化学
化学反応、化学量論、分子構造、元素の性質。
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the chemistry of a cold pack is described by the following equation: nh…
q is positive
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hydrogen peroxide (h₂o₂) is decomposed in a beaker to form oxygen (o₂) …
q = negative and the reaction is exothermic
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hydrogen gas is burned in the presence of oxygen, in a cylinder that ha…
q is negative and the overall process is exothermic.
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one form of hand warmer consists of finely divided iron powder, that wh…
This reaction is exothermic and has negative \(q\)
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nucleosynthesis in stars (due midnight 10/27) • elements created during…
Fe, Iron
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nucleosynthesis in stars (due midnight 10/27) • elements created during…
Heavier and Heavier
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multiple choice question chemical digestion of ______ begins in the sto…
nucleic acids and proteins
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multiple choice question ingested nutrients spend at least hours in the…
4
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which statement describes what happens when ice freezes, according to t…
- First question: The water molecules decrease their speed. - Second question: gas
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which word best describes a substance where its atoms and molecules are…
- First question: hot - Second question: temperature
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use the slides (link in the instructions) to complete these questions. …
Heat is due to the motion of molecules.
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hydrogen fuel cells are a promising source of energy. which of these is…
water
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biomass energy can be a sustainable carbon - neutral source of energy. …
We burn it (combustion) or chemically convert it to biofuel.
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(02.04 mc) if you want to make a strong battery, should you pair two me…
A mix. One metal (low electron affinity) donates electrons (oxidation at anode), another (high electron affinity) accepts electrons (reduction at cathode), enabling electron flow …
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name 5 places where carbon is found.
Atmosphere, living organisms, fossil fuels, limestone (rocks), ocean.
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if an ion gains an electron, what happens to its oxidation state?
The oxidation state of the ion decreases.
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spontaneous reactions that release energy are called ______________.
exothermic reactions
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fill in the blank question the function of the digestive system that in…
absorption
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4. carbon dioxide (co₂) is carbon hooked up with what other element? b.…
B. Oxygen
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2021 ap chemistry free-response questions 3. a student is given the tas…
\(Ba^{2+}(aq)+SO_4^{2 -}(aq)=BaSO_4(s)\) ### (b)
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what historical scientists were crucial in understanding waters molecul…
1. Lavoisier and Cavendish 2. 7 3. Through partial positive and negative charge attractions
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how does the presence of solutes affect the freezing point of a solutio…
It lowers the freezing point.
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what is a nonelectrolyte? a substance that forms a large number of ions…
A substance that does not conduct an electric current when dissolved in solution.
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the student designs the following procedure to produce a calibration cu…
The student most likely executed Step 3 incorrectly. If the cuvette was not rinsed thoroughly with the standard solution (e.g., there was residual water or a less - concentrated s…
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read this excerpt from a passage. \one of the most common organic desig…
extended definition
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which of the following is an example of a weak electrolyte? * sugar (c₁…
Ammonia (\(NH_{3}\))
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why is acetic acid considered a weak electrolyte? it forms a strong ion…
It ionizes less readily than hydrochloric acid.
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fill in the blank question the pressure exerted by each gas within a mi…
partial pressure
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what is the boiling point of pure water at sea level?
100°C
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why does water have a bent, v - shaped molecular structure? * 2 points …
- First question: Electron repulsion between negatively charged electrons - Second question: Uneven electron distribution creating partial charges - Third question: By attracting …
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what is the process called when a solid is dissolved in a liquid to for…
Dissolution
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what is osmotic pressure dependent on? volume of the solution type of s…
Concentration of solute particles, Temperature of the solution.
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read the following sentences: lydias gambit to find the secret ingredie…
scheme
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what is the term used to describe the temperature at which a liquid tur…
Freezing point
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what is the role of a water molecule in forming a hydronium ion? it for…
It forms a covalent bond with $H^+$.
