化学
化学反応、化学量論、分子構造、元素の性質。
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group 2 elements have two valence electrons. which kind of bond will th…
An ionic bond is likely because they will want to give away two valence electrons in order to become stable.
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11 multiple choice what factor determines the state of matter of a subs…
C. Temperature
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which group of elements has the most similar chemical properties? (1 po…
Fluorine, chlorine, and iodine
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which element would have a full outer shell of electrons if it gained t…
Nitrogen
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look at these details from a paragraph about the same topic: scientists…
Goggles are worn to protect people's eyes during different activities.
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where on the periodic table do you find elements that have full valence…
on the right side of the periodic table
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5. a student mixes two clear liquids. after a few minutes, yellow solid…
5. A. A solid (precipitate) formed., C. The mixture could not be separated by filtering 6. B. A new substance likely formed, showing signs of chemical change. 7. A. A color change…
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determination of a chemical formula data atomic mass: copper 63.546 cl …
Moles of copper: $0.0098$ moles Moles of water: $0.0081$ moles Mass of chlorine in sample: $0.164g$ Moles of chlorine: $0.0046$ moles Mole ratio, Chlorine : Copper in sample: $1:2…
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part 4 (2 points) aluminum combined with chlorine is... formula: aici₃ …
aluminum chloride
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example problems 1. a student mixes vinegar with baking powder, and bub…
1. B. A new substance formed because a gas was released 2. A. The sugar dissolves but remains the same substance; C. This is a physical change since the sugar could be recovered 3…
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on which atomic property proposed by henry moseley is the current perio…
atomic number
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select all the true statements. molecules of two different substances c…
Molecules of two different substances can be composed of the same chemical elements but have different numbers of atoms. Two different substances can be composed of different chem…
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which is true about stable isotopes? (1 point) isotopes that are natura…
A stable nucleus has a similar number of protons and neutrons.
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gallium has an atomic number of 31 and a mass number of 70. which table…
Protons: 31, Neutrons: 39, Electrons: 28
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to do or enact something, often immoral in nature; extremely religious;…
cease: to put an end to a state or an activity commit: to do or enact something, often immoral in nature expression: a particular look, action, or vocal intonation indicating some…
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part 3 (2 points) lithium combined with nitrogen is... formula: x x he …
lithium nitride
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which statement correctly compares the valence electrons for atoms of f…
Barium has more valence electrons, and they are in a higher energy level.
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which statement best explains why hydrogens atomic number is equal to i…
Hydrogen does not have any neutrons.
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1. a sealed jar contains liquid water. the jar is placed in a freezer u…
1. C. It stays the same because freezing is a physical change; D. It stays the same because the jar is sealed. 2. B. The total mass of the mixture is 215 g; C. The salt is still p…
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which element has four valence electrons? (1 point) o beryllium (be) o …
Silicon (Si)
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based on properties of elements in the periodic table, which element is…
vanadium (V)
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part 2 (2 points) calcium combined with hydrogen is... formula: x x he …
Formula: $CaH_2$ Name: calcium hydride
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based on properties of elements in the periodic table, which element is…
Copper (Cu)
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which statement about metals and nonmetals is correct? (1 point) most m…
Metals can be hammered into thin sheets, and nonmetals are brittle.
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1. use the ionic charges with your crisscross rule to get the correct c…
$Li_2S$, lithium sulfide $Na_3N$, sodium nitride $CaBr_2$, calcium bromide $AlP$, aluminum phosphide $LiCl$, lithium chloride $CaF_2$, calcium fluoride
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practice for each of the following, show compound formation (bonding) u…
| Pair of Elements | Lewis Dot Diagram (Electron - Transfer) | Chemical Formula | Name of Compound | | ---- | ---- | ---- | ---- | | Potassium and Fluorine | $K\cdot+\cdot\ddot{F}…
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look at these details from a paragraph about the same topic: touching a…
Coral reefs face various threats.
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use with textbook pages 128 to 135. writing names and formulas of ionic…
1. a) Silver oxide b) Potassium iodide c) Lithium chloride d) Barium oxide e) Zinc fluoride f) Magnesium phosphide g) Calcium bromide h) Sodium sulfide i) Aluminum chloride j) Ber…
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multiple choice question ozone is a highly reactive molecule of oxygen …
molecule of oxygen comprised of three atoms that absorbs ultraviolet radiation from the Sun
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covalent bonding basics manipulatives directions: for each set of atoms…
For hydrogen and chlorine: - Drawing of cards with circles showing electrons being shared: H:Cl (with 3 lone - pairs on Cl) - Lewis Structure:: H:Cl (single bond, 3 lone - pairs o…
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if the relative clause in bold is nonrestrictive, set it off with a com…
During his tour of the organic chocolate factory, Andrew learned about the Theobroma cacao which is a cacao tree native to the rain forests of Central America.
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read shakespeares sonnet 19. devouring time, blunt thou the lions paws,…
- the abab, cdcd, efef, gg rhyme scheme - the widespread use of iambic pentameter - the use of three quatrains followed by a couplet
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part 2 (1 point) label the most polar bond in ch₃oh by dragging the δ⁺ …
$\delta^+$ on H atom of O - H bond, $\delta^-$ on O atom of O - H bond.
