic compound cs2s molecular compound k2s molecular comp…
B. $\text{ICl}_4$: Molecular Compound, $\text{Cs}_2\text{S}$: Ionic Compound, $\text{K}_2\text{S}$: Ionic Compound, $\text{MnO}_2$: Ionic Compound, $\text{N}_2\text{O}$: Molecular…
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the table lists the properties of various compounds composed of two dif…
1 - metal and nonmetal 2 - two nonmetals 3 - two nonmetals 4 - metal and nonmetal 5 - metal and nonmetal
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select two of the following compounds that are covalent. a. cacl₂ b. p₂…
B. $P_2O_5$
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4. lithium has only two stable isotopes. use the sim to determine the f…
a. 6.0151 amu b. 7.0160 amu c. 6.41546 amu d. It is closer to the mass of lithium - 6 because the difference between the average atomic mass (6.41546 amu) and the mass of lithium …
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2. calculate the atomic mass of each of the following elements using yo…
| Element | Calculated average atomic mass (amu) | | ---- | ---- | | Hydrogen | 1.007 | | Silicon | 28.18 | | Nitrogen | 14.00 | | Argon | 39.95 |
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experiment #2 based on the law of conservation of mass, predict the min…
Experiment #2: 24.3 g Experiment #3: 20.2 g
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2. beryllium (be) and fluorine (f) have only one stable isotope. use th…
The completed table is shown above.
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experiment #4 predict the mass of oxygen that will be left over after t…
1. 18.0 grams 2. 76 grams 3. 197 grams
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3. if 178.8 g of water is separated into hydrogen and oxygen gas, and t…
3. 158.8 g 4. 252.0 g 5. 8.2 g
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and isotopes review quiz which of the following statements are true reg…
Each atom has the same number of protons Each atom represents an isotope of 1 atom Each atom has a varying number of neutrons
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ions, and isotopes review quiz which of the following statements are tr…
This ion has a - 1 charge, This is an anion
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isotopes and atomic mass model 1: make isotopes open the isotopes and a…
1. Protons and neutrons. 2. Because it is the sum of whole - numbered protons and neutrons. 3. Carbon - 12; 12 amu. 4. 1 5. 1 6. Some elements with a single stable isotope may hav…
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question 4 (2 points) regarding ions, which of the following statements…
Atoms that gain electrons form ions with a negative charge. Atoms that lose electrons form ions with a positive charge.
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examine the data for each of the following reaction experiments and ans…
a. Mass of $Mg$ reactant: $48.6g$, Mass of $O_2$ reactant: $32.0g$ b. Mass of product: $80.6g$ c. Total mass of reactants: $80.6g$ d. Yes, the total mass of reactants ($48.6g + 32…
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ions, and isotopes review quiz which of the following statements are tr…
there are 4 protons there are 5 neutrons this atom has a mass number of 9
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ns, and isotopes review quiz 9 f fluorine 18.99 which of the following …
There are 9 protons in the nucleus, There are 9 electrons in a neutral atom
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ions, and isotopes review quiz. focusing on the two arrows, each is poi…
A. Proton B. Neutron
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3sio₂ silicon dioxide - glass and sand element si o how many atoms 3h₂s…
For $3SiO_2$: Si: 3, O: 6 For $3H_2SO_4$: H: 6, S: 3, O: 12 For $Fe_2O_3$: Fe: 2, O: 3
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niels bohr visual: timeline, later scientist, or modern application of …
- Bohr's atomic model inspired later quantum - mechanical models of the atom by scientists like Schrödinger. - His work is fundamental to modern chemistry as it helps explain chem…
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calculate how many atoms of each element are present in the following c…
| Compound | Element | Number of Atoms | |--|--|--| | $4CaCO_3$ | Ca | 4 | | $4CaCO_3$ | C | 4 | | $4CaCO_3$ | O | 12 | | $3H_2O_2$ | H | 6 | | $3H_2O_2$ | O | 6 | | $4FeS_2$ | Fe…
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3h₃po₄ phosphoric acid element h p o how many atoms 2h₂so₄ sulfuric aci…
| Compound | Element | Number of Atoms | |--|--|--| | $3H_3PO_4$ | $H$ | 9 | | $3H_3PO_4$ | $P$ | 3 | | $3H_3PO_4$ | $O$ | 12 | | $2H_2SO_4$ | $H$ | 4 | | $2H_2SO_4$ | $S$ | 2 | |…
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nahco₃ sodium bicarbonate - baking soda how many atoms 1 1 1 3 element …
| Element | C | H | O | | ---- | ---- | ---- | ---- | | How many atoms | 2 | 4 | 2 | | Element | Mg | O | H | | How many atoms | 1 | 2 | 2 |
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the simulation you just watched is called a build an atom because it is…
a. Fill outer electron shell via bonding. b. Atom gains or loses electrons. c. Change number of neutrons in nucleus.
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problem 4a: isotopes are atoms of the same element that have different …
Problem 4a: 1. Element name: Carbon 2. # of protons: 6 3. # of electrons: 6 4. # of neutrons: 6 5. Mass: 12 Problem 4b: 1. Element name: Carbon 2. # of protons: 6 3. # of electron…
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problem 4: isotopes are atoms of the same element that have different m…
1. Carbon 2. 6 3. 6 4. 6 5. 12
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problem 1: an ion has 5 protons, 5 neutrons, and 4 electrons. identify …
Boron ion ($B^{+}$), charge +1
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which element would most likely lose electrons to form positive ions wh…
Rubidium (Rb)
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problem 2: 1. create another example of an ion using the simulation 2. …
1. 11 2. 12 3. 10 4. Sodium ion 5. +1
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covalent and ionic bonding quick check which statement about sodium chl…
The sodium atom transfers electrons to the chlorine atoms to form ionic bonds.
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based on their locations in the periodic table, which two elements are …
Elements on the right side of the periodic table (non - metals) are most likely to form covalent bonds with each other. For example, carbon (C) and oxygen (O).
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problem 1: 1. create an example of an ion using the simulation 2. in th…
1. 11 2. 12 3. 10 4. Sodium ion 5. +1
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covalent and ionic bonding quick check which phrase best describes elec…
the relative strength with which an element attracts electrons in a chemical bond
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use the table to answer the question. elements with their electronegati…
bromine and nitrogen
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the sum of the protons and neutrons in an atom or isotope is called sel…
B. mass number
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when an atom gains 2 electrons, the resulting charge is select the best…
- 2 (corresponding to the option with value - 2)
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metals are almost always negative ions. select \true\ if each part of t…
False
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which of the following subatomic particles are responsible for the form…
C. electrons
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ionic bond covalent bond electrons type of materials (metals/nonmetals)…
| | Ionic Bond | Covalent Bond | |--|--|--| | Electrons | Transferred | Shared | | Type of materials (metals/nonmetals) | Metal and non - metal | Non - metals | | Melting point (h…
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6. can the same molecules be changed from one state of matter to anothe…
Yes. An example is water molecules which can be ice (solid), liquid water, or water vapor (gas).
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read shakespeares \sonnet 19\. devouring time, blunt thou the lions paw…
A. the abab, cdcd, efef, gg rhyme scheme C. the widespread use of iambic pentameter D. the use of three quatrains followed by a couplet