化學
化學反應、化學計量、分子結構與元素性質。
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13. next, you will consider possible reaction #3. balance the chemical …
The coefficients (in order) are 2, 1, 2, 1.
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12. here is the summary of the two solids remaining if reaction #2 occu…
### Solid Remaining: Na: 1.79 g C: 0.933 g ### Total mass of solid produced: 2.72 g
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11. recall that there are 0.0777 moles $\text{nahco}_3$ reacting. calcu…
0.0777 mol C
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10. recall that there are 0.0777 moles $\\text{nahco}_3$ reacting in th…
0.0777 mol
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a lizard egg needs a temperature of 26-30°c to hatch properly. you plac…
D. Calcium chloride because it will create an exothermic reaction.
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9. next, predict the mass of the solid that would remain if reaction #2…
The coefficients (from left to right) are 2, 2, 1, 2, 3. The solid products are $\text{Na}(s)$ and $\text{C}(s)$; their total molar mass per 2 moles of $\text{NaHCO}_3$ is $(2\tim…
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chemistry unit 3 – quiz 1 practice 13. (5 pts) calculate the percent ab…
Percent abundance of Lutetium-175: \(97.40\%\) Percent abundance of Lutetium-176: \(2.60\%\)
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8. you calculated that 0.0777 moles naoh will remain if reaction #1 occ…
$3.108\ \text{g}$
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7 a cook had a jar containing a sweet food and a jar containing a sour …
A. The sweet food changed because the molecules were able to move fast enough to overcome the attraction between them. Its molecules now move away from each other.
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6 scientists digging in a cave found an unknown substance. the scientis…
a. into the substance, and the substance changed into a gas.
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5. a scientist has a container with a substance inside. at first, the m…
b. Before, the substance was a gas. Later, it was a liquid.
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7. use the equation built in the previous problem. calculate how many m…
0.0777 moles
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3. divers found two substances at the bottom of the ocean. at room temp…
a. weaker attraction between its molecules than Substance 2. Its molecules now move in place.
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6. construct the mole ratio needed to calculate how many moles of naoh …
Filled conversion: $0.0777\ \text{mol NaHCO}_3 \times \frac{1\ \text{mol NaOH}}{1\ \text{mol NaHCO}_3} = 0.0777\ \text{mol NaOH}$ Final moles of NaOH: $0.0777$
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9. classify the following changes as physical or chemical. a. boiling b…
a. Boiling: Physical change b. Crumpling: Physical change c. Burning: Chemical change d. Freezing: Physical change e. Evaporating: Physical change f. Rotting: Chemical change g. R…
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5. you can now convert the student response moles $ce{nahco_{3}}$ to mo…
$\text{NaHCO}_3(s) ightarrow \text{NaOH}(s) + \text{CO}_2(g)$ The coefficients are: 1, 1, 1
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4. you measured the mass of the baking soda ($nahco_3$) to be 6.53 gram…
$0.0777$ moles (rounded to three significant figures)
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heres the dimensional analysis setup from the previous problem: $14.3 \…
7.15 moles of $\text{O}_2$
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1 multiple choice 2 points what is the answer, with the correct number …
109.30 g ---
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4. when two nonpolar molecules are compared, we should consider the num…
1. Question 4: Butane, $\text{C}_4\text{H}_{10}$ 2. Question 5: Butane has the greatest number of electrons of the three molecules, making it the most polarizable. More polarizabl…
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the truth about tobacco what is in tobacco? a single puff of cigarette …
### What Is In Tobacco? NICOTINE: **addictive stimulant** drug found in **tobacco** CARBON MONOXIDE: A **colorless, odorless**, poisonous **gas** produced when tobacco burns. TAR:…
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determining charge an element becomes a positively charged ion when it …
loses electrons.
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practice: 5. explain the difference between physical properties and che…
- **Physical Properties**: Characteristics observable without changing the substance's chemical composition. Examples: Density ($\frac{\text{mass}}{\text{volume}}$), color, meltin…
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which sentence contains a metaphor? ○ the track star ran the race as fa…
B. The basketball player was a giant next to the small boy.
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explain. 8. can two atoms of the same element ever have different atomi…
No, two atoms of the same element cannot have different atomic numbers. The atomic number is the number of protons in an atom's nucleus, and this number uniquely defines an elemen…
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an element with mass 640 grams decays by 7.3% per minute. how much of t…
360.4 grams
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the electro-magnetic connectionhow do electromagnets work?what do a wre…
1. A length of conductive (usually copper) wire, a piece of metal, and a source of electricity. 2. When current is introduced, it flows through the wire, creating a magnetic field…
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part: 1 / 2 part 2 of 2 what would happen to the molarity of the soluti…
The molarity of the solution in the flask would be lower than the calculated value.
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select the single best answer for each part. part: 0 / 2 part 1 of 2 af…
Use a funnel through which the solid is poured into the flask, then rinse the funnel to ensure all is added to the flask.
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select the single best answer for each part.part: 0 / 2part 1 of 2after…
Pour the solid from the weighing vessel directly into the flask, then rinse the weighing vessel to ensure all residual solid is added to the flask.
