化学
化学反应、化学计量、分子结构与元素性质。
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carbon dioxide and water are produced when pentane ($c_5h_{12}$) reacts…
C. $\ce{C5H12(g) + 8O2(g) -> 5CO2(g) + 6H2O(g)}$
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barium chlorate (ba(clo₃)₂) breaks down to form barium chloride and oxy…
B. $\ce{Ba(ClO_{3})_{2}(s) ightarrow BaCl_{2}(s) + 3O_{2}(g)}$
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nh₃(g) + o₂(g) stackrel{pt}{→} no(g) + h₂o(l) what element is the catal…
D. Pt
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counting valence electrons how many valence electrons does this oxygen …
six
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aqueous magnesium chloride and hydrogen gas are produced when solid mag…
C. \( \text{Mg}(s) + \text{HCl}(aq) ightarrow \text{MgCl}_2(aq) + \text{H}_2(g) \) (Note: Assuming the third option is labeled as C, as per typical multiple - choice numbering whe…
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sulfur trioxide is a gas that reacts with liquid water to produce aqueo…
B. $\ce{SO_3(g) + H_2O(l) \to H_2SO_4(aq)}$
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identify the information that can be included in a chemical equation. c…
- the states of the reactants and products - the temperature and pressure at which the reaction was carried out - the relative amounts of reactants and products - the type of cata…
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which of the following is the correct word equation for the reaction de…
B. calcium hydride + water → calcium hydroxide + hydrogen
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which of the following is the correct word equation for the reaction de…
A. sulfuric acid + sodium hydroxide → sodium sulfate + water
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which of the following is the correct word equation for the reaction de…
D. mercury(II) oxide → oxygen + mercury (assuming the last option is labeled D; if the options are labeled differently, adjust the label but the equation is mercury(II) oxide → ox…
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which of the following is the correct word equation for the reaction de…
C. carbon monoxide + hydrogen → methanol (where the option is the third one in the list: carbon monoxide + hydrogen → methanol)
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click here to access the interactive simulation. you will practice bala…
(Level 1): 2 ### Level 2: Balancing \( \boldsymbol{\ce{C + H2O -> CH4 + CO2}} \)
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ye-jun is planning a study related to the impact of disasters. while __…
developing the hypothesis; theories
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which equation obeys the law of conservation of mass? h₂(g) + o₂(g) → h…
\( \boldsymbol{2\ce{H2}(g) + \ce{O2}(g) ightarrow 2\ce{H2O}(g)} \) (the third option: \( 2\ce{H2}(g) + \ce{O2}(g) ightarrow 2\ce{H2O}(g) \))
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how do balanced chemical equations show the conservation of mass? they …
The correct option is: They show that the number of atoms of each element is the same in the products and reactants.
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write the chemical formula for each of the following compounds. identif…
I, \(NiCl_2\) ### 12. copper (II) nitrate
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match the reaction on the right with the corresponding reaction on the …
Top - bottom: 2, 4, 3, 1 (i.e., the first box: 2, second box: 4, third box: 3, fourth box: 1)
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chemistry identifying compound names and formulas name: period: write t…
I, Ammonium Chloride ### Problem 3: $\boldsymbol{CuF}$
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what do the symbols tell you about the conditions of the reactions show…
- The products and reactants of both reactions are gases. - Reaction 1 occurs at high pressure. - A catalyst is used for reaction 2.
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chemistry identifying compound names and formulas write the name for ea…
Type: C, Name: dinitrogen trisulfide ### Problem 2: $\ce{NH_{4}Cl}$
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what is the chemical equation for the burning of propane if all the pro…
B. $\ce{C3H8(g) + 5O2(g) -> 3CO2(g) + 4H2O(g)}$
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propane burns in oxygen to produce carbon dioxide and water. what are t…
The formulas of the reactants are $\ce{C_3H_8}$ and $\ce{O_2}$. The formulas of the products are $\ce{CO_2}$ and $\ce{H_2O}$. (The third option in the given choices)
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la mayoría de los elementos del bloque d muestran estados de oxidación …
# Explicación breve: 1. El flúor (F) tiene un estado de oxidación fijo de -1, al ser un halógeno muy electronegativo. 2. Para el estado de oxidación +1 del cobre (Cu⁺), se equilib…
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select the word(s) to complete the word equation that matches the descr…
hydrogen + oxygen ### Second Reaction (Reaction of Magnesium with Oxygen)
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which of the following happens during a chemical change? check all of t…
- New substances with different properties are formed. - Solids, liquids, or gases may form.
