化学
化学反应、化学计量、分子结构与元素性质。
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solute crystals are added to a solution until they begin to sink to the…
D. supersaturated
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under which conditions will sugar most likely dissolve fastest in a cup…
C. sugar crystals with stirring at 15°C
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a chemist has dissolved a certain substance in water. the chemist knows…
unsaturated
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which is true about dissolving a polar substance in water? ○ the solven…
B. The solute particles are carried into the solution.
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which statement best describes a true solution? a true solution will se…
C. A true solution will not separate in a centrifuge.
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which best describes the tyndall effect? ○ the scattering of light by s…
D. the scattering of light by particles in a mixture
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which is a characteristic of a solution? ○ its particles scatter light.…
B. Its particles are evenly distributed.
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mixture a was made by mixing different components together, but it appe…
B. solution
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in which situation can a mixture always be called a solution? when one …
D. when the mixture is homogeneous (assuming the options are labeled A to D as per typical multiple - choice, with the last option being D)
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legal age and limit for blood alcohol content is....... * 4 points ○ 21…
C. 21; .08 (assuming options are labeled A, B, C as first:21;.03, second:21;.09, third:21;.08) ### Second Question (Alcohol effects)
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milk is a heterogeneous mixture that contains different types of partic…
colloid
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which of the following is a homogenous mixture? ○ blood ○ steel ○ cloud…
B. steel
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which solution is a homogeneous mixture? ○ sand and water ○ salt and wa…
B. salt and water
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which is a characteristic of a homogeneous mixture that is a liquid? ○ …
It cannot be separated using filtration.
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review questions: 1. what facility provides care in a patient’s home? 2…
Home health care agency ### Question 2
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there 4,000-7,000 of these chemicals found in this substance. * pills c…
B. Cigarettes ### Second Question:
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read the passage. there are several questions about this passage. from …
4. Synthetic fibers are prone to static charge buildup, and nanoparticle technologies have been developed to help synthetics resist this buildup of static electricity.
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read the passage. there are several questions about this passage. atoms…
4. It uses wordplay to signal a transition from the specific situation of cats to a general explanation of the principles involved in static electricity.
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read the passage. there are several questions about this passage. from …
2. It describes the structure of strands of human hair when they are dry and how the structure changes when hair gets wet.
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read the passage. there are several questions about this passage. from …
2. By incorporating humor, the author keeps readers engaged with a scientific topic that might otherwise seem challenging.
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use the periodic table to answer the question. electronegativity chart …
B. HCl, H₂S, PH₃
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properties unit test what is the ph of a (1 \times 10^{-4}) mol hcl sol…
4
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properties unit test a small amount of sodium hydroxide is added to wat…
The negative log of the concentration of \( \text{OH}^- \) ions is 2. Sodium hydroxide is a strong base.
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properties unit test ammonia is a weak base. potassium hydroxide is a s…
A. A solution of potassium hydroxide will always have more \( \text{OH}^- \) ions than a solution of ammonia.
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question 6 (5 points) listen an atom has 35 protons, 35 neutrons, and 3…
D) 70
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metal reactivity lab - name: name date: ______________ purpose: to obse…
Since no specific question is provided about this Metal Reactivity Lab (e.g., predicting reactions, analyzing results, etc.), it's not possible to give a targeted answer. If you w…
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14b (unit 1) b. perform the following operations. find the calculator a…
### Part b #### i. \( 2.8 \times 10^{-3} \cdot 6.32 \times 10^{-5} \) # Explanation: ## Step1: Multiply coefficients and exponents To multiply numbers in scientific notation, we m…
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how many neutrons are in phosphorus? * 20 16 13 15 how many electrons a…
16 (corresponding to the option "16") ### Second Question: How many electrons are in a neutral element of Calcium?
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how many electrons are in a neutral element of calcium? * 20 19 21 22 w…
A. 20
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how many electrons are in a neutral element of calcium? * 1 point 20 19…
20
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what characteristic do alkaline earth metals share? * they have 1 valen…
39 ### Second Sub - Question: What characteristic do Alkaline Earth Metals share?
