化学
化学反应、化学计量、分子结构与元素性质。
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question 36 of 47 for the list of alcohols, rank the alcohols in streng…
Weakest → $\text{CH}_3\text{OH}$ → $\text{FCH}_2\text{OH}$ → $\text{F}_2\text{CHOH}$ → $\text{F}_3\text{COH}$ → Strongest
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for the list of compounds, rank the compounds in strength from weakest …
Weakest: $\text{H}_4\text{Si}$ $\text{H}_3\text{P}$ $\text{H}_2\text{S}$ Strongest: $\text{HCl}$
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part b: mass-to-mole 6. how many moles are in 36.04 g of water (h2o)? 7…
\(2\space mol\) ### Question 7:
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question 10 of 10 read the lines: that woman’s days were spent in ignor…
D. abcb
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question 3 of 10 which is the best definition of a rhyme scheme? a. rhy…
C. Rhymes used in a repeating pattern
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3. write the rhyme scheme for the following four lines from emily bront…
ABAB
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question 12 2 pts which of the following factors influence how soils de…
- living things that add organic matter to soils, and remove nutrients - water and rainfall - this weathers parent material and transports soil particles - rock parent material th…
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chemical equations are balanced when what quantity or quantities are th…
- The sum of masses of all substances involved. - The number of atoms of each kind.
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in the lab, jose has two solutions that contain alcohol and is mixing t…
700
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classify the following as a heterogeneous mixture (suspension), homogen…
homogeneous mixture (solution)
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compare the total mass of the reactants to the total mass of the produc…
B. $28\ \text{g}\ \text{N}_2 + 6\ \text{g}\ \text{H}_2 ightarrow 34\ \text{g}\ \text{NH}_3$
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only approved chemicals may be present at whataburger locations. solo l…
A. True Verdadero
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the whataburger hazard communication program binder contains a complete…
B. Chemicals Químicos
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determine the hybridization of the nitrogen atom and oxygen atom in ace…
1. N ($sp^3$); O ($sp^2$) 2. A line-angle structure with: a 5-carbon chain, a double bond between the first and second carbons, and three methyl branches attached to the fifth car…
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question 18 mark this question if you place an object on a balance and …
1
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question 17 butter melting is an example of a(n) ______ change. physica…
physical
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question 13 when an atom absorbs energy, it will likely enter into a(n)…
excited electronic state
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question 12 what is the correct name for cocl₂·6h₂o? ○ cobalt(ii) chlor…
cobalt(II) chloride hexahydrate
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question 11 which of the following is a metalloid? si p zn la
A. Si
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model a (a chemical structure diagram of methane) and model b (a 3d mol…
D. The angles at which atoms are arranged in the molecule
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2. look at the two models shown below. each represents a molecule of me…
D. The angles at which atoms are arranged in the molecule
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question 7 the chemical formula for nitrosyl fluoride is nof. in the le…
1
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question 6 mark this question which of these is more likely to be a gas…
C. $\text{SO}_2$
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question 6 mark this question which of these is more likely to be a gas…
C. $\text{SO}_2$
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question 5 mark this question which of the following is nonpolar and ha…
BeH₂
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17 drag and drop the words with the descriptions. the smallest unit of …
the smallest unit of an element that maintains all of the chemical properties of that element: atom an element that gains or loses an electron: ion an element that has a different…
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14. choose all that apply. which five postulates were proposed by dalto…
All atoms of a given element are identical. They have the same mass. However, atoms differ from other atoms in different elements by size, mass, and chemical properties. All matte…
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if reaction starts with 20g of reactants it should produce a total of 3…
B. a total of 20g of products (assuming the options are labeled A, B, C, D with B being "a total of 20g of products")
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the reaction below is an example of? $ce{agno_{3} + nacl = agcl + nano_…
B. Double Replacement
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oxidation- rocks that contain iron react with oxygen and form rust dest…
destructive (chemical weathering)
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fe + h₂so₄ --> fe₂(so₄)₃ + h₂; decomposition; synthesis (combination); …
Single replacement
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moss, lichens, and fungi create acid that breaks down rocks; constructi…
Destructive (chemical weathering)
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pb(no₃)₂ --> pbo + no₂ + o₂; single replacement; synthesis (combination…
Decomposition
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ch₄ + 2o₂ —— co₂ + 2h₂o which type of reaction is shown? combustion syn…
A. combustion
