化学
化学反应、化学计量、分子结构与元素性质。
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multiple choice question an element is defined as a pure substance that…
C. a pure substance that cannot be broken down into simpler substances by a chemical reaction
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match each subatomic particle with the correct description of its charg…
Proton - Charged particle residing in the nucleus Electron - Charged particle residing outside the nucleus Neutron - Uncharged particle residing in the nucleus
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fill in the blank question a compound is a pure substance made up of at…
elements
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6) what causes the different colors? include the part of the atom invol…
1. Similarities: Both involve light emission from excited atoms. Differences: Flame tests are for element identification in lab, fireworks are large - scale displays. 2. Different…
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match each elemental symbol with the correct element name. instructions…
- Cl: Chlorine - Co: Cobalt - Ca: Calcium - Cr: Chromium - Cu: Copper
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fill in the blank question an element is a pure substance that cannot b…
chemical
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q1 chemistry: u2l12 electron config day 2 prepwork part 1: follow the e…
| Element | # e- | Full e- configuration | Orbital diagram | | ---- | ---- | ---- | ---- | | Lithium | 3 e- | $1s^{2}2s^{1}$ | $\frac{1\downarrow}{1s}\frac{1}{2s}$ | | Aluminum | …
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name: q1 chemistry: u2l12 electron config day 2 teacher: date: uncommon…
| # | Element | # e- | Full e- configuration | Orbital diagram | | ---- | ---- | ---- | ---- | ---- | | 1 | Lithium | 3 e- | $1s^{2}2s^{1}$ | $\frac{1\downarrow}{1s}\frac{1\downar…
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water has an uneven distribution of electrons. analyze the model of a w…
B. polarity
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which of the following results in water being an excellent solvent? wat…
Water molecules are polar and form hydrogen bonds with each other.
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below is a resonance structure for ch₃no. label the formal charges on t…
Oxygen: B. - 1 Carbon: C. 0 Nitrogen: D. + 1
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below is a resonance structure for no₃⁻. label the formal charges on th…
Nitrogen: D. +1; Double - bonded oxygen: C. 0; Single - bonded oxygen: B. -1
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below is a resonance structure for no3-. label the formal charges on th…
Nitrogen has a formal charge of +1. Single - bonded oxygen has a formal charge of - 1. Double - bonded oxygen has a formal charge of 0. So for the multiple - choice options, if we…
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7. answer the following questions regarding a h atom in which an electr…
$480\ nm$
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question 9 of 13 what is the primary function of a fume hood in a chemi…
To remove hazardous fumes and vapors
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question 8 of 13 what section of the safety data sheet (sds) provides p…
Prevention
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question 7 of 13 where in the safety data sheet (sds) would you find in…
B. Hazard identification
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question 6 of 13 which of the following solvents should be disposed of …
C. Dichloromethane (DCM)
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question 3 of 13 which hazard symbol indicates a chemical that can caus…
Corrosive
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question 2 of 13 to produce biodiesel, a batch of vegetable oil is proc…
B. Triglycerides, Methanol, and a Catalyst
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question 1 of 13 which process converts vegetable oils into biodiesel? …
B. Transesterification
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marie: i remember you struggled a bit with the hazard symbols. do you r…
A. A circle with flames
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list these elements in order of decreasing electronegativity. sr, be, c…
Be, Mg, Ca, Sr
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list these elements in order of increasing ionization energy. p, si, cl…
Si, P, S, Cl
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list these elements in order of decreasing atomic radius: ni, pt, ds, p…
Ds, Pt, Pd, Ni
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which of the following solvents would be disposed in the halogenated so…
B. Dichloromethane
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imagine the two following scenarios: 1. you pour a small amount of non …
d) 2. is worse than 1.
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well done! how should you dispose of the remaining methanol solution? a…
B. Into organic solvent waste
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there is some remaining sodium hydroxide - methanol solution that we ha…
d) Explosive
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part 3 (1 point) predict which of the two orders is preferred. choose o…
HOCl is the preferred arrangement.
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why is it important to work in the fume hood during this step? a) metha…
a) Methanol gets very volatile at high temperature
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3. ¿cómo hacen las compañías de refrescos para mantener más dióxido de …
3. c) Aumentando la presión 4. Aumentar la temperatura 5. Disminuye 6. Falso (El refresco se embotella a baja temperatura para mantener el dióxido de carbono disuelto)
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tarea de ciencias de séptimo grado tema: cambio de solubilidad pasaje d…
# Explicación breve: 1. Según el texto, para la mayoría de los solutos sólidos, la solubilidad aumenta a medida que aumenta la temperatura del disolvente. 2. El texto menciona que…
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24/34 adding soap to water ... increases the cohesion and hydrogen bond…
C. decreases the surface tension of the water by breaking hydrogen bonds, so the water can clean the greasy dishes.
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small insects can walk across the surface of calm water. their feet pus…
The insects are light enough so that they do not break the hydrogen bonds creating cohesion that hold the water molecules together
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all of waters unique properties (cohesion, adhesion, universal solvent,…
water is polar with a partial positive end and a partial negative end that attract other molecules.