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which family contains elements that exist as two gases, one liquid (br)…
Halogens ### Second Question (Which family of elements has exactly one valence electron and is highly reactive with water?):
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what is the atomic number for iron (fe)? ○ 80 ○ 45 ○ 26 ○ 2 how many va…
26 (assuming the option with 26 is one of the choices, likely the third option as per the given choices: 80, 46, 26, 2) ### Second Question: Valence electrons in Group 2 (Alkaline…
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related to... memory (hg) among the...? ○ its the most... ○ its a liqui…
Boron ### Second Question (What is the chemical symbol for Antimony? )
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how many electrons are in a neutral element of calcium? * 20 19 21 22 h…
A. 20 ### Second Question: How many protons are in the element Fluorine?
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what product is north carolina’s top export? ○ machinery ○ textiles ○ c…
Chemicals (the option with "Chemicals") ### Second Question (US's number 2 manufactured export):
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which group is known to commonly bond with group 17 (halogens)?* ○ nobl…
C. Alkali Metals ### Second Question: How many electrons are in a neutral element of Calcium?
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what product is north carolina’s top export? ○ machinery ○ textiles ○ c…
Chemicals (the option with "Chemicals") ### Second Question (US's number 2 manufactured export):
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there is the implication, or indication, that if tania doesnt do well o…
C. a clear suggestion
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15 multiple choice 5.25 points how does the pork industry help the nort…
D. By providing jobs for citizens ### Question 16
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directions: use the graph to answer the questions graph: solubility vs.…
3, 71$\underline{7}$ #### d. 0.150
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cam and rosario decided to perform an experiment on the oxidation of me…
This experiment is missing a testing and data phase. Without a testing phase, their conclusion is based on the work of other people.
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co₂ noₓ h₂o co o₂ fuel e. is the flame in the image a result of a chemi…
28g
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question 1 of 20 : select the best answer for the question. 1. combinin…
D. Bismuth
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question: hans christian oersted, a danish chemist and physicist, disco…
magnetic field (or magnetism)
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question: what device converts the energy of a chemical reaction direct…
Fuel cell
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in a normal atom, the negative charges of the electron ____ the positiv…
balance (or are equal to)
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grammar passage 31 franciss father was jan baptist van helmont, the fle…
B. physician, innovator, diplomat, and religious thinker,
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looking for patterns in household objects/chemicals object/chemical | o…
The subfield is Chemistry (Natural Science). For substance classification: Elements have atoms, molecules have their molecules, mixtures have multiple molecules/atoms.
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object/chemical | observations | mixture/molecule/element | molecules/a…
10. Sulfur powder is an element
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exam lesson name: chemistry exam number: 700700rr ▶ exam guidelines ▶ e…
A. consist of a particular proportion of hydrogen and oxygen.
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exam lesson name: chemistry exam number: 700700rr ▶ exam guidelines ▶ e…
A. halogen.
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21. the carbon cycle includes two main categories of processes. some th…
A. A reduction in the consumption of fossil fuels
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unit 1 test review 1 • vocabulary, lab techniques, & safety name 14a (t…
The mixture shown in the image is a heterogeneous mixture.
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exam lesson name: chemistry exam number: 700700rr ▶ exam guidelines ▶ e…
C. Some of them explode when exposed to water.
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grammar passage plastic pollution is globally distributed across all oc…
D. large derelict nets, docks, and boats
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question 17 of 20 : select the best answer for the question. 17. which …
A. \(MgCl_2\)
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exam lesson name: chemistry exam number: 700700rr exam guidelines exam …
A. decomposition
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question 15 of 20 : select the best answer for the question. 15. which …
A. The atom has 7 protons and 7 electrons.
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exam lesson name: chemistry exam number: 700700rr ▶ exam guidelines ▶ e…
C. a base and an acid.
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question 12 of 20 : select the best answer for the question. 12. when t…
C. The law of conservation of energy
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13. what property of water allows water such as the ocean to store larg…
Versatility as solvent
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exam lesson name: chemistry exam number: 700700rr ▶ exam guidelines ▶ e…
A. \( \text{KOH} + \text{H}_2\text{SO}_4 ightarrow \text{KHSO}_4 + \text{H}_2\text{O} \)
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12. which statement is true? electrons are larger than protons. light o…
The statement "The number of protons in an atom determines the element" (the one with [light purple]) is true.