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which law states that matter cannot be created or destroyed, only rearr…
B. the law of conservation of mass
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the picture shows which type of reaction? options: combustion, single r…
D. synthesis
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which of the following general formulas represents a single - replaceme…
A. \(A + BC = AC + B\)
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5. how would you modify the procedure if another unknown ion was presen…
To modify the procedure for an additional unknown ion: 1. Determine the new ion’s chemical properties (charge, solubility, reactivity). 2. Select reagents that selectively react w…
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how many hydrogen (h) atoms are in nh₄os
The option with "4" (assuming the options are labeled, e.g., if the second purple box is labeled B, then B. 4)
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jin bought a heat pack that weighs 15 g. he shook it so it would releas…
15 g (corresponding to the option with "15 g")
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how many water molecules are in 5.2 moles of water? 5.2 3.1 × 10²⁴ 8.63…
\( 3.1 \times 10^{24} \) (corresponding to the option: 3.1 × 10²⁴)
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what type of reaction shows a substance breaking down into two or more …
decomposition
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which statement is not evidence that a new substance has formed during …
Substance melts
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ch₄ + o₂ → co₂ + h₂o balance and determine the coefficients 1, 2, 1, 2;…
1, 2, 1, 2 (corresponding to $CH_4$, $O_2$, $CO_2$, $H_2O$)
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what type of reaction has carbon dioxide and water as the products? com…
A. combustion
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what is the part of a chemical equation called? --> 2h₂o chemical equat…
C. Products
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a precipitate is a (select two) an aqueous solution a sign of a physica…
C. solid forming from two aqueous solutions, D. a sign of a chemical change
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n₂ + h₂ → nh₃ the equation is balanced... false true
False
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which represents a balanced chemical equation?\ $\\ce{co_{2} + 2h_{2}o …
B. $\boldsymbol{CH_4 + 2O_2 ightarrow CO_2 + 2H_2O}$
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fe₂o₃ + c → fe + co₂ balance the equation and determine the coefficient…
2, 3, 4, 2 (the third option: 2, 3, 4, 2)
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how many oxygen (o) atoms are in $2c_2ho_8cl_2$ options: 16, 8, 2, 5
16
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what is the definition for avogadros number? number of grams per one mo…
B. \(6.02\times10^{23}\) particles per one mole of a substance (assuming the blue option is labeled B; adjust the label as per the original question's numbering if different)
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20/40 which would have more atoms? 1 mole of si 1 mole of au 1 mole of …
None, all are equal
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read the passage. the pet food industry you have just adopted a pet, an…
Each heading presents an aspect of the pet food manufacturing and marketing process and explains how it affects the accuracy of information provided on pet food packaging.
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6. which of the following best illustrates the concept of the tragedy o…
D. Depletion of an aquifer by regional farmers ### Question 7
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part c thinking /10 create a procedure to carry out your experimental d…
### Procedure to Identify Substances (BaCl₂, Mg(NO₃)₂, K₂SO₄) #### 1. Experimental Design Rationale Use **chemical precipitation reactions** (based on solubility rules and ionic i…
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read the passage. the pet food industry you have just adopted a pet, an…
Each heading presents an aspect of the pet food manufacturing and marketing process and explains how it affects the accuracy of information provided on pet food packaging.
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the pet food industry you have just adopted a pet, and youre at a pet s…
It suggests a skeptical tone by questioning the reliability of information provided to consumers by pet food companies.
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13. if protons and neutrons have the same mass, what is the approximate…
The approximate mass of a proton and a neutron is 1 amu. ### Question 14
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based on the effective nuclear charge for the atoms shown in the slide,…
Even though the effective nuclear charge is the same, the attraction will decrease because the atoms are getting larger as you add more protons and electrons.
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based on the effective nuclear charge for the atoms shown in the slide,…
Even though the effective nuclear charge is the same, the attraction will decrease because the atoms are getting larger as you add more protons and electrons.
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solutions. write balanced equations to support your predictions. organi…
To solve this, we analyze each reaction using solubility rules: ### For \( \boldsymbol{BaCl_2} \) tests: 1. \( \boldsymbol{BaCl_2 + Na_2CO_3 ightarrow} \) - Products: \( BaCO_3 \)…
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chemicals in tobacco products quick check how does nicotine affect the …
increases heart rate
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chemicals in tobacco products quick check a person who hasnt smoked for…
withdrawal
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chemicals in tobacco products quick check the addictive chemical found …
nicotine.