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investigation 6 chemical bonding jewelers use gems in jewelry because o…
| Gems | Metals | |------|--------| | - Hard (high hardness, resist scratching) <br> - Brittle (break easily with force, show cleavage/fracture patterns) <br> - Distinct optical p…
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question 6 of 10 what should you do if you take a reading and find tds …
B. Blowdown the tower and add make-up water.
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select the description of each substance given by each chemical formula…
Since the dropdown options are not provided, I'll explain the expected answers based on chemical concepts: ### For "One molecule of \( \boldsymbol{O_2} \) is made of": \( O_2 \) i…
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3. a container holds three gases: oxygen, carbon dioxide, and helium. t…
$710.625 \text{ kPa}$ (or can be rounded to 711 kPa; if converted to other units: ~5.33 atm, ~5330 torr)
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the term \conductivity\ refers to: choose an option below electrical re…
B. the measurement of the concentration of dissolved solids in the water
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question 7 of 10 how often should building maintenance staff test basic…
daily
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what agricultural advantage is mentioned in the video when farmers enco…
C. It can reduce the need for chemical fertilizers and lower environmental impact
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b. in full sentences, what properties did you observe from the substanc…
1. The substance, milk, properties were a white, opaque liquid at room temperature, with this appearance resulting from fat globules and casein proteins scattering light. 2. The s…
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question an element with mass 390 grams decays by 19.5% per minute. how…
21.4 grams
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mixed up... the othe write the formula: 1. copper (ii) chlorate 2. calc…
$Cu(ClO_3)_2$ ### 2. Calcium nitride
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mixed practice! name the following: na2o caco3 pbs2 sn3n2 cu3po4 hgf2
s: - $\ce{Na2O}$: Sodium Oxide - $\ce{CaCO3}$: Calcium Carbonate - $\ce{PbS2}$: Lead(IV) Sulfide - $\ce{Sn3N2}$: Tin(II) Nitride - $\ce{Cu3PO4}$: Copper(I) Phosphate - $\ce{HgF2}$…
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radioactive compound with mass 240 grams decays at a rate of 30% per ho…
$C = 240(0.7)^4$
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mixed practice! name the following: 1. na2o 2. caco3 3. pbs2 4. sn3n2 5…
Sodium oxide #### 2. $\ce{CaCO_{3}}$
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part 2: classify the following substances as elements (e) or compounds …
E ### 8. Water Water has the formula $\ce{H_2O}$, made of hydrogen and oxygen atoms. It is a compound.
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part 1: classify the following as a substance (s) or a mixture (m). ___…
S ### 2. Trail mix Trail mix has various components (nuts, seeds, etc.) with variable amounts.
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2. an object placed in a graduated cylinder raises the volume from 12.2…
The volume of the object is \( 2.3 \, \text{mL} \) (or \( 2.3 \, \text{cm}^3 \)).
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1. find the volume of a box measuring 2 cm by 7 cm by 3 cm.
The volume of the box is \( 42 \, \text{cubic centimeters} \) (or \( 42 \, \text{cm}^3 \)).