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part: 0 / 2 part 1 of 2 after measuring the mass of a solid in a weighi…
Pour the solid from the weighing vessel directly into the flask, then rinse the weighing vessel to ensure all residual solid is added to the flask.
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after measuring the mass of a solid in a weighing vessel, what are the …
○ Pour the solid from the weighing vessel directly into the flask, then rinse the weighing vessel to ensure all residual solid is added to the flask.
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use the diagrams below to answer questions 1- 3.propanemethanoic acid1.…
1. | Substance | Boiling Point | Intermolecular Attractive Force(s) | |-----------------|---------------|-------------------------------------| | Propane | 229 K | London dispersi…
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an oxygen atom picks up two additional, free-floating electrons. is the…
Negative
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which characteristic increases the rate of a solute dissolving in a sol…
D. stirring solutions
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four students in a class explained how the size of the solute or temper…
Sophia and Christian
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i am a noble gas. i can be found in the same period as the lightest of …
Argon (Ar)
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the amount and ability of substance that can be dissolved by another su…
Solubility
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a physical law that states that matter is not created or destroyed duri…
Law of Conservation and Mass
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word:with prefix meaning \same\ used to describe solutionssiftingsolute…
homogeneous
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a method of separation that changes a liquid to a gas leaving behind di…
C. Evaporation
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3. 4 for each statement, write whether each describes a generic drug or…
### Question 3: 1. Generic 2. Brand-name 3. Brand-name 4. Both ### Question 4: You should not mix Tylenol with alcohol. Alcohol inhibits the liver's ability to metabolize acetamin…
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method used to sort liquids from non liquids usually done using a filte…
B. Filtration
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words used to tell how strong a solution is based on the amount of solu…
D. Concentration
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method of sorting object by buoyancy (ability to sink or float in water…
A. flotation
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chasity whitney chapter 8 summarize the situation with the wood and the…
### VOCABULARY - censure: To criticize harshly - conciliatory: Intended to make peace - machinations: Schemes, often sneaky ones - skulking: Hiding or moving secretly - unscathed:…
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a student combines water and salt in beaker a and combines sand and soi…
Beaker A contains a solution, and beaker B contains a mixture.
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a chef mixes oil and water in a bowl to make a salad dressing. what wil…
The oil and water will remain separate in the bowl and create a mixture.
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a teacher mixes salt and gravel in a bowl of water and stirs the mixtur…
The provided model is incorrect. A correct model would: 1. First show the removal of all gravel (diamond symbols) from the mixture of salt, water, and gravel. 2. Then show the rem…
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a student makes four mixtures and records his observations in a table. …
The salt is soluble in water.
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a teacher demonstrates an activity to show how different objects intera…
Sugar dissolves in water, and sawdust floats on water.
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lemonade is made by dissolving sugar and lemon juice in water. water is…
Lemonade is a mixture, and water is a compound.
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a 58.0 g sample of unknown composition was carefully analyzed and found…
$\text{C}_6\text{H}_9\text{O}\text{N}_5$
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a chemical compound composed of nitrogen and oxygen was carefully analy…
$\text{N}_2\text{O}_3$
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need a closer look? view this ph scale on desmos.table 1 shows the amou…
3. D. The pH of a solution is lower after the titration because of the addition of an acid. 4. C. The pH changes in the opposite direction and the colors would be reversed.
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3. hypochlorous acid and hypochlorite when considered together are also…
3. c. free chlorine 4. b. Chlorine dioxide
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5. acetic acid has a melting point of 16.6°c and a boiling point of 117…
A labeled heating curve for acetic acid is structured as follows (description, which can be translated to a graph): - **X-axis**: Heat Added (increasing left to right) - **Y-axis*…
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9. if a material has a high electron affinity, what will occur when it …
The object with higher electron affinity will gain an electron and end up negatively charged, while the object with a lower electron affinity will loose an electron and end up pos…
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4. describe the movement of the particles at the boiling point of a sub…
When a substance is at its boiling point: 1. **Temperature**: The temperature of the substance remains constant, even as more thermal energy is added. 2. **Energy**: The added the…
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sealing of cuts in skin by blood clotting:when the skin is cut, blood v…
The blood clotting cascade proceeds as follows: 1. Vessel/skin damage activates platelets and releases tissue factor (TF), which binds to factor VII to form TF:VIIa. 2. TF:VIIa ac…
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date 2/11/26 student #____you must create a bohr model for each atom, i…
| | protons | neutrons | electrons | |---|---|---|---| | 6. $^{22}_{11}\text{Na}$ | 11 | 11 | 11 | | 7. Fluoride ion, $\text{F}^-$ | 9 | 10 | 10 | | 8. Magnesium ion, $\text{Mg}^{…
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chemical reactions task cards created by teamwork toolbox (2017)chemica…
$\text{B}_2\text{Br}_6 + 6\text{HNO}_3 ightarrow 2\text{B(NO}_3\text{)}_3 + 6\text{HBr}$ ---
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which of these statements about airplane and rocket flight is true? a. …