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which of the following hazards does not apply for methanol? a) flammabl…
c) Oxidizing
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how would you write the conversion reaction from oil to biodiesel? a) o…
B. oil + alcohol + catalyst → biodiesel + glycerol + catalyst
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42) the name of kno₃ is potassium nitratide. 43) the law of constant co…
44) C. N = 1, H = 7, C = 2, O = 2 45) A. molecular compound 46) B. MgS 47) D. 16
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the table shows the number of students in each grade at prairie middle …
1. 80 students in the 8th grade study chemistry. 2. There are 100 students in the 8th grade. 3. First, find $\frac{1}{5}$ of the number by dividing the number by 5. Then multiply …
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a student draws this lewis structure for the neutral covalent species s…
Sulfur and oxygen have nonzero formal charges.
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when will the central atom in a covalent structure typically have an ex…
Surrounding atoms are much smaller than the central atom. Nonzero formal charges on individual atoms can be reduced. Surrounding atoms, for example oxygen or a halogen, are highly…
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a) provide the names for the following organic compounds: a) ch3c=chch=…
a) 6 - bromo - 2 - ethyl - 3,5 - octadiene b) 4 - fluoro - 2 - methyl - 1 - propylcyclopentene c) 5 - bromo - 6 - chloro - 2 - (phenyl) - 3,7 - decadiyne d) 2 - (tert - butyl) - 1…
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16) the standard si unit for temperature is: a) atmospheres. b) kelvin.…
16) B. Kelvin 17) B. 33.6 18) A. $1.75\times 10^{4}$ 19) A. 4.82 mL 20) A. $10^{-3}$ 21) T 22) F 23) T
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move the cards to match the name with the correct chemical formula. che…
SrS - strontium sulfide $Na_2SO_4$ - sodium sulfate $Na_2S$ - sodium sulfide $SrSO_4$ - strontium sulfate $SrSe$ - strontium selenide $Na_2Se$ - sodium selenide
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physical properties are characteristics that can be observed without ch…
The yarn ball is a solid.
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if the activation energy required for a chemical reaction were reduced,…
The rate would increase.
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take a look 1. identify the number of electrons in the outermost energy…
6
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part 4 (1 point) write the chemical formula of nitrous acid:
$HNO_2$
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1st attempt part 1 (1 point) give the name of hbr (include the word aci…
Part 1: Hydrobromic acid Part 2: Nitric acid Part 3: $H_3PO_4$
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before you read on the lines below, describe how you think chemistry re…
Chemistry is essential for understanding the composition, structure, and functions of living things as it deals with the chemical processes and substances within them.
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in this activity, you will explain what you just learned about where th…
False
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name these compounds. 1st attempt part 1 (1 point) ca₃(po₄)₂ part 2 (1 …
Part 1: Calcium phosphate Part 2: Magnesium perchlorate Part 3: Lithium nitrite Part 4: Sodium hypochlorite Part 5: Potassium permanganate
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which of the following is the correct line bond structure of the newman…
C
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1st attempt name the following polyatomic ion: so₄²⁻ ion
Sulfate
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which of the following compounds is meso? a. h3co2c - oh - oh - co2ch3 …
A. $H_3CO_2C - \underset{OH}{\overset{H}{\underset{|}{\overset{|}{C}}}}-\underset{OH}{\overset{H}{\underset{|}{\overset{|}{C}}}}-CO_2CH_3$
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identify the pair as being enantiomers or diastereomers. a. enantiomers…
B. diastereomers
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identify the pair as being enantiomers or diastereomers. a. enantiomers…
B. diastereomers
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look at these details from a paragraph about the same topic: • scientis…
Goggles are worn to protect people's eyes during different activities.
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state whether the each of the following is optically active or opticall…
B. active, inactive
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study this brochure from nasa, which explains in more detail the instru…
- measuring the amount of water in Jupiter’s atmosphere - taking images of the planet using infrared cameras - taking chemical “fingerprints” of Jupiter’s gases - mapping Jupiter’…
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match the wedge - dash formula with the correct fischer projection. a b…
A. Option Text
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look at these details from a paragraph about the same topic: • touching…
Coral reefs face various threats.
