化学
化学反応、化学量論、分子構造、元素の性質。
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multiple - choice question which statement best describes each group of…
They all contain 1 oxygen atom and 2 hydrogen atoms.
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which of the following is true? this is an element, because its made of…
This is not an element, because it's made of more than one type of atom.
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the rhyme pattern that occurs at the ends of lines in poetry is called …
D. a rhyme scheme
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what are the characteristics of fixed poetry? select three options. a r…
a regular rhyme scheme lines of equal length a set number of lines
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question 5 what substances will you observe the spectra for? select all…
A. Carbon B. Sodium C. Bromine D. Nitrogen
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when is light emitted from an atom? when the nucleus absorbs energy whe…
When an electron goes from a higher energy orbital to a lower energy orbital.
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which property would xenon most likely have? it is stable. it is a soli…
It is stable.
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click on the link to go to the simul states of matter-p raise or reduce…
The state of matter is related to heat as adding heat can cause a substance to change from a solid to a liquid (melting) and then to a gas (vaporization), while removing heat can …
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phet simulation. click solid, liquid, or gas to observe the behavior of…
It changes by the balance between the molecules energy. The molecules in solids have low energy and are in fixed positions. In liquids, they have more energy and can slide past on…
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phet simulation. click solid, liquid, or gas to observe the behavior of…
The behavior of molecules changes in different states of matter due to the balance between molecular energy. Adding heat increases the energy of particles, which can cause a chang…
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the half - life of indium - 111 is 67.2 hours. how many milligrams of i…
1.56 mg
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conservation quick check what does the law of conservation of mass stat…
The total mass of all of the reactants prior to a chemical reaction must equal the total mass of all the products after the reaction.
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conservation quick check if the mass of elements before a chemical reac…
30 grams
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conservation quick check 78 g of potassium (k) react with 71 g of chlor…
149 g
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conservation quick check 2 grams of potassium (k) reacts with 5 grams o…
7 grams (corresponding to the selected option in the original multiple - choice question)
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conservation quick check which of the following equations demonstrates …
$CH_4 + O_2 ightarrow C + 2H_2O$
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practice: americium - 241 is a radioactive isotope used in smoke detect…
$^{241}_{95}Am ightarrow^{237}_{93}Np + ^{4}_{2}He$
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question 16 what is the stretching frequency (in cm⁻¹) of the following…
1655
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what stretching frequencies (in cm^-1) are present in the structure bel…
all of these
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the proper protective equipment for working with hazardous chemicals in…
T
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you have been asked to write an essay about the effects of large amount…
Thesis statement: Americans consume large amounts of sugar in their daily diets, which leads to a variety of health problems. Supporting details: - The average American eats or dr…
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fume hoods are used to ________ a. prevent fires from spreading in the …
C. prevent toxic gases from spreading through the lab
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what is the stretching frequency (in cm⁻¹) of the following carbonyl? 1…
1715
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what stretching frequencies (in cm⁻¹) are present in the structure belo…
1800
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gas behavior gas pressure is a measure of the collisions of the molecul…
The gas pressures are: 760 mmHg, 900 mmHg, 585 mmHg.
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aspartame: a has a low sweetness relative to sucrose. b has a trade nam…
# Breve explicación: El aspartamo es un edulcorante artificial ampliamente utilizado en bebidas sin azúcar debido a su gran dulzura. Es mucho más dulce que la sacarosa (sucrosa), …
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chemistry - unit 1 - worksheet 4 dimensional analysis in the space belo…
2. 8.32×10^{-2} kg(\frac{10^{3} g}{1 kg}) = 83.2 grams 3. 55.5 mL(\frac{1 cm^{3}}{1 mL}) = 55.5 cm^{3} 4. 0.00527 cal(\frac{1 kcal}{10^{3} cal}) = 5.27×10^{-6} kilocalories 5. 9.5…
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what is the stretching frequency (in cm⁻¹) of the following carbonyl? n…
1715
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recap/review 3.1 and 3.2 ws 1. if the accepted value is 8.8 and experim…
1. Percent Error: $44\%$ a) Calculator answer: $6.85\text{ cm}$, Answer with sig. figs: $6.9\text{ cm}$ b) Calculator answer: $3.374\text{ cm}$, Answer with sig. figs: $3.37\text{…
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3. a student has a pool of water at 25 degrees c and a bucket of water …
a) Neither. The average speed of particles is the same because temperature is the same for both. b) Neither. The average energy per particle is the same because temperature is the…
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chemistry—unit 2 review energy think of energy as a quantity that is al…
1a) False 1b) True 1c) False
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what is the stretching frequency (in cm⁻¹) of the following carbonyl? 1…
1655
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part 1 pennies and water question 1: how many drops of water did fit on…
1. Surface - tension is demonstrated. 2. The surfactant in soap reduces water's surface - tension, causing different results.
