化學
化學反應、化學計量、分子結構與元素性質。
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multiple - choice question red has the ______________ wavelength. short…
B. Longest
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read the passage. night and her stars. ever the winds blow; ever the gr…
4. Man desires to find the interrelation of elements in nature.
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i. please write a physics - related sentence for each key term: one key…
A. $v\approx1.67m/s$ B. $d = 1500m$ C. $t = 100s$ D. $v = 2.5km/h$ E. $d = 1.6m$ F. $t = 384s$
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which two elements have the same number of energy levels with electrons…
B. boron and oxygen
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which phrase best describes a period on the periodic table? (1 point) o…
C. a row of elements
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which phrase describes a valence electron? (1 point) o an electron in t…
an electron in the outer energy level of an atom
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element groupings quick check based on its position in the periodic tab…
chlorine
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element groupings quick check which element has two valence electrons? …
calcium
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chemical reactions identify the reactants and products in the following…
|Equations|Reactants|Products|Balanced or Unbalanced Equation| |---|---|---|---| |$2H_2 + O_2 ightarrow2H_2O$|$2H_2$, $O_2$|$2H_2O$|Balanced| |$Na + O_2 ightarrow Na_2O$|$Na$, $O_…
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repaso de química general 1. define química y materia con tus propias p…
# Explicación: ## Paso 1: Definir química y materia La química es la ciencia que estudia la materia y sus transformaciones. La materia es cualquier cosa que ocupe espacio y tenga …
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what must differ between the atom of two different elements? o protons …
protons in the atom
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which components of the atom are found outside of the nucleus? neutrons…
electrons
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elements, molecules, compounds, mixtures classify each of the materials…
| Material | Pure Substance or Mixture | Element / Molecule / Compound Homogenous / Heterogenous | |--|--|--| | Sugar + Pure Water ($C_{12}H_{22}O_{11}+H_2O$) | Mixture | Homogeno…
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what is defined as anything made up of atoms that has mass and takes up…
D. matter
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the carbon in the oceans is present only in inorganic form as ions. tru…
FALSE
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which of the following does not contain significant amounts of carbon? …
c. Inorganic compounds
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which cycle is critical for the formation of organic compounds? a carbo…
A. carbon cycle
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write the systematic name of each organic molecule:
3,6 - dimethyloctane
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21. explain why table salt does not conduct electricity
Table salt in solid form does not conduct electricity because its ions are held in a fixed lattice by strong ionic bonds and there are no free - moving charged particles to carry …
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acetone is a common solvent that has a density of 0.7899 g/ml. what vol…
50.9
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solid / liquid / gas solids, liquids, and gases are phases of matter, d…
| | Molecule Diagram | Describe Movement | Shape (definite or indefinite) | Volume (definite or indefinite) | |--|--|--|--|--| | Solid | Molecules in a fixed - lattice pattern | V…
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solid / liquid / gas solids, liquids, and gases are phases of matter, d…
1. T 2. T 3. F 4. F
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6) choose which underlined part of the sentence is the correct independ…
6) Often, organic food products are marketed as the healthier and safer food choice. 7) There are skeptics who believe natural pesticides are just as harmful as man - made pestici…
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4) choose which underlined part of the sentence is the correct independ…
4) Researchers are studying organic foods 5) Organic foods are produced
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when a liquid turns into a gas at room temperature melting evaporation …
evaporation
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what is chemistry? the study of matter, its motion and behavior through…
The study of matter and its interactions
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select all the correct answers. which of these are examples of mixing a…
removing seed casings from grains, a soda bottle bubbling when it is opened, removing salt from seawater
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select the correct answer. the image shows the combustion of methane. w…
E. CH₄ + 2O₂ → CO₂ + 2H₂O
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select the correct answer. katrina inserts a key into her cars ignition…
B. activation energy
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select all the correct answers. which three statements are true about a…
B. They're harder than the pure metals they're made of, C. They're good conductors of electricity, E. They have a metal as their main component
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a pizza or chicken noodle soup is an example of a mixture. false true
True
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which characteristic of water contributes to its special, life - sustai…
The first option "Unequal sharing of electrons that creates polarity" and the third option "Presence of oxygen that causes bonds between molecules" contribute to water's special, …
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17. what is ice converted into during sublimation? a. hydrogen ions and…
D. water vapor
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which characteristic of water contributes to its special, life - sustai…
A. Unequal sharing of electrons that creates polarity
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use the figure below to answer question 15. 15. the figure shows the ar…
D. solid
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a very strong base might have a ph of
13
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which characteristic of water contributes to its special, life - sustai…
Presence of oxygen that causes bonds between molecules
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neutralization combustion synthesis decomposition replacement the react…
synthesis, decomposition, combustion, replacement, neutralization
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a polymer most closely resembles a link in a chain a chain an intersect…
B. A chain
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select the correct answer. in a given chemical reaction, the energy of …
A. Energy is absorbed in the reaction.
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in a chemical change, a chemical reaction occurs and new products form.…
1. Physical change 2. Chemical change 3. Physical change 4. Chemical change 5. Chemical change 6. Chemical change 7. Physical change 8. Chemical change 9. Physical change 10. Chem…
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drag each tile to the correct location. classify the chemical equations…
Balanced: 2CO + 2NO → 2CO₂ + N₂, H₂CO₃ → H₂O + CO₂ Not Balanced: 6CO₂ + 6H₂O → C₆H₁₂O₆ + O₂, 2Cu + O₂ → CuO
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using punctuation deciding when to use semicolons in lists which senten…
My three sisters live in Gary, Indiana, Bloomington, Indiana, and Portland, Oregon.