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part 1 (1 point) see periodic table see hint label the most polar bond …
$\delta^+$ on C, $\delta^-$ on F
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a thought on the inestimable blessing of reason by mercy otis warren wh…
There are two stanzas with the rhyme scheme ABCB throughout.
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the most prevalent environmental threat to human populations caused by …
D. the contamination of surface and groundwater
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7 la concentration de sel dans leau de mer est de 35 g/l. dans leau dou…
$15,3\ L$
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2. for one of the following molecules/ions: i) draw the lewis structure…
i) Lewis structure: P is in the center with 5 single bonds to Cl atoms, and each Cl has 3 lone - pairs. ii) Electron - group arrangement: trigonal bipyramidal; Molecular shape: tr…
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question 17 a chemist combines water and acetic acid to make a mixture …
46 ### Question 18
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this group of elements can be dull or shiny and they partially conduct …
Metalloids
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which of the following is a physical property of elements? how shiny th…
All of the answers are physical properties of elements.
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which of the following is not a property of metals? they are shiny they…
They are poor conductors of heat and electricity
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which of the following statements is false regarding elements? they mak…
They can be broken down into simpler substances
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panyin wants to use this research for her informative essay. because or…
Research shows that organic foods pose less danger to human health than nonorganic foods.
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les fleurs de certaines variétés dhydrangeas changent de couleur selon …
a) Les anthocyanines, pigments acido - basiques, déterminent la couleur des hydrangeas en fonction du pH du sol. En sol acide, elles donnent la couleur bleue, en sol neutre ou bas…
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reactivity the ability of a substance to react with another substance i…
# Explicaciones Breves: 12. Según el texto, en la naturaleza, los elementos reactivos son los más probables de encontrarse como compuestos. 13. El texto indica que el hierro reacc…
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how are the atomic number and the number of protons related to each oth…
1. The atomic number is equal to the number of protons. 2. Mass number = Number of protons + Number of neutrons. 3. The number of protons determines the identity of an atom.
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decide whether each sentence below is punctuated correctly. use the dro…
1. Correct 2. Incorrect; revise to "I plan to go skiing with my sisters and with Charles and Boris." 3. Incorrect; revise to "Mariana hopes to study chemistry, geometry, and Itali…
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because of its chemical property of flammability, wood makes a good fue…
# Breve explicación: La madera no quemándose aún tiene la propiedad química intrínseca de ser inflamable. Un material no inflamable carece de esta propiedad química fundamental y …
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un contenant de 500 ml de solution concentrée de thé glacé renferme 150…
a) Prélève 18 ml de la solution concentrée de thé glacé et ajoute 282 ml d'eau pour obtenir 300 ml de thé glacé à 90 g/L de sucre. b) 1000 ml
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chemistry: ions and subatomic particles directions: complete the follow…
The completed table is shown above.
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which of the following best describes an element? 2/10 a mixture of dif…
A bunch of the same kind of atom
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what are chemical properties? a chemical property describes how a subst…
# Breve explicación: Según el texto, una sustancia puede cambiar en una nueva sustancia combinándose con otra sustancia o rompiéndose. # Respuesta: 1. Al combinarse con otra susta…
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chemistry: atomic number and mass number complete the following chart a…
The completed table is shown above. (Note: For cesium, the atomic number is 55 which was missing in the original table. For silver with mass number 107, number of neutrons is calc…
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un contenant de 500 ml de solution concentrée de thé glacé renferme 150…
1. Prélève $18\ ml$ de la solution concentrée de thé glacé. 2. Ajoute $282\ ml$ d'eau à la solution prélevée pour obtenir $300\ ml$ de thé glacé à $90\ g/L$ de sucre.
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properties of matter can be determined without changing composition, wh…
Physical; chemical properties of matter must change the composition of matter, while physical properties of matter can be determined without changing composition.
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pure substances are further divided into elements and compounds. which …
A compound.
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which of the following is not an example of a compound? hydrogen limest…
A. hydrogen
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un contenant de 500 ml de solution concentrée de thé glacé renferme 150…
a) Étape 1 : Prendre 18 ml de la solution concentrée de thé glacé. Étape 2 : Ajouter 282 ml d'eau. b) 1000 ml
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the ability of iron to react to oxygen is an example of - the combinati…
a chemical property.
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ocean water is a good example of a mixture because — o you can distingu…
the mixture of water and salt can be physically separated.
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calcule la concentration finale de chaque solution. a) on mélange 370 m…
La concentration finale est de $1,5\%$.
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7 véronique pèse 15,88 g de cuivre en poudre quelle fait ensuite chauff…
La masse a augmenté car le cuivre a réagi avec l'oxygène de l'air pour former du cuivre(II) oxyde. La masse d'oxygène ajoutée est de 4 g.
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6 en faisant longtemps chauffer 80,00 g de la substance x, murielle obt…
48,56 g
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calcule la concentration finale de chaque solution. a) on mélange 370 m…
$1,5\%$
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4. the pattern of stressed and unstressed syllables in a line of poetry…
4. Meter 5. Sonnet
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a) calcule le volume de chaque solution décrite ci - dessous. une solut…
a) Le volume est $0,6$ L. b) Le volume est $0,065$ L (ou $65$ mL).