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what happens when you mix a highly solid solution with water? it dissol…
It dissolves completely
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read the sentence below. if you have any difficulty reaching the custom…
C. Problem - solution
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read the sentence below both sport utility vehicles and sedans emit the…
D. Compare and contrast
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which phrase defines altitude? how tightly molecules are packed a colum…
the height of a given point above sea level
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ap chemistry free response practice unit 2 name: 2022 ap chemistry free…
\(525\space nm\) (approximate value from the peak of the absorbance - wavelength graph) # (b)(i)
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you have been asked to write an essay about the effects of large amount…
The first option (the one with the thesis statement: "Sugar is in everything these days. You have to be careful and look at labels to make sure that you are not going over your da…
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multiple choice question if you wanted to research the benefits of addi…
What are benefits of fluoridating tap water?
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iala is conducting an experiment in her chemistry class. she needs to c…
\(4Al + 3O_2 ightarrow 2Al_2O_3\)
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michael is conducting an experiment where he mixes substance a (5g) wit…
\(4\) grams.
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aria is learning about chemistry in school. she reads that water is mad…
A group of atoms bonded together is called a molecule.
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what is the mass of chlorine used during the reaction? chlorine + potas…
\(16.63\space g\)
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scarlett is conducting an experiment where she mixes 5g of substance a …
\(4g\)
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what state of matter is the sample? solid gas liquid
solid
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emma is making ice cubes in her freezer. she notices that the process o…
release energy
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james is looking at a chemical formula and notices a number written to …
Subscript
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lily is working in a chemistry lab and is trying to extract iron from i…
balanced
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james is baking a cake. he notices that after mixing all the ingredient…
Transformed, changed
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sophia is doing a science experiment and uses a compound with the chemi…
6 oxygen atoms
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which of these is an example of a physical property? chlorofluorocarbon…
Chlorine gas is yellow - green in color.
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emma is making ice cubes in her freezer. she notices that the process o…
release energy
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suppose a reaction were to happen in an open container in a lab. during…
The gas that was produced was not able to be weighed since the container was open.
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evelyn mixes vinegar and baking soda in a sealed container. after the r…
Mass is never created or destroyed.
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evelyn mixes vinegar and baking soda in a sealed container. after the r…
Mass is never created or destroyed.
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which of the following would provide the evidence that the number of at…
The mass of the plastic bag, baking soda, and vinegar before the reaction was equal to the mass after the reaction.
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ionic bonding practice follow all directions for credit > draw the lewi…
For Mg and I: $[\text{Mg}]^{2 + }[\cdot\!\ddot{I}\cdot]^{-}[\cdot\!\ddot{I}\cdot]^{-}$ For Al and Cl: $[\text{Al}]^{3 + }[\cdot\!\ddot{Cl}\cdot]^{-}[\cdot\!\ddot{Cl}\cdot]^{-}[\cd…
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daniel is conducting an experiment in his chemistry class. he needs to …
\(4Al + 3O_2\to2Al_2O_3\)
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are synthesis reactions get cold release energy have higher energy in t…
release energy
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10 g of a solid chemical reacts with a 10 g of a liquid chemical, the r…
The gas produced weighed \(7\ g\)
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in harpers chemistry class, she is balancing a chemical equation on the…
Coefficient
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anika mixes 10 grams of sugar with 90 grams of water in a closed contai…
The total mass in the container is \(100\space g\) because according to the law of conservation of mass, in a closed system, the mass of the reactants (sugar + water) equals the m…
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the calibration is to 1 ml, so we estimate another digit. what is the v…
\(67.4\) mL
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read the following scenario and answer the question that follows. when …
C. conditioning
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1.2 the metric system name: directions: answer the following. convert t…
## Convert the following: 1. \(0.25\space L\) 2. \(25.6\space kJ\) 3. \(5\space mg\) 4. \(1200\space mL\) 5. \(0.375\space g\) 6. \(1380\space J\) 7. \(500\space mL\) 8. \(0.125\s…
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how does rb bond with other elements? (1 point) rb loses an electron. r…
Rb loses an electron.
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which of the following combination of elements is the most reactive? (1…
Cs and Br
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patterns of reactivity quick check which feature is unique to group 18 …
They are very nonreactive.
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how do nonmetals tend to form bonds? (1 point) by gaining electrons by …
by gaining electrons
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patterns of reactivity quick check why does the reactivity of metals in…
Metals on the right have more protons, causing valence electrons to be held more strongly.