B. Only one requires air molecules to generate lift.
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a rocket uses an engine that creates thrust through the combustion of a…
A. Chemical rocket
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3/15 what is the result of the reaction between potassium bromide and a…
B. no precipitate is formed
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2/15 which of the following compounds is soluble? strontium carbonate p…
potassium carbonate
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which term below describes the study of how energy is transferred to di…
A. Thermodynamics
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which change does nitrogen undergo oxidation? a. $ce{no_{2} -> n_{2}o_{…
D. $\text{NH}_3 ightarrow \text{N}_2$
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multiple-choice question how do you determine the number of neutrons? p…
Mass # - Atomic number
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1. which type of reaction? $ce{mg + 2hcl -> h_{2} + mgcl_{2}}$synthesis…
1. Single Replacement 2. A: Reactants; B: Yield Sign; C: Product 3. Ca: 3 atoms, C: 12 atoms, H: 18 atoms, O: 12 atoms 4. $4\text{P} + 5\text{O}_2 ightarrow 2\text{P}_2\text{O}_5$…
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multiple-choice question what happens if you heat up a liquid? it becom…
A. It becomes a gas.
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6 protons if carbon is neutral, then how many electrons should it have?…
6
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energy level # of electrons 1 2 2 8 3 18 what is the maximum number of …
8
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multiple-choice question which element is in the second period of the p…
D. Carbon
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which of these elements is not present in $\text{nano}_3$? nitrogen sod…
hydrogen
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1/10 how many total elements are in the chemical formula $ce{fe_{2}(no)…
3
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find the element: protons: 8 neutrons: 9 electrons: 8
Oxygen (O)
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what needs to be added for a solid to turn into a liquid and then gas? …
energy
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6/10 how many total atoms are in the chemical formula $\text{c}_3(\text…
9
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how many atoms of hydrogen are in this compound? 2 4 3 1
A. 2
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1/10 how many atoms are there total in $ce{h_{2}so_{4}}$? 5 3 7 6
7 (corresponding to the orange option with the number 7)
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what is it called when a liquid turns into a solid? vaporization freezi…
freezing
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2/10 how many oxygen atoms are in $ce{al_{2}(so_{4})_{3}}$? 1. 12 2. 7 …
1. 12
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multiple-choice question what is it called when a gas changes into a li…
condensation
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1. list the factors that affect chlorination of drinking water? 2. desc…
1. The factors affecting drinking water chlorination are: pH level, water temperature, chlorine dosage, contact time, presence of organic matter, water turbidity, and presence of …
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multiple-choice question what is it called when a liquid changes into a…
vaporization
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7. drew added yeast and sugar to room temperature water and placed it i…
B. The mass of the flask/balloon after the reaction should be the same as before the reaction since matter is neither created nor destroyed.
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multiple-choice question what is it called when a solid changes to a li…
melting
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6. students are given a sample of an unknown material. they want to per…
burning it producing a change in thermal energy
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5. a chemical formula is shown below: $(nh_4)_3po_4$ how many atoms, in…
20
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what are the charges of the following transition metals?iron (ii) _____…
### Ion Charges: Iron (II): $+2$ Tin (IV): $+4$ Cobalt (II): $+2$ Palladium (I): $+1$ Lead (II): $+2$ Copper (I): $+1$ Vanadium (IV): $+4$ Platinum (II): $+2$ Manganese (III): $+3…
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use your periodic table to predict the charges of the following ions: b…
$\text{Be}^{2+}$, $\text{I}^-$, $\text{Ar}$, $\text{Na}^+$, $\text{Cl}^-$, $\text{Ca}^{2+}$ $\text{O}^{2-}$, $\text{K}^+$, $\text{F}^-$, $\text{S}^{2-}$, $\text{P}^{3-}$, $\text{M…
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study the chemical equation. na + cl₂ → nacl is the chemical equation p…
No. There are two chlorine atoms on the reactant side and only one chlorine atom on the product side.
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4. the chemical formula for methane is $\text{ch}_4$. which statement d…
Four molecules of methane would contain 4 atoms of carbon and 16 atoms of hydrogen.
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1. the best friends club uses \invisible ink\ to write notes to each ot…
chemical change
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9. which of the following groups contains members with similar chemical…
9. C. Cu, Ag, Au 10. B. C, N, O
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3. based on the balanced chemical equation below, how many grams of $hg…
48 g
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answer the following questions over the relatedness of elements in the …
1. B silicon 2. C strontium 3. H helium 4. B lithium 5. D iodine 6. C helium 7. B phosphorous 8. D tin
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a spill occurs in the lab. the teacher asks whether it was a compound o…
It is a mixture because compounds do not separate on their own.
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romeo and juliet act 1 scene 5 sonnet analysisname: aynadavostep 1: ass…
### 1. Yellow (Religious Imagery) - Underline these phrases: - holy shrine - gentle sin - blushing pilgrims - Good pilgrim - mannerly devotion - saints - pilgrims' hands - holy pa…