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reread the first six lines of the sonnet. if the first line is identifi…
Line 2: b Line 3: a Line 4: a Line 5: b Line 6: b
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a sample of liquid water at 45.0°c is heated to a gas at 150.°c at a co…
$q = 4.18\ \text{J/mol·K} \times \text{mass} \times 55\ \text{K} + \text{moles} \times 40700\ \text{J/mole} + 2.11\ \text{J/mol·K} \times \text{mass} \times 50\ \text{K}$ *(Note: …
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ch₄ + o₂ → co₂ + h₂o
The balanced chemical equation is $\boldsymbol{CH_4 + 2O_2 ightarrow CO_2 + 2H_2O}$
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which steps will help you identify central ideas in a sonnet? choose th…
- finding a single idea or concept that links the big ideas in each quatrain - using context clues or a dictionary to define unfamiliar words - restating main ideas in my own words
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over a long period of time, different processes are involved in the for…
1. Water seeps down through the ground 2. Water drips into the cave through the cracks 3. Water evaporates and molecules move close together 4. Molecules join together to form cry…
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read the first five lines of shakespeare’s “sonnet 12,” and use the dro…
To determine the rhyme scheme, we analyze the end - sounds of each line: ### Line 1: "When I do count the clock that tells the time" Let's take the end - sound of this line. We'll…
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1. if 125 ml of a 0.15m naoh solution is diluted to a final volume of 1…
\( 0.13 \, M \) ### Question 2
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an atom with the same number of protons but a different number of neutr…
To solve this, we match each definition to the correct term: 1. **"An atom with the same number of protons but a different number of neutrons"** → Isotope (by definition of isotop…
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which statements about sonnets are true? choose four correct answers. s…
- The two types of sonnets are English (Shakespearean) and Italian (Petrarchan). - The sonnet form was invented in Italy, and then adopted by English poets. - Sonnets are a kind o…
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which statements about sonnets are true? choose four correct answers. s…
- B. The two types of sonnets are English (Shakespearean) and Italian (Petrarchan). - C. The sonnet form was invented in Italy, and then adopted by English poets. - D. Sonnets are…
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nd the atomic mass of various atoms. fill in the atomic mass of carbon …
The atomic mass of Carbon is 12 AMU, and the atomic mass of Aluminum is 27 AMU.
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ctice 2 the atomic mass of various atoms. fill in the atomic mass of ca…
The atomic mass of Carbon is: 12 AMU. The atomic mass of Aluminum is: 27 AMU.
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select all the correct answers. which of the following lines from of pl…
B. "But about the 16th of March a certain Indian came boldly amongst them, and spoke to them in broken English, which they could well understand, but marveled at it." C. "Being, a…
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6. how many grams of solute are in 250. ml of a 0.10 m cacl₂ solution? …
6) 2.8 g
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when a gas, that was not present before, is released as bubbles, it is …
True
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do the number of protons always equal the number of neutrons? if given …
No, the number of protons does not always equal the number of neutrons. ### Second Question: If given the atomic # of an element, what two other pieces of information do you also …
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scheme and rhythm in a sonnet by william shakespeare famous quotations …
- "To be, or not to be," → "that is the question." - "O Romeo, Romeo," → "wherefore art thou, Romeo?" - "To thine own self" → "be true." - "The course of true love" → "never did r…
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atomic # = atomic mass = # of protons = # of neutrons = # of electrons =
Atomic # = 16 Atomic Mass = 32.06 # of Protons = 16 # of Neutrons = 16 (or 16.06) # of Electrons = 16
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change in consistency is evidence of a physical change, not a chemical …
True
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color change is always evidence that a chemical change has occurred. tr…
False
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25 mn 54.938 atomic # = atomic mass = # of protons = # of neutrons = # …
### Manganese (Mn): - Atomic # = 25 - Atomic Mass = 54.938 - # of Protons = 25 - # of Neutrons = 30 - # of Electrons = 25 ### Fluorine (F): - Atomic # = 9 - Atomic Mass = 18.998 -…
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25 mn 54.938 atomic # = atomic mass = # of protons = # of neutrons = # …
s (filled for each element): ### Manganese (Mn): Atomic \# = 25 Atomic Mass = 54.938 \# of Protons = 25 \# of Neutrons = 30 \# of Electrons = 25 ### Fluorine (F): Atomic \# = 9 At…
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a chemical property can only be observed after a reaction has occurred.…
True
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in shakespeares as you like it, the following lines are an example of..…
1. connotation 2. Theme
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explain how to find the # of neutrons atomic mass protons 3 li 6.941 at…
(for each part): ### Lithium: Atomic # = 3 Atomic Mass = 6.941 # of Protons = 3 # of Neutrons = 4 # of Electrons = 3 ### Silicon: Atomic # = 14 Atomic Mass = 28.086 # of Protons =…
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5. the elution solvent can be safely poured down the sink drain? true /…
5. FALSE 6. FALSE
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7. blue light waves ______. fly right through the atmosphere, while the…
scatter more than other colors
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the number of protons in an atom * atomic mass atomic number
B. atomic number
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5. you find some soil that is mostly made of clay and silt, but no sand…
This soil most likely formed from intense chemical weathering of parent rock that reduced minerals to fine clay and silt, combined with water erosion or deposition processes that …
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how is noise pollution best described? airborne chemicals an unpleasant…
unwanted or disruptive sound
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what causes noise pollution? microplastics airborne chemicals vibration…
C. vibrations in the air (assuming the options are labeled A - D with A: microplastics, B: airborne chemicals, C: vibrations in the air, D: greenhouse gases)
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what causes noise pollution? microplastics airborne chemicals vibration…
C. vibrations in the air (assuming the options are labeled A: microplastics, B: airborne chemicals, C: vibrations in the air, D: greenhouse gases)
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how is noise pollution best described? an unpleasant scent or smell unw…
unwanted or disruptive sound
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what causes noise pollution? airborne chemicals microplastics vibration…
C. vibrations in the air (assuming the options are labeled A: airborne chemicals, B: microplastics, C: vibrations in the air, D: greenhouse gases)
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5 multiple choice 10 points predict the products for the following reac…
1. $\text{Br}_2 + \text{AlF}_3$ 2. $\text{H}_2 + \text{MgCl}_2$
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c. how many electrons does it have? 10. compare sodium (na) and chlorin…
Sodium (Na) #### Part 2: Which one is nonmetal?
