化學
化學反應、化學計量、分子結構與元素性質。
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practice it! a guitarist is playing music in a band. every time he pluc…
sound energy
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question 2. in the periodic table below, label metals, nonmetals, and m…
Light blue squares: Metals; Pink squares: Non - metals; Blue squares: Metalloids
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which pair of atoms would form a covalent bond? calcium (ca) and bromin…
Oxygen (O) and chlorine (Cl)
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homework 10 - 09/25/2025 question 1. describe the general properties of…
Metals: Good conductors of heat and electricity, high luster, malleable, ductile. Non - metals: Poor conductors, may be brittle, lack metallic luster. Metalloids: Intermediate pro…
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two carbon atoms use the energy and bond formation simulation (link pro…
The H - H bond is stronger than the C - C bond. The C - C bond is not stronger than the H - H bond as stated in the incorrect part of the statement. The C - C bond is weaker becau…
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multiple choice 1 point the potential energy is a measure of the attrac…
The two hydrogen atoms have a lower potential energy indicating their bond is stronger than that of oxygen.
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drag and drop the words or phrases that accurately complete the paragra…
1. mechanical 2. light 3. chemical 4. thermal
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16. students are looking at the amount of organic matter in soil taken …
A line graph would show the changes between the variables of the amounts of organic matter and the depth.
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practice it! kristin was participating in the science fair this year. s…
chemical
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review it! some students were discussing and illustrating different way…
cooking cake batter to make cupcakes, starting a campfire
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review it! on independence day, a family watched fireworks at the beach…
C. sound and light
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5. how can you tell if the flame on a bunsen burner is getting too much…
The flame is blue in color.
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question 19 1 point the function of dendrites is to a control pain thro…
D. receive incoming signals from other neurons
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read the excerpts from lizzie bright and the buckminster boy. excerpt 1…
the only one for all the island's students.
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3. using dimensional analysis, calculate the mass, in grams, of hydroge…
$1.618\ g$
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9. what type of molecule is insulin?
Peptide
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elements, compounds & mixtures = hydrogen (element) = oxygen (element) …
Based on the definitions provided in the text, an element is a pure substance made of the same type of atoms (e.g., carbon, iron). A compound is a pure substance formed by two or …
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name a. an analogy is a statement that compares sets of words. write th…
1. weary 2. league 3. scheme 4. evening 5. chief 6. squeaky 7. deed 8. healer 9. zebra 10. sleek 11. wheeze 12. (no match) 13. speech 14. family 15. reef 16. indeed 17. breathe 18…
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when stirred, which two substances form a solution? a. sand and salt b.…
d. Sugar and water
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9) select the best answer. what is different about the earths chemical …
The Earth has an abundance of chemicals necessary for life and in the right proportions.
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6) select the best answer. most ______ comes to the earth from the sun …
6) C. energy 7) D. tilt
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wednesday a b c d which set of pictures shows what happens to a glass o…
# Explicación: ## Paso 1: Comprender la evaporación Cuando una copa de agua de sal se deja en un mostrador, el agua comienza a evaporar. Al principio, la copa está llena de agua d…
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a student makes a fruit drink by stirring a powdered mix into cold wate…
# Breve explicación: Una solución es una mezcla homogénea en la que un soluto (el polvo en este caso) se disuelve en un solvente (el agua). La disolución del polvo en el agua hace…
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people put sugar in their tea to make it sweet. the sugar will dissolve…
# Breve explicación: La disolución de un soluto (azúcar) en un solvente (té) es más rápida a altas temperaturas. Las moléculas del solvente caliente se mueven más rápido y ayudan …
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3. in which beaker of water will sugar dissolve the fastest?
# Explicación: ## Paso 1: Comprender la relación temperatura - disolución La disolución de un soluto, como el azúcar en agua, es más rápida a medida que aumenta la temperatura del…
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which of these is a mixture? a. salt b. water c. lemonade d. sugar
# Breve explicación: La sal es un compuesto químico (NaCl), el agua es una molécula (H₂O), el azúcar es un compuesto orgánico. La limonada está formada por agua, azúcar, jugo de l…
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directions: look around your home and list 5 different mixtures and 5 d…
| Mixture | Solution | |--|--| | Arena y agua | Sal en agua | | Cereales mixtos | Azúcar en café | | Salsa de tomate con especias | Vinagre en agua | | Mezcla de frutas | Alcohol …
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9. what happens during condensation?
A gas changes into a liquid as it loses heat energy and gas molecules come closer together.