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multiple choice question which is the primary factor in determining an …
its ratio of neutrons to protons
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6 calcule le volume de chaque solution décrite ci - dessous. a) une sol…
$0,6$ L
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which compound shows a correctly written formula between the atoms show…
D. AlCl₃
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which of these results from the particles of gases being farther apart …
A. Gases can be compressed more easily than liquids.
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21. which of the following is not an example of an arthropod? (a) crab …
21. C. sea urchin 22. A. ionic compound 23. C. the Earth rotates 360 degrees about its axis
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question 8 match the leavening agent to the correct category. - physica…
Physical - B. Air Biological - C. Yeast Chemical - A. Baking Powder
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bell-work 09/29/2025 how do you think gasoline helps power things like …
Gasoline contains chemical energy. Through combustion in engines or generators, it releases heat energy that is converted into mechanical energy to power these devices.
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most metals\tmost nonmetals good conductor\tpoor conductor high melting…
C. Most metals are malleable, and most nonmetals are not malleable.
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21. look at the graph. which solid is less soluble at higher temperatur…
21. d. cerium sulfate 22. a. sodium chloride
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4 calcule la masse de soluté contenu dans chaque solution décrite ci - …
a) 0,0525 g b) 156 g
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directed reading a continued 13. in a solution, the ____ is the substan…
13. solute; solvent 14. soluble 15. solvent 16. alloy 17. settle out or be filtered out 18. concentration 19. A dilute solution has a low amount of solute per unit volume of solve…
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5. which of the following is an example of a chemical process? (a) heli…
B. Iron forms rust.
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what is the missing particle? 82 35 br → ? + 0 -1 e 82 36 kr 82 35 kr 8…
$^{82}_{36}Kr$
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compare the boiling points of each pair. select the single best answer …
Part 1: $(CH_3)_3CCOCH_3$ Part 2: $(CH_3)_3CCH_2CHO$ Part 3: $(CH_3)_3CCH_2OH$
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4. how long does a hydrogen bond last? 5. how does the constant bonding…
4. Hydrogen bonds in water last on the order of picoseconds (10^-12 seconds). 5. The constant bonding and breaking of water molecules contribute to cohesion as there are always ma…
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section: mixtures 1. a pizza is a(n) properties of mixtures 2. a combin…
1. Mixture 2. Mixture 3. Compound 4. Its components can be physically separated and are not chemically bonded. 5. Physical 6. a. distillation 7. b. magnet 8. d. centrifuge 9. Firs…
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calcule la masse de soluté contenu dans chaque solution décrite ci - de…
$0,0525\ g$
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using the periodic table, predict the formulas of stable ionic compound…
C. Na₂O, sodium oxide D. BaS, barium sulfide E. MgCl₂, magnesium chloride
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the form of energy most responsible for producing sunlight is a heat en…
B. nuclear energy
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nuclear fission and fusion both affect the nucleus of an atom. choose a…
A. The final products of fission and fusion are elements that are different than the original C. Fission occurs mostly with elements heavier than lead on the periodic table
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which part of an atom participates in the reaction shown below? u235 + …
A. Nuclei
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select which type of bond is made for each chemical compound. nacl mgo …
- NaCl: Ionic - MgO: Ionic - CO₂: Covalent - KBr: Ionic - SiO₂: Covalent - CaCl₂: Ionic
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2. what shape does a water molecule have? draw what you think a water m…
A water molecule has a bent shape.
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magnesium is highly reactive and often forms an ion. select two element…
A. beryllium (Be), B. calcium (Ca)
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section 3: motion and forces continued not all objects fall to the eart…
1. The vector sum of all forces acting on an object. 2. Static friction prevents a stationary object from moving; sliding friction opposes the motion of a moving object. Static fr…
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match the element to the model that shows an isotope of that element. k…
Without seeing the exact number of protons in each model, we can't give a definite match. But the general approach is: For boron, look for a model with 5 protons; for carbon, 6 pr…
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fission and fusion are two types of reaction. a nuclear b chemical in t…
1. A. nuclear 2. B. energy 3. B. Helium
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using the data on the periodic table provided, which of the following s…
A. The number of valence electrons increase going from left to right because more electrons are added on the outermost energy level.
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which statement best differentiates physical hazards from chemical haza…
A. Physical hazards result from physical factors, such as noise or extreme temperatures, while chemical hazards result from exposure to harmful substances.
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which of the following is a property of a nonmetallic element? a. condu…
D. dull
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this diagram shows key components in a natural gas power plant. use an …
Chemical energy in natural gas → Heat energy from burning gas to make steam → Mechanical energy of turbine rotation → Electrical energy in generator → Electrical energy distributi…
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how many moles are in 223.2 g iron (fe)? a. 4 moles b. 55.8 moles c. 26…
A. 4 moles
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what are the units of molar mass? a. l/g b. g/mol c. g/l d. mol/g
B. g/mol