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exam lesson name: chemistry exam number: 700700rr ▶ exam guidelines ▶ e…
C. zinc and hydrochloric acid.
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question 8 of 20 : select the best answer for the question. 8. which of…
D. Has a negative charge when involved in chemical reactions
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exam lesson name: chemistry exam number: 700700rr ▶ exam guidelines ▶ e…
A. fusion.
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masteryconnect wilson, mak yla dtal: ch-term 1 - unit 1 assessment - 25…
43.0 mL
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exam lesson name: chemistry exam number: 700700rr ▶ exam guidelines ▶ e…
C. atomic number.
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exam lesson name: chemistry exam number: 700700rr exam guidelines exam …
B. the lanthanide series and the actinide series.
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exam lesson name: chemistry exam number: 700700rr exam guidelines exam …
C. Carbon
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exam lesson name: chemistry exam number: 700700rr ▶ exam guidelines ▶ e…
D. \( \text{CO}_2 + \text{C} ightarrow 2\text{CO} \)
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masteryconnect wilson, mak yla dtal-ch-term 1 - unit 1 assessment - 25-…
The student should remove flammability from the data table as it is not a physical property.
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exam lesson name: chemistry exam number: 700700rr exam guidelines exam …
D. valence.
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a simple starting carbon compound, the ____, is repeated to make a poly…
monomer
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which homologous series consists of hydrocarbons with double bonds and …
A. Olefins (alkenes)
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ethyl alcohol and methyl ether have the same molecular formula but enti…
B. Show their different arrangements with structural formulas.
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which of the following are used to preserve fruits and vegetables or as…
B. Polyvinyl plastics
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which of the following are used to preserve fruits and vegetables or as…
Polyvinyl plastics
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you would want a controlled-fusion power reactor near the ocean because…
Protium
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how are vertical control rods used in a nuclear reactor? answer options…
C. They're moved in and out of the reactor to control the chain reaction. (Note: Assuming the options are labeled A, B, C, D with the third option being C. If the original labelin…
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what element is used to study fertilizer absorption yet is used in canc…
Radiophosphorus
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a car rusting and a fuel exploding are examples of chemical reactions h…
different rates (or different speeds)
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c₃h₈ + o₂ → h₂o + co₂ + heat is an example of a/an ____ reaction.
combustion (or exothermic, but combustion is more specific for this hydrocarbon - oxygen reaction)
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whats missing from this chemical reaction that shows the combustion of …
The release of heat with the products
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which reaction is an example of a balanced endothermic reaction? answer…
A. $\ce{N_{2}(g) + O_{2}(g) + heat -> 2NO(g)}$
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which reaction is an example of a balanced endothermic reaction? answer…
A. $\ce{N_{2}(g) + O_{2}(g) + heat -> 2NO(g)}$
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which reaction is an example of a balanced endothermic reaction? answer…
A. $\ce{N2(g) + O2(g) + heat → 2NO(g)}$
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which of the following factors will slow down the rate of reaction? ans…
B. Decreased temperature
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____ are variations in the ways atoms can be configured in a solid samp…
Allotropes
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the law of ____ of matter states that matter cant be created or destroy…
conservation
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in a ____ reaction, two elements or radicals change places with two oth…
A. double - replacement
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which of these carbon structures is almost always man-made? answer opti…
Fullerene
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whats the formula for magnesium chloride with the valences balanced? an…
\(Mg^{+2}Cl^{-1}_2\) (or if considering the formula without showing charges but balanced, \(MgCl_2\); but based on showing valences (charges) and subscript, \(Mg^{+2}Cl^{-1}_2\) i…
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whats the formula for magnesium chloride with the valences balanced? an…
\(MgCl_2\) (corresponding to the option with \(MgCl_2\) among the given choices)
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nonelectrolytes are substances that dont dissociate into ions and are n…
electricity
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in ____ elements, the outermost shell of an atom contains half the numb…
metalloid
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____ tend to break apart in water to form a hydroxide ion. answer optio…
Bases
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____ salt is produced when hydrogen atoms from the acid are replaced by…
Normal
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10. diana y mike iban a llegar tarde a su próxima clase. después de apr…
Consecuencias incluyen riesgos de seguridad (exposición a sustancias tóxicas, quemaduras, intoxicación), errores en experimentos, desorden en el laboratorio, y posibles lesiones o…