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6. what is precipitation? 7. what temperature does water boil at? 8. wh…
6. The process by which a solid forms from a solution. 7. 100°C 8. Solid - state
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read the passage. the stinky durian fruit the durian is an asian fruit …
Scientists found that a combination of different chemicals is responsible for the durian's powerful odor.
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color by number erosion/weathering/deposition name: date: per: directio…
1. B. weathering [brown] 2. A. erosion [dark green] 3. C. deposition [purple] 4. C. both A & B [red orange] 5. C. deposition [light brown] 6. B. weathering [white] 7. A. erosion […
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09 question (1 point) yeast converts glucose (c₆h₁₂o₆) into ethanol (d …
$1C_6H_{12}O_6(aq)\longrightarrow2C_2H_5OH(l)+2CO_2(g)$
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copper was one of the earliest metals used by humans, because it can be…
Part 1: 2, 1, 4, 1 Part 2: 2, 1, 6, 1 Part 3: 1, 2, 1, 1
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3. est - ce que toutes les molécules qui contiennent de l’hydrogène ont…
Non, les molécules contenant de l'hydrogène n'ont pas toutes les mêmes propriétés et fonctions.
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each of the pairs of containers pictured below contains substances comp…
Part 1: X(g) + Y(g) → XY(g) Part 2: 2X(g) + 2Y(g) → X₂Y₂(g)
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i - ready determine word meaning - instruction - level d tricks. tip #1…
spit
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chemistry - unit 1 test 1. cubic centimeter is a unit used to measure a…
1. d. volume 2. a. mass 3. b. decreases 4. a. increases 5. Sketch the object at the bottom of the cylinder with new water - level $V_1 + 15cm^{3}$ (where $V_1$ is initial water - …
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6. which hazard requires specialized filter lenses in protective equipm…
6. d. Radiant energy 7. a. Conduct a thorough hazard assessment 8. c. Employers must provide them when needed 9. b. Safety glasses with side shields 10. c. Goggles with proper sea…
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osha eye and face protection requirements assessment 1. what is the pri…
1. b. ANSI Z87.1 standards 2. c. Allowing workers to use their personal sunglasses instead of safety glasses 3. b. Goggles 4. c. When exposed to splashes or flying debris 5. b. Th…
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select all the correct answers. two students are debating whether the w…
Water interacts with living organisms but not geological features. (False as it interacts with both) Water returns to its original state after completing the cycle. (False as it c…
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chemistry - unit 1 test 1. cubic centimeter is a unit used to measure a…
1. d. volume 2. a. mass 3. b. decreases 4. a. increases 5. Sketch object at bottom, new water - level at 45mL (assuming initial level at 30mL) 6. a. $340mL\times\frac{1L}{1000mL}=…
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multiple choice question what does an atomic number tell about an atom?…
B. The number of protons it has
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select the correct answer. the water cycle is a biogeochemical cycle th…
B. Water can change from solid to liquid at certain points in the cycle.
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19. what is the symbol for the element with atomic #82? 20. what is the…
19. Pb 20. Hydrogen 21. # p⁺: 20; # n⁰: 25; # e⁻: 20 22. # p⁺: 47; # n⁰: 61; # e⁻: 46 23. Krypton - 92 24. 83 25. 34
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13. what is the isotope name for a nucleus with 78 protons and 182 nucl…
13. Platinum - 182 14. Te 15. 50 16. # p⁺: 88, # n⁰: 135, # e⁻: Varies depending on the ion charge (usually 88 for neutral or adjusted based on charge) 17. Chlorine 18. # p⁺: 18, …
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7. what subatomic particles are in an uncharged isotope with atomic num…
7. # $p^{+}$: 10 # $n^{0}$: 17 # $e^{-}$: 10 8. Iridium - 171 9. 84 10. Mo 11. Radon 12. # $p^{+}$: 30 # $n^{0}$: 27 # $e^{-}$: 28
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1. what subatomic particles are in a zirconium (iv) ion if it has a mas…
1. - # $p^{+}$: 40 - # $n^{0}$: 65 - # $e^{-}$: 36 2. Aluminum - 27 3. - # $p^{+}$: 19 - # $n^{0}$: 21 - # $e^{-}$: 19 4. Mg 5. Cesium 6. 32
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19. which of the following is a physical property of a substance? flamm…
19. Density 20. Convection
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17. what is the purpose of a scientific model? to generate new laws and…
17. To represent phenomena, systems, processes, or solutions to engineering problems 18. Mass
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there are three isotopes of hydrogen. they are hydrogen-1 (sometimes ca…
They have the same atomic number, They have the same number of electrons, They have the same number of protons
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in what ways is an atom of carbon - 14 different than an atom of carbon…
A. carbon - 14 has a larger mass number, C. carbon - 14 has more neutrons
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fill in the blank fields below an atom of gallium - 70 has an atomic nu…
Atomic number: 31, Mass number: 70, Protons: 31, Electrons: 31, Neutrons: 39
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question list question 17 of 20 | total points: 15 out of 20 drag the w…
1. protons 2. electrons 3. mass number 4. neutrons
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question 16 of 20 | total points: 14 out of 20 nucleus of an isotope of…
Without seeing the specific content of the options clearly (assuming the pink represents a proton and green represents a neutron), isotopes of hydrogen have the same number of pro…
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complete the information for an atom of arsenic - 75. the atom has an a…
The atom has an atomic number of 33. It has 33 protons. The mass number of the atom is 75. Each atom of arsenic - 75 has 33 electrons and 42 neutrons.