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3. why is sodium ion chosen as the cation of all three solutions that w…
Sodium ion is chosen as the cation for ion - identification solutions mainly because: 1. Most sodium salts are soluble in water, so \(Na^+\) will not form a precipitate with the a…
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4. find the mass of iron (ii) sulphate needed to prepare 250ml of 0.600…
s: 4. The mass of iron (II) sulphate is \( \boldsymbol{24.33\ \text{g}} \) (using \( M = 162.2\ \text{g/mol} \)) or \( \boldsymbol{22.8\ \text{g}} \) (using anhydrous \( \text{FeS…
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volatile organic compounds (vocs): the most ______ of indoor air pollut…
1. common 2. paints, cleaning supplies, pesticides (or other relevant products) 3. so many different VOCs 4. formaldehyde
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12. $\\ce{cu + agno_{3}}$ $\\ce{ag + cu(no_{3})_{2}}$ answer: 13. $\\ce…
12. $\text{Cu} + 2\text{AgNO}_3 ightarrow 2\text{Ag} + \text{Cu(NO}_3\text{)}_2$ 13. $\text{Pb(NO}_3\text{)}_2 + 2\text{KI} ightarrow \text{PbI}_2 + 2\text{KNO}_3$ 14. $\text{HCl}…
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2. how do solubility rules help predict which reactions will produce a …
Solubility rules help in predicting precipitation reactions as follows: 1. For a reaction (usually double - displacement) involving ionic compounds, determine the possible product…
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sources of outdoor chemical hazards - in the air: ____________, such as…
- In the air: natural sources - In the ground: industrial waste (or oil leaks, based on the image) - In the water: runoff - Bioaccumulation: accumulation of a substance in an orga…
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covalent bond formation depends on the ability of atoms to donate elect…
D. share electrons with other atoms (assuming the options are labeled A - E with D being "share electrons with other atoms")
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question 1 of 5 which of these compounds can be expected to have the lo…
\( \boldsymbol{\text{C}_6\text{H}_{12}} \) (the option with \( \text{C}_6\text{H}_{12} \))
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learning goals - understand the properties of cations (positive ions) a…
1. A chemical reaction where two soluble ionic solutions are mixed, and their ions recombine to form an insoluble solid (precipitate) that separates from the liquid mixture. 2. So…
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instructions balance each chemical equation below. students may work fo…
1. $2\text{H}_2 + \text{O}_2 ightarrow 2\text{H}_2\text{O}$ 2. $\text{N}_2 + 3\text{H}_2 ightarrow 2\text{NH}_3$ 3. $\text{C} + \text{O}_2 ightarrow \text{CO}_2$ 4. $4\text{Fe} + …
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lewis structure for covalent compounds (remember octet 8) practice prob…
### Problem 1: \( \boldsymbol{F_2} \) #### Step 1: Determine Valence Electrons for Fluorine Fluorine (F) is in group 17, so it has 7 valence electrons. Since there are two F atoms…
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2) read the following graduated cylinders in milliliters. be specific! …
68 #### b.
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which element is an example of a metalloid? a gold b helium c d
D. silicon
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atom a has an atomic number of 19 and a mass number of 40. atom b has a…
B. Atom A has one less proton and one more neutron than Atom B.
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helium, neon, and argon are examples of a metals. b metalloids. c noble…
C. noble gases.
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the periodic table organizes elements according to increasing a atomic …
C. atomic number.
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the elements from this section of the periodic table all belong to the …
C. period.
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which word or group of words is represented by the word \period\ in the…
C. Energy Level
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which best describes the location of non - metals on the periodic table…
D. upper right corner
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using the periodic table and your knowledge of atomic structure. cobalt…
B. Cobalt has one less proton.
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place each statement in the column of the particle that it best describ…
**Protons** - positive charge found in the nucleus - periodic table is set up based on the number of these - gives the identity of the atom **Neutrons** - neutral charge and helps…
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the atomic number is considered a unique atom and element identifier. d…
B. The proton number remains constant through changing the atomic charge, energy, and isotopes.
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which of these are illegal or scam activities? check all that apply □ r…
- running a pyramid scheme - hacking to harm property - distributing a virus - hacking a computer
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balancing and types of reactions practice balance the equation: □al₂(so…
Balanced equation: $\boldsymbol{\ce{1 Al_{2}(SO_{4})_{3} + 3 Ca(OH)_{2} -> 2 Al(OH)_{3} + 3 CaSO_{4}}}$ Type of reaction: Double - displacement (or Double - replacement)
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balancing and types of reactions practice balance the equation: □al₂(so…
Balanced equation: $\boldsymbol{\ce{1 Al_{2}(SO_{4})_{3} + 3 Ca(OH)_{2} -> 2 Al(OH)_{3} + 3 CaSO_{4}}}$ Type of reaction: Double - displacement (or Double - replacement)
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balancing and types of reactions practice balance the equation: □ca(oh)…
Balanced equation coefficients: 1, 1, 1, 2. Type of reaction: Double - displacement (Neutralization)
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balancing and types of reactions practice balance the equation: □ca(oh)…
Balanced equation coefficients: 1, 1, 1, 2. Type of reaction: Double - displacement (Neutralization)
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be sure to read the information at the left before answering this quest…
in the atmosphere
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how is this substance classified? it has the formula nh₃. image of mole…
a compound
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which technique involves passing a mixture through a porous barrier to …
filtration
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what happens during the process of evaporation? liquid is added to diss…
Heat is applied to crystallize a dissolved solid and remove the liquid.
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which of these techniques can be used to effectively separate an undiss…
settling, then decantation
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what is the process that separates and crystallizes a dissolved solid, …
evaporation
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what technique would you use if you wanted to separate a mixture of iro…
magnetism
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what method would separate a mixture of iron filings and sugar most eff…
D. Use a magnet to attract the iron.