化学
化学反応、化学量論、分子構造、元素の性質。
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which of the following is false? two objects, both having positive char…
Electrostatic forces are responsible for the energy absorbed or released in chemical changes.
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1 the atom shown in the diagram has four energy levels or shells false …
1. False 2. False 3. False 4. True 5. True 6. False 7. True 8. True 9. True 10. False
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classify each of the following pure substances as either an element or …
Nickel: Element Copper: Element Silicon dioxide: Compound
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2. find the mass of a sample of mercury (d = 13.5 g/ml) if the volume i…
134301 g
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classify each of the following particulate level illustrations as a rep…
Top image: Compound Middle image: Element Bottom image: Compound
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a mixture of sand and isopropyl alcohol could most easily be separated …
filtration
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indicate whether each statement about atomic energy levels is true or f…
1. False 2. False 3. False 4. True 5. True 6. False
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classify each of the following mixtures as either homogeneous or hetero…
Apple juice: Homogeneous Pure air: Homogeneous Concrete: Heterogeneous
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question 10 of 10 which kind of force is a dipole - dipole force? a. in…
A. Intermolecular attraction
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classify each of the following particulate level illustrations as a rep…
Top image: Mixture Middle image: Mixture Bottom image: Pure substance
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question 9 of 10 which of the following is a result of intermolecular f…
B. Hydrogen bonds
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question 8 of 10 what does a nonpolar covalent bond show about the elec…
B. The difference in electronegativities of the two atoms is very small.
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in the illustration, o is color - coded as red. is the change represent…
Physical change
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question 7 of 10 how does molecular shape affect polarity? a. if the mo…
B. If the molecule is symmetrical, the effects of polarity will cancel out.
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question 6 of 10 which of these molecules is nonpolar? a. o₂ b. co c. c…
A. $O_2$
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classify each of the following changes as chemical or physical: rusting…
Rusting of iron: Chemical Souring of milk: Chemical Stretching a rubber band: Physical
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sprinters set in the starting blocks at the beginning of a race rely on…
D. Chemical potential energy converting to kinetic energy
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question 5 of 10 which kind of covalent bond has unequal sharing of ele…
D. A polar covalent bond
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classify each of the following properties as chemical or physical: acid…
Acidity: Chemical Combustibility: Chemical Viscosity: Physical
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question 4 of 10 what kind of force acts within a molecule? a. an inter…
B. An intramolecular force
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question 3 of 10 which of the following molecules contains a nonpolar c…
B. $H_2O$, C. $HCl$
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in the following descriptions the particles are atoms, molecules, or io…
Helium: The sample fills its container. Milk: Neither of the given descriptions. Sugar: The particles vibrate about fixed positions.
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question 2 of 10 which of the following is an important application of …
A. Holding DNA together
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why are van der waals forces important? a. they determine how strong di…
D. They are the primary intermolecular attractive forces that act between nonpolar molecules.
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the following illustrations represent different states of the substance…
Top: Solid; Middle: Liquid; Bottom: Gas
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the atomic number of an atom is multiple choice the number of protons i…
the number of protons in the atom.
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what kind of bond is the result of the transfer of an electron? a. a hy…
C. An ionic bond
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question 9 of 10 why do atoms tend to be bonded to other atoms? a. atom…
D. Atoms form bonds to make the results more stable
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what kind of bond is present in nabr? a. covalent bond b. hydrogen bond…
C. Ionic bond
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question 7 of 10 which statement is the best description of a chemical …
D. A chemical bond holds atoms together.
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which of the following examples is a molecule with a covalent bond? (us…
D. CO
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question 5 of 10 which of the following diagrams is the correct electro…
B. $\cdot\ce{Al}\cdot$
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how many total valence electrons take part in a triple bond between 2 a…
D. 6
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what is a covalent bond? a. a bond between two atoms resulting from a t…
D. A bond between two atoms that is made up of shared electrons
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which of the following values best classifies a bond between 2 atoms as…
B. An electronegativity difference of greater than 1.7 between the atoms
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what kind of bond would two nonmetals typically make? a. an ionic solid…
B. A covalent bond
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substance #2 mass: 7.39 g volume of water: 30.5 ml volume of water and …
The density of substance #2 is approximately $0.754\ g/ml$
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question 10 of 10 which of the following elements is the largest? a. ca…
D. Boron (B)
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question 9 of 10 what makes the atomic radius change along a period in …
B. More protons in the nucleus pull the electrons in, making the atomic radius smaller.
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question 8 of 10 what does the electronegativity of an atom indicate? a…
A. The tendency of the atom to pull on electrons
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question 7 of 10 why do metals tend to lose electrons to form positive …
D. A metal atom loses its few valence electrons to form a full octet.
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question 6 of 10 what trend does the atomic radius follow along a perio…
C. The atomic radius gets smaller the farther right it appears on the periodic table.
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3. in what ways does the play address issues of race and identity? 4. w…
3. Analyze play's race - identity aspects. 4. Character revealing loyalty and reason. Section 4:1. Handkerchief's significance and Iago's use.