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match the fischer projection with the correct wedge - dash formula. ch3…
C
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saturated fats are typically solids at room temperature and unsaturated…
true
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read the passage. then, select the text that best helps you understand …
a physical process in which a solid changes directly to a gas
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each molecule below has one chiral carbon. determine the absolute confi…
B. R, S
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select all that apply select all the circumstances under which spectral…
Individual atoms radiating light Molecules radiating light Molecules absorbing light Individual atoms absorbing light
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assign the indicated chiral carbons as r or s. a. i: r ii: r b. i: r ii…
B. R, S
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1. a ____________ is a process in which one or more substances (the rea…
1. No se puede responder debido a que la pregunta 1 está incompleta. 2. B. Productos 3. Evolución de gas, cambio de color, formación de un precipitado 4. b. Enlaces químicos
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select all that apply select all the correct statements about spectral …
- Some spectral lines are not in the visible part of the electromagnetic spectrum. - Molecules can emit and absorb specific, unique colors of light. - Every hydrogen atom in a gas…
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drawn below is the structure of plavix® (clopidogrel), a medication use…
A. R-
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match each change of state with its description. sublimation boiling me…
sublimation - the process by which a solid becomes a gas boiling - vaporization that occurs below the surface of a liquid melting - the process by which a solid becomes a liquid e…
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holographers tower crime beat: even if flood city is the last city on e…
For "Who": Star - Guard, Chemical Baron base fleet members, victims of crimes. For "What": Reconnaissance flights by Chemical Baron, disputes with Star - Guard, muggings, theft of…
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which holds more solid solute: hot or cold liquids? which holds more ga…
1. Hot liquids hold more solid solute. 2. Cold solvents hold more gaseous solute. 3. Compressibility is the property of gases that allows them to be pressured into solution.
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assign the following as r or s. i a. r b. r c. s d. s ii a. r b. s c. r…
B. R, S
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name: mr. chino e what is the correct number for 7.58 x 10^-10? convert…
1. $0.000000000758$ 2. $\frac{365}{6}\approx60.83$ days per year 3. 110 feet per second 4. Approximately $11.16\ cm^{3}$ 5. Approximately $75187.97\ cm^{3}$ 6. Copper 7. Approxima…
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why is it important to wear safety goggles and gloves when working with…
It is important to wear safety goggles and gloves when working with NaOH (even low - concentration) because it is a strong base that can cause burns to eyes and skin. If NaOH come…
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determine the following as r or s. a. r r b. r s c. s r d. s s
B. R, S
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rank the following substituents from highest to lowest priority accordi…
D. IV > III > II > I
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give three ways to make sugar dissolve faster. which is the smallest pa…
1. Three ways to make sugar dissolve faster: Increase temperature, stir the solution, decrease particle size. 2. Smallest salt particle size: Finely powdered salt. 3. Largest suga…
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polar or non - polar? cooking oil soluble in water a compound with h’s …
Soluble in water: P Ionic Compounds: P A compound with H’s: P (sugar is an example here) Dissolves in water: P Insoluble in water: N - P
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name: trisha date: 9/30/ icients. 10. c₂h₅oh + o₂ → co₂ + h₂o 11. mg + …
$C_2H_5OH + 3O_2 ightarrow 2CO_2+3H_2O$; $Mg + 2HCl ightarrow MgCl_2 + H_2$
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question 1 - 9 review the following quote from machiavelli, the prince:…
A humanist approach that emphasized practical political analysis over idealism
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2.39 potassium has three naturally occurring isotopes (³⁹k, ⁴⁰k, and ⁴¹…
$^{39}K$ is more abundant.
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noemi is writing an essay on organic foods. she wishes to include prope…
She could summarize the ideas from the source. She could paraphrase the ideas from the source. She could directly quote the ideas from the source.
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creative writing 1203 unit review a. abstract thought b. allegory c. al…
(1) H. Epic (2) U. Philosophy (3) A. Abstract thought (4) CC. Syllogisms (5) Z. Short story (6) L. Imagery (7) AA. Simile (8) Q. Metaphor (9) T. Personification (10) J. Hyperbole …
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read the lines from the tide rises the tide falls. along the sea - sand…
It strengthens the connection between the two lines
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because of its rich blood supply, skeletal muscle is amazingly resistan…
1. atrophy 2. weakness 3. stimulated 4. muscles 5. aging
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a precious metal is a. an element with super and electric and thermal c…
C. an highly valuable element with super and electric and thermal conductivity, high luster, and sensitivity.
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roberto creates an animation titled \flying through an atom.\ the viewe…
The viewer travels through the electron cloud, then the nucleus.
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which part of an atom is mostly empty space? a. nucleus b. proton cloud…
C. electron cloud
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which of the following is not true of silver? a. it has the highest ele…
C. It is a copper alloy, usually mixed tin as the main additive.
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the venn diagram compares protons with neutrons. which shared property …
B. Has mass of 1 amu
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which of the following is true of iron? a. it has the highest electrica…
B. It can exist in many alloys, usually with a carbon base.
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what is the net charge of an atom that has six protons, seven neutrons,…
0
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which statement describes an atomic nucleus? an atomic nucleus is negat…
An atomic nucleus contains most of the atom's mass
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an atom with a neutral charge must have the same number of... protons, …
D. protons and electrons
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what is the atomic number of an element that has six protons, seven neu…
Six
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what is the mass number of an atom that has 6 protons, 7 neutrons, and …
B. 13