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ii. what is the atomic number of this atom? a. 3 b. 4 c. 5 d. 6
A. 3
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select the correct answer. which law represents a balanced chemical equ…
C. law of conservation of mass
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select all the correct answers. which of these processes are chemical r…
boiling an egg, vegetables rotting
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drag the tiles to the correct boxes to complete the pairs. identify the…
Michael uses a car that burns fossil fuels. - combustion reaction Alan grows tomatoes on his farm. - photosynthesis Lisa eats eggs for breakfast. - respiration
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question 24 household cleaners that contain bleach and those that conta…
# Explicaciones Breves: Para la pregunta 24, en una reacción de doble reemplazo, los iones de dos compuestos intercambian posiciones. En $NaOCl + NH_3 ightarrow NaOH + NH_2Cl$, el…
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12. a 12.00 - liter box had 4.50 moles of chlorine gas. if 2.00 moles o…
$17.33$ L
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question 21 which of the following shows the reaction correctly balance…
Pregunta 21: $2Ag + Cl_2 ightarrow2AgCl$ Pregunta 22: Síntesis Pregunta 23: Box K
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which sentence contains a dependent clause? a. tonights winner will rec…
D. Until we get to Brooklyn, we're not allowed to sleep.
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4. what type of reaction is shown in the graph? how do you know? reacta…
The reaction is an exothermic reaction. We know this because the energy of the reactants is higher than the energy of the products, and energy is given out to the surroundings.
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question 18 a jeweler tells you that your ring has 0.15 moles of gold i…
Pregunta 18: 29.6 g Pregunta 19: $2AlCl_3 + 3Na_2CO_3 ightarrow Al_2(CO_3)_3+6NaCl$ Pregunta 20: $2Al(OH)_3 ightarrow Al_2O_3 + 3H_2O$
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which of the following is a carboxyl group? -oh -nh2 -c-o -cooh
-COOH
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part a a hydroxyl group is also called a carbonyl group. characteristic…
D. characteristic of alcohols
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which statement about hydrocarbons is false? hydrocarbons can form stra…
C. Hydrocarbons are inorganic compounds
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11. if a gas in an expandable container is pressurized from 15.0 atmosp…
$1.65$ mol
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question 15 which of the following shows the reaction correctly balance…
# Explicación detallada: ## Paso 1: Balancear la ecuación de la reacción de hierro con cloro La reacción química entre hierro ($Fe$) y cloro ($Cl_2$) produce cloruro de hierro. El…
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part a organic compounds always contain nitrogen always contain carbon …
always contain carbon
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part 2 (1 point) select the atoms in histrionicotoxin 283a that are sp²…
Carbon atoms in the double - bonded (alkene) regions of the histrionicotoxin 283A structure.
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the reaction below is not balanced. 4fes + 8o₂ → 2fe₂o₃ + 8so₂. which o…
Pregunta 12: The iron atoms are not balanced. Pregunta 13: 18 g/mole Pregunta 14: 2.41 g
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a cube of an unknown metal has a volume of 2.25 cm³ and a mass of 16.2 …
Chromium
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3. atoms of an element that differ by their mass numbers are called ___…
isotopes
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question 9 what is the volume of an object with a density of 2.25 g/cm³…
### Explicación paso a paso: #### Paso 1: Calcular el volumen en la pregunta 9 La densidad ($d$) está dada por la fórmula $d=\frac{m}{V}$, donde $m$ es la masa y $V$ es el volumen…
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the study guide. 1. the electrically neutral particles in the nucleus o…
neutrons
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question 6 the balanced chemical equation for the combustion of propane…
Question 6: $C_3H_8 + 5O_2 ightarrow3CO_2 + 4H_2O$ Question 7: 50160 J Question 8: $M_2Nm_3$
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1. which would most likely cause an increase in the energy of water mol…
1. b. boiling the water 2. a. Sodium chloride is the solute, water is the solvent, and salt water is the solution. 3. d. a heterogeneous mixture 4. b. Does the substance contain m…
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question 4 1 pts based upon molecular structure, which of the following…
framework silicates
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what is the significance of carbon having four valence electrons? valen…
The outermost shell can form up to four covalent bonds.