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part c: application & critical thinking 9 oxygen has an atomic number o…
8 ### ii. How many electrons does it have?
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1. define ( r_f ) value. 2. a student performs this experiment and reco…
1. The $R_f$ (retention factor) value is the ratio of the distance a solute component travels to the distance the solvent front travels in a chromatography experiment, used to ide…
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part c: application & critical thinking 9. oxygen has an atomic number …
8 #### How many electrons does oxygen have?
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9. oxygen has an atomic number of 8. - how many protons does it have? _…
8 #### How many electrons does oxygen have?
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6 multiple choice 10 points what is the name of hf? hydrogen flouride f…
6. Hydrofluoric Acid 7. Lithium hydroxide
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4 multiple choice 10 points when aluminum reacts with copper (ii) chlor…
Cation (Copper)
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part b: periodic table basics 5. the vertical columns in the periodic t…
b) families/groups ### Question 6
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1. the smallest unit of an element that still has the properties of tha…
c) atom ### Question 2
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oxygen is acting as an oxidizing agent in all of the following reaction…
C. \(2 F_2(g) + O_2(g) ightarrow 2 OF_2(g)\)
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hcl + naoh → nacl + h₂o 25.0 ml of 1.00 m hcl is added to 75.0 ml of 1.…
\(-148\) (or more precisely \(-148.4\)) kJ/mol (Note: If we calculate \(\frac{-3710\space J}{0.0250\space mol}=\frac{-3.710\space kJ}{0.0250\space mol}=-148.4\space kJ/mol\), so t…
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create a molecular diagram below, then type the correct molecular shape…
Molecular diagram: O=N-O⁻ (with one lone pair on the central N atom) Molecular Shape: bent
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sodium - na how many protons? how many electrons? draw the electron orb…
### Sodium (Na) section: 1. How many electrons? $\boldsymbol{11}$ 2. How many electrons are in the outer energy level? $\boldsymbol{1}$ 3. This is called the $\boldsymbol{\text{Le…
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3. what qualities does the song suggest would make jackson a good presi…
The song suggests qualities like **alertness** (from "Jackson, he was wide awake"), **fearlessness toward trivial matters** (from "wasn’t scared of trifles"), **military/strategic…
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how many grams of f₂ are needed to produce 89 grams of fef₃?
Approximately 45 grams (or more precisely around 44.97 grams) of \( \text{F}_2 \) are needed.
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how many neutrons are there in cesium cesium-131 has a mass number of 1…
76 (corresponding to the option with value 76)
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beryllium (be) has an atomic number of 4 and an average atomic mass of …
5
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multiple-choice question what is the overall charge of \\(\\ce{_3^7li}\…
0
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how many protons are in calcium (ca); atomic number = 20; average atomi…
20
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determine the number of electrons in \\(\\ce{_{29}^{63}cu}\\)
29
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read the lyrics of this folk song, which was written in 1821 by samuel …
Two adjectives describing the song’s mood are "spirited" and "confident".
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use the answer bank to create a molecular diagram and identify the mole…
Molecular diagram: A central C atom bonded to 4 Br atoms, no lone pairs on C. Molecular Shape: Tetrahedral
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initial knowledge check question 10 a chemical technician measured the …
| Temperature (in °C) | Relative Frequency | |---|---| | 95 to 100 | 0.22 | | 101 to 106 | 0.17 | | 107 to 112 | 0.28 | | 113 to 118 | 0.33 |