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1. what property or properties of water is demonstrated by this activit…
1. The property of water demonstrated by this activity is surface tension. Water molecules have cohesive forces due to hydrogen - bonding, which causes them to stick together and …
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what stretching frequencies (in cm⁻¹) are present in the structure belo…
1745
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a student conducts an experiment to test how the temperature affects th…
the temperature of the water
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which of the structures have a major peak between 1700 and 3000 cm⁻¹? (…
The first structure (acyl chloride)
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which of the structures have a major peak between 1700 and 3000 cm⁻¹? (…
The first structure (acyl - chloride)
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what is the stretching frequency (in cm⁻¹) of the following carbonyl? 1…
1745
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a. the diameter of the sun is approximately 1.391×10⁶ kilometres. the d…
a. Approximately 109 Earths could fit along the diameter of the sun. b. There are approximately $5.487\times 10^{40}$ water molecules in Lake Ontario. c. Approximately $1.714\time…
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which of the following is correct about icl a the name is iodine monoch…
A. The name is iodine monochloride and not monoiodine monochloride because the "mono" for the first cation - like element is dropped.
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chemistry review & practice worksheet density & significant figures - s…
1. $7.6$ g/mL 2. $8.36$ g/cm³ 3. $11.0$ g/mL 4. $4.25\times10^{-4}$ kg 5. $3.5\times10^{-4}$ kg 6. $1.25\times10^{-3}$ kg 7. $\$43.05$ 8. $\$3.75$ 9. $\$1.80$ 10. Section 13 11. S…
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a compound between p and br is ____ in nature and formed from ______ of…
D. covalent, sharing
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what stretching frequencies (in cm⁻¹) are present in the structure belo…
E. all of these
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the center section of the period table is classified into ___ elements.…
A. transition
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what are the horizontal (from left to right) parts of the periodic tabl…
B. periods
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the term periodic helps identify __________ that occur in the table, li…
C. patterns
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the vertical columns in the periodic table are called a families b peri…
A. families
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as you move from left to right across the periodic table, the number of…
A. Increases
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varies from family to family on the periodic table a reactivity b speci…
A. Reactivity
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elements in a family have the same ______________. a total number of el…
C. number of valence electrons
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a is the name for a vertical column in the periodic table. a family b p…
A. family
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properties of water 13 what is water made of? h2o 14. what does polar m…
15. Oxygen atom. 16. Oxygen has partial negative charge; hydrogen has partial positive charges. 17. Hydrogen - bond. 18. High specific heat, cohesion, adhesion, surface tension, g…
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in geology, weathering refers to processes that break down rocks into s…
physical weathering
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2. consider the following reaction to answer the questions below: 8zn(s…
The limiting reactant is \(Zn\).
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the models show the chemical structures of a fatty acid and a monosacch…
| | Fatty acid | Monosaccharide | |--|--|--| | Is a building block of triglycerides | Yes | No | | Contains hydrogen | Yes | Yes | | Has carbon atoms arranged in a ring | No | Yes…
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question 5 what stretching frequencies (in cm⁻¹) are present in the str…
1715
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what is the stretching frequency (in cm⁻¹) of the following carbonyl? o…
1655
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the profit, in dollars, made by selling x bottles of 100% all - natural…
The number of bottles $x$ must satisfy the interval $[10,30]$. So, the largest interval containing all possible answers is $[10,30]$.
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the profit, in dollars, made by selling x bottles of 100% all - natural…
25
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if you drop an object from twenty feet, it might shatter on the floor. …
Chemical potential energy
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2. a compound is analyzed and found to contain 68.54% carbon, 8.63% hyd…
2. Molecular formula: $C_{8}H_{12}O_{2}$, Empirical formula: $C_{4}H_{6}O$ 3. Empirical formula: $C_{3}H_{6}O_{2}$ 4. Empirical formula: $CH_{4}N_{2}O$
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layla mixed flour and water, and the flour clumped together in the wate…
Using a coffee filter
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note: round your ratio of moles to the nearest whole number as long as …
Empirical formula: $C_{4}H_{6}O$; Molecular formula: $C_{8}H_{12}O_{2}$
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part b: write the nuclear symbol (11 - 15) write the full nuclear symbo…
11. $_{15}^{31}P$ 12. $_{19}^{39}K$ 13. $_{82}^{207}Pb$ 14. $_{6}^{12}C$ 15. $_{92}^{235}U$
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part c arsenic express your answer in complete form, in order of increa…
$1s^22s^22p^63s^23p^64s^23d^{10}4p^3$
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read the text. chemists have various tests to learn about unknown subst…
pH test
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for a science experiment, mr. duncan mixed 0.00055 pounds of sulfur and…
B. $1.59\times 10^{-3}$ pounds
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complete the graphic organizer to describe the signs that indicate a ch…
| Sign of Chemical Change | Example | |--|--| | Change in color | Toast turning black when burnt | | Production of gas | Vinegar and baking - soda reaction producing carbon - diox…