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which of the following best describes why the reaction is not balanced?…
The oxygen atoms are not balanced.
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identify each transition in this flowchart as a chemical change or a ph…
From top - down, left - to - right: chemical, physical, physical, chemical
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identify each transition in this flowchart as a chemical change or a ph…
The transitions labeled "chemical" are chemical changes as they involve the formation of new substances at the molecular level. The transitions labeled "physical" are physical cha…
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question 3 what is the mass of an object with a density of 2.50 g/cm³ a…
### Pregunta 3 # Explicación: ## Paso 1: Convertir volumen a cm³ Sabemos que 1 mL = 1 cm³, entonces 17.50 mL = 17.50 cm³. ## Paso 2: Usar la fórmula de densidad La densidad $ ho=\…
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question select all the correct answers. which two facts about plastic …
B. Some plastics release toxic chemicals., D. They don't break down over time.
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question 1 air bags must inflate within a fraction of a second in order…
Pregunta 1: Decomposition Pregunta 2: 18 g/mL
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15. what determines the strength of london dispersion forces? a. the at…
C. The size and shape of the molecule
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14. which molecule is an example of a non - polar molecule? a. hydrogen…
B. Methane ($CH_4$)
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12. which factor contributes to the higher boiling point of ethanol (c₂…
C. Hydrogen bonding in ethanol
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3. which of the following substances is likely to be a gas at room temp…
A. Methane ($CH_4$)
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question 7 of 10 which of these uses ethos? a. the food at our school i…
B. Yum Organics has been providing well - rounded organic lunches to schools on the West Coast for more than 15 years.
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multiple choice question echo charts can be used to study the propertie…
C. different rocks and sediments reflect signals differently
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functional groups confer specific chemical properties to the molecules …
- Alcohol: is polar and makes compounds more soluble in water (the molecule with -OH group) - Carboxylic acid: acts as an acid (the molecule with -COOH group) - Aldehyde: may be a…
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part a identify an ether. ch3ch2sch2ch3 ch3ch2ph2 ch3ch2och2ch3 ch3ch2s…
$CH_3CH_2OCH_2CH_3$
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which of the following elements could be e? a. s b. f c. p d. i e. o
c. P
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part a upon combustion, a 0.8009 g sample of a compound containing only…
$C_2H_4O$
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part b enter the formula for phosphorus tribromide. express your answer…
$PBr_3$
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part c (3 of 3) - classifying molecules by their functional groups 3 tr…
Alcohol: Molecule with -OH group, is polar and makes compounds more soluble in water Carboxylic acid: Molecule with -COOH group, acts as an acid Aldehyde: No molecule shown Thiol:…
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using the rules for naming molecular compounds described in the introdu…
Carbon tetrachloride Dinitrogen tetrahydride
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part a what is the name of the covalent compound ccl₄? enter the full n…
Part A: Carbon tetrachloride Part B: Dinitrogen pentoxide
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functional groups confer specific chemical properties to the molecules …
| Functional Group | Chemical Property | | ---- | ---- | | alcohol | None of the given properties are a perfect match<br> | | carboxylic acid | acts as an acid | | aldehyde | None…
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name the compound hc₂h₃o₂(aq). hydroacetous acid acetic acid hydroaceti…
B. acetic acid
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pre - test page 6 of 9 31. what does a credit bureau do? a. extends cre…
31. c. tracks the bill - paying habits of consumers 32. a. lower and the interest paid is higher. 33. c. the higher the risk of nonpayment, the higher the interest rate 34. b. ann…
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rbi spell out the full name of the compound. view available hint(s) rub…
barium bromide
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sno spell out the full name of the compound. view available hint(s) sub…
Part A: Tin(II) oxide Part B: Chromium(III) sulfide Part C: Rubidium iodide
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crcl3 spell out the full name of the compound. part e hgbr2 spell out t…
Part A: Chromium(III) chloride Part E: Mercury(II) bromide Part F: Chromium(III) chloride
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sno₂ spell out the full name of the compound. part b hgbr₂ spell out th…
Part A: tin(IV) oxide Part B: mercury(II) bromide Part C: cobalt(II) chloride
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magnesium and sulfur express your answer as a chemical formula. a chemi…
Part C: MgS Part D: $BaBr_{2}$
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name the compound first as if it were ionic compound - no prefixes - ca…
HBr(aq): hydrobromic acid H₂CO₃(aq): carbonic acid H₂SO₃(aq): sulfurous acid hydrofluoric acid: hydrogen fluoride sulfuric acid: hydrogen sulfate nitrous acid: hydrogen nitrite HI…
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the data in the table concern the lactonization of hydroxyvaleric acid …
(a) $-0.0069$ (b) $-0.0081$ (c) $-0.0115$
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the molecule shown here contains four functional groups. choose the opt…
(Without seeing the highlighted atoms clearly in the options, it's impossible to give a specific correct option. But the general approach is to check each option for correct highl…