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complete the information for an atom of cobalt - 60. the atom has an at…
The atom has an atomic number of 27. It has 27 protons. The mass number of the atom is 60. Each atom of cobalt - 60 has 27 electrons and 33 neutrons.
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10. a student is investigating how stirring affects the rate of dissolv…
A. Stirring
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complete the information for an atom of phosphorus - 30. the atom has a…
The atom has an atomic number of 15. It has 15 protons. The mass number of the atom is 30. Each atom of phosphorus - 30 has 15 electrons and 15 neutrons.
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a particular atom has seven electrons and eight neutrons. this is an at…
This is an atom of nitrogen. It has 7 protons. The mass number of the atom is 15.
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an atom that contains six protons must have a mass number of 12 must be…
B. must be a carbon atom
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an atom that contains six protons must have a mass number of 12 must be…
B. must be a carbon atom
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for an atom (which is neutral), which of these must be true? the number…
The number of protons is equal to the number of electrons
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e) how many neutrons are located in the nucleus of 14 - c?
8
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pick all of the physical changes * 2 points ice melting butter melting …
1. Pick all of the physical changes: Ice melting, Butter melting, Water boiling 2. Pick all of the chemical changes: Magnesium burning 3. Ice melting is a physical change because:…
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7 a chemist is developing a new type of battery. how would understandin…
It would allow them to maximize the efficiency of electrical energy generation and minimize energy loss within a closed system.
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choose one correct answer in each drop - down list. the proton has a ma…
The proton has a mass number of 1 and a charge of +1. The electron has a mass number of 0 and a charge of -1. The neutron has a mass number of 1 and a charge of 0.
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chemistry laboratory equipment (notes) what are some examples of filtra…
Coffee filters separating grounds from coffee; air filters in cars/homes removing dust; tea strainers separating tea leaves from tea.
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read the descriptions of rhyme schemes below. free verse: poetry that d…
A. free verse
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chemistry laboratory equipment (notes) what are some examples of filtra…
Examples of filtration: coffee filters, air filters. Heating solids: test - tube, test - tube holder, Bunsen burner setup. Heating liquids: beaker, wire gauze, ring stand, Bunsen …
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6. what are potential negative environmental impacts of the end - produ…
Degradation of water quality, Global climate change, Degradation of soil quality, Degradation of air quality
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which of the following statements is/are true about the region of the a…
It contains most of the volume of the atom It is the location of the electrons It is negatively charged
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calculate the average atomic mass of silver if 13 out of 25 atoms are s…
$107.96$ For the second - part of the problem:
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question list question 3 of 20 | total points: 2 out of 20 atom labeled…
It is positively charged, It is the location of the protons, It contains most of the mass of the atom, It is the location of the neutrons
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4. what factors affect the rate of a chemical reaction or dissolving? p…
4. Particle size, Stirring, Temperature, Concentration 5. Impulse, Momentum
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in what way are the lines of the weary blues similar to the lyrics of a…
The poem uses repetition to create meaning.
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atom labeled \x\ in the attached picture? it is neutral it contains mos…
It contains most of the mass of the atom, It is positively charged, It is the location of the neutrons, It is the location of the protons
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2. what methods can be used to organize quantitative and qualitative da…
2. A. Graphs, C. Tables, D. Charts 3. A. Radiation
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question list question 2 of 20 | total points: 1 out of 20 which of the…
It contains most of the mass of the atom, It is positively charged, It is the location of the neutrons
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which of the following is a chemical change? a) boiling water b) dissol…
1. c) Burning paper 2. b) Chemical change 3. b) Water vapor 4. c) Evaporation
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which of the following is an example of a 1 point physical change? a) b…
1. b) Melting ice 2. c) A physical change affects the appearance of