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which three elements are found in every carbohydrate? phosphorus nitrog…
oxygen, carbon, hydrogen
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nickel express your answer in complete form, in order of increasing orb…
1s^22s^22p^63s^23p^64s^23d^8
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read the text. solutions are combinations of two or more evenly mixed s…
precipitate
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which three elements are found in every lipid? some lipids contain addi…
Hydrogen, Carbon, Oxygen
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1. a compound consists of 72.2% magnesium and 27.8% nitrogen by mass. w…
The empirical formula is $Mg_3N_2$
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chemical changes read the text and use a highlighter to identify: - the…
- Sentence defining chemical change: In a chemical change, one or more new substances are formed. - Two examples: Burning a match; Rusting - Sentences explaining the process: Duri…
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part d: mixed practice (21 - 25) 21. an isotope of hydrogen with 2 neut…
21. $_{1}^{3}H$ 22. $_{92}^{238}U$ 23. $_{20}^{40}Ca^{2 + }$ 24. $_{33}^{75}As$ 25. $_{35}^{80}Br$
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the mass of a hydrogen atom is about 1.67e - 24 grams. the mass of a pl…
C. $2.43\times10^{2}$
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name elfidio mejía date 9/18/25 a. percentage composition percent compo…
1. For \(H_2O\): \(\%H\approx11.19\%\), \(\%O\approx88.81\%\) 2. For \(Al_2(CO_3)_3\): \(\%Al\approx23.07\%\), \(\%C\approx15.46\%\), \(\%O\approx61.47\%\) 3. For \(C_6H_{12}O_6\)…
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who wrote the love of money is the root of all evil? saint christopher …
1. C. Saint Paul (the Apostle Paul) 2. C. Au
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changing state describe what happens to the energy and speed of particl…
Heating a substance: Increases; move faster Cooling a substance: Decreases; move slower For the drawing: - In the solid state (ice), draw $H_2O$ particles closely packed in a regu…
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complete the table. | | stearin | triolein | |--|--|--| | is a saturate…
| | stearin | triolein | |--|--|--| | is a saturated fat | Yes | No | | is likely solid at room temperature | Yes | No | | is an unsaturated fat | No | Yes | | is likely liquid at…
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triglyceride). stearic acid how many molecules of stearic acid are need…
3
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complete the table to compare triglycerides, phospholipids, and sterols…
| | Triglycerides | Phospholipids | Steroids | |--|--|--|--| | have carbon atoms arranged in long chains | Yes | Yes | No | | have carbon atoms arranged in rings | No | No | Yes |…
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learning goal 1. describe physical changes in terms of the arrangement …
Matter is composed of tiny particles called atoms. In elements, all atoms are of the same type, such as carbon, oxygen, iron, or gold. In compounds, atoms of different types are b…
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select the true statements. in steroids, carbon atoms are arranged in r…
In steroids, carbon atoms are arranged in rings; Steroids contain oxygen atoms; Steroids are chemical messengers.
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phospholipids are another type of lipid. they are the building blocks o…
- Carbon atoms are arranged in two long chains in phospholipids. - Phospholipids contain nitrogen and phosphorus atoms.
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physical change and particles describe what happens to particles during…
All matter is made up of tiny particles called atoms. In elements, the atoms are all the same type, such as carbon, oxygen, iron, or gold. In compounds, atoms of different types a…
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question 5 which of the following is used to calculate the vapor pressu…
B. mole fraction
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question 9 why does adding a non - volatile solute change the boiling p…
The solution needs a higher temperature to match its vapor pressure with atmospheric pressure.
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question 8 when a non - volatile solute is dissolved in a solvent, it m…
A. increase, decrease
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question 7 what is boiling point? the temperature of a burner on which …
the temperature at which the vapor pressure of a liquid is equal to the atmospheric pressure
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select the polysaccharide.
The top - most structure is the polysaccharide.
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question 6 which factor is not considered in determining colligative pr…
Type of solute
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question 4 why is the vapor pressure of a solution lower than that of a…
The solution has a lower number of solvent molecules evaporating.
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select the true statements. maltose has the same number of carbon atoms…
1. Maltose has the same number of carbon atoms as sucrose and lactose. 2. Maltose, lactose, and sucrose all contain glucose. 4. Maltose is found in rye and barley.
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question 3 what role does a non - volatile solute play in the vapor pre…
It decreases the vapor pressure.
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compare the chemical structures of lactose and sucrose. | | lactose | s…
| | lactose | sucrose | |--|--|--| | has 12 carbon and 11 oxygen atoms | Yes | Yes | | is a disaccharide | Yes | Yes | | contains the monosaccharide fructose | No | Yes |
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question 2 which of the following is a colligative property change in a…
Vapor pressure lowering
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in plant cells, glucose and fructose can react to form sucrose. plants …
- Disaccharides are made by joining two monosaccharides. - Plants with high levels of sucrose are used to make granulated sugar.
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question 1 what is a colligative property? a property of a liquid that …
a property of a solution that depends on the number of particles dissolved