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a set of frequencies of the electromagnetic waves emitted by atoms of t…
Atomic emission spectrum
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when atoms absorb energy they become _________. ○ crystals ○ compounds …
C. excited
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complete the table; the first two rows have been done for you. use your…
| Element | Symbol | Protons | Neutrons | Electrons | | ---- | ---- | ---- | ---- | ---- | | Lithium | Li | 3 | 4 | 3 | | Carbon | C | 6 | 6 | 6 | | Sodium | Na | 11 | 12 | 11 | |…
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g) iron + oxygen → iron oxide skeleton equation chemical equation type …
- g) - Skeleton equation: \(Fe+O_2 ightarrow Fe_2O_3\) - Chemical equation: \(4Fe + 3O_2=2Fe_2O_3\) - Type of reaction: Combination reaction - h) - Skeleton equation: \(K + Br_2 i…
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5. besides chemical weapons, what other new weapon helped to end the st…
D. Tanks
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elige una respuesta y pulsa \siguiente\. recibirás tu puntuación y resp…
Los elementos constan de un solo tipo de átomo.
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complete este cuestionario para finalizar la tarea de química moderna q…
Todas son correctas.
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balancing equations worksheet 1. for each of the following write the co…
a) - Skeleton equation: \(CuO + H_2 ightarrow Cu + H_2O\) - Chemical equation: \(CuO + H_2 = Cu + H_2O\) - Type of reaction: Single - displacement reaction b) - Skeleton equation:…
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complete este cuestionario para finalizar la tarea de química moderna q…
Un cambio en la cantidad de energía
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complete este cuestionario para finalizar la tarea de química moderna q…
Toda materia existe en al menos una fase
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complete este cuestionario para finalizar la tarea de química moderna q…
Todas las afirmaciones son correctas, por lo que la respuesta es "Todos son correctos".
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complete este cuestionario para finalizar la tarea de química moderna q…
Un cambio en la cantidad de energía
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complete este cuestionario para finalizar la tarea de química moderna q…
Toda materia existe en al menos una fase
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question 1 the sticking together that occurs between particles of diffe…
B. adhesion
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3.1.9-12.f the results of the experiment most strongly support which co…
Lipid molecules are nonpolar(hydrophobic) because they repel water molecules, which are polar.
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identifying reactions use table 1 to identify the reactions below. then…
1. Synthesis, \(4Fe + 3O_2=2Fe_2O_3\) 2. Double - displacement, \(FeS+2HCl = FeCl_2+H_2S\) 3. Single - displacement, \(Cl_2+2NaBr=2NaCl + Br_2\) 4. Combustion, \(C_{10}H_8+12O_2=1…
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how will you know if the equation is balanced? because if i switch the …
The balanced equation is \(N_2+3H_2 ightarrow2NH_3\)
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4. what are three properties of covalent compounds? 5. why do we not si…
4. Low melting/boiling points, poor electrical conductivity, often gases/liquids at room temp. 5. Formula represents actual molecular atom count. 6. Lone pairs. 7. Ionic compound.…
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complete este cuestionario para finalizar la tarea de química moderna q…
Toda materia existe en al menos una fase
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complete este cuestionario para finalizar la tarea de química moderna q…
Nuclear
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complete este cuestionario para finalizar la tarea de química moderna q…
Todas las afirmaciones son correctas, por lo que la respuesta es "Todos son correctos".
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multiple - choice question buffers make our bodies more basic prevent c…
prevent changes in pH of our bodies
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¿cuál de las siguientes afirmaciones es verdadera? informar un err preg…
Los gases tienen la mayor energía; por lo tanto, tienen la mayor cantidad de espacio y los enlaces más débiles entre sus partículas.
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instrucciones: elige una respuesta y pulsa \siguiente\. recibirás tu pu…
Un cambio en la cantidad de energía
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3. reread lagos lines from pages 9 - 11: \others there are who... throw…
A. He is a schemer who will do anything to get wealth and money.
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c. name the following compounds or ions. identify each compound as mole…
Nitrogen trioxide, molecular #### ii) \(NO_3^-\)
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multiple - choice question waters ph of 7 is neutral acidic basic rewat…
neutral