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question 5 of 10 what trend does the first ionization energy follow, go…
A. The first ionization energy decreases because the outermost electron is farther from the nucleus.
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question 2 of 10 what does the law of conservation of matter show? a. t…
B. That the total number of atoms in matter will never change.
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complete the sentences using the words provided. 1. a(n) (click to sele…
1. acid 2. base 3. buffer 4. increases 5. hydroxide (OH⁻) 6. negative logarithm 7. decreases
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question 4 of 10 which of the following elements shows little reactivit…
B. Argon (Ar)
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question 3 of 10 which of the following elements has the largest first …
D. Nitrogen (N)
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match each label with the correct location on the diagram. labels drop …
Hydrogen bond: The dashed - line between the hydrogen and oxygen atoms. Hydrogen atom: The small white spheres. An organic molecule: The larger molecule with multiple carbon - con…
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question 2 of 10 which of the following elements has the highest electr…
A. Nitrogen (N)
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what does a periodic trend look like on the periodic table? a. a set of…
D. A repeating pattern
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question 10 of 10 how many different sublevels are in the first energy …
C. 1
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which of the following phrases describes core electrons? a. electrons t…
C. Electrons that are closest to the nucleus
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how many different d orbitals are within the 3d sublevel? a. 3 b. 7 c. …
C. 5
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match each label with the correct location on the diagram. labels drop …
Hydrogen bond: The dotted - line between the partially charged atoms. Hydrogen atom: The small white spheres attached to carbon and oxygen. An organic molecule: The chain of grey …
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which is the only kind of orbital in the first energy level? a. an f or…
C. An s orbital
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how many total orbitals are within the 3s, 3p, and 3d sublevels of the …
C. 9
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which of the following phrases describes how the position of an electro…
A. The farther an electron is from the nucleus, the greater its energy.
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what does the period number tell about the energy levels occupied by el…
D. The period number tells which is the highest energy level occupied by the electrons.
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question 3 of 10 which of the following elements has 3 electrons in the…
B. N
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the fat molecule shown above containing three long tails are fatty acid…
London dispersion forces
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question 2 of 10 which of the following notations is the correct noble …
A. [Ar]4s²3d⁷
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what is the correct electron configuration of phosphorus (p)? a. 1s²2s²…
D. $1s^{2}2s^{2}2p^{6}3s^{2}3p^{3}$
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for each statement below, indicate whether it is true or false. 1. brea…
1. False 2. False 3. True 4. True 5. True 6. False 7. False 8. True 9. False 10. True
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2. find the mass of a sample of mercury (d = 13.5 g/ml) if the volume i…
134301.12 g
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indicate whether each statement about the reactivity of elements is tru…
1. True 2. False 3. True 4. True 5. False 6. False 7. False
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the relatively weak ________ bonding between neighboring water molecule…
C. hydrogen
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question 10 of 32 how many protons are in chlorine (cl)? the periodic t…
B. 17
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question 9 of 32 how many electrons are in an ion of calcium (ca2+)? th…
A. 18
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question 8 of 32 what is the atomic mass of magnesium (mg)? the periodi…
A. 24.3
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question 36 of 36 which of the following is the energy of motion? a. ch…
A. Chemical potential energy
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this law was proposed by joseph proust and is known as the law of const…
1. D. law of definite proportions 2. B. proton
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choose the appropriate atomic number, mass, or property for each descri…
1. 4 2. 1 3. 7 4. 12 5. 27 6. 13 7. 30 8. 10
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question 6 of 32 which is the main type of element found in the upper r…
A. Nonmetals
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chemical reactions for each chemical reaction indicate whether the firs…
1. $NaOH ightarrow Na^+ + OH^-$: Base 2. $HCl ightarrow H^+ + Cl^-$: Acid 3. $NH_3 + H_2O ightarrow NH_4^+ + OH^-$: Base 4. $H_2CO_3 ightarrow H^+ + HCO_3^-$: Acid
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question 20 of 25 what was the atomic theory about? a. the existence of…
D. The structure of the atom
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question 5 of 32 which element has 6 valence electrons? the periodic ta…
A. Selenium (Se)
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question 19 of 25 an atom of aluminum (al) has an atomic number of 13 a…
D. 14
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question 18 of 25 why do elements within a period of the periodic table…
B. They have different numbers of valence electrons.
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question 16 of 25 what are the alkali metals? a. group 18 on the period…
C. The first group on the periodic table
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question 16 of 25 what are the alkali metals? a. group 18 on the period…
C. The first group on the periodic table
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question 15 of 25 which characteristic gives the most information about…
C. The atomic number
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the subatomic particle without an electric charge is called a(n) ____. …
1. A. neutron 2. No correct option provided (should be law of constant composition which is not listed as an option here)
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question 14 of 25 which element contains the same number of valence ele…
D. Si
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question 13 of 25 how are the elements arranged in the current periodic…
D. In order of increasing atomic number
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question 3 of 32 which type of element is almost always found as a sing…
C. Noble gas
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question 11 of 25 what is the symbol for potassium? a. p b. k c. pt d. …
B. K
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11. drag and drop the scientists with the statements. choices: crookes,…
1. Aristotle 2. Democritus, Leucippus 3. Aristotle 4. Dalton 5. Crookes 6. Rutherford 7. Thomson
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question 10 of 25 which family contains liquids, solids, and gases? a. …
B. The halogens
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question 9 of 25 what is another name for group 8a? a. group 18 b. grou…
A. Group 18
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question 2 of 32 what type of energy is stored in batteries? a. electri…
C. Chemical energy
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the condensation of water droplets on a glass of iced tea is an example…
C. phase change
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hands moving on a battery - operated clock is an example of what kind o…
B. Chemical potential energy being converted to kinetic energy
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question 1 of 32 which is a property of potassium (k)? a. it is not rea…
C. It is extremely reactive.
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the relatively weak ________ bonding between neighboring water molecule…
C. hydrogen
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question 4 of 25 thermal windows often have all the air pumped out betw…
A. Ar
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which subatomic particles interact in the chemical bonding between atom…
D. electrons
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question 2 of 25 which element is in the alkali - metal family? a. calc…
D. Lithium (Li)
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select the correct description of elements. all of these are correct. p…
particles that cannot be broken down into other substances
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8. choose all that apply. which five postulates were proposed by dalton…
- All matter is composed of extremely tiny particles called atoms. - Atoms cannot be created or destroyed (law of conservation of mass) nor can they be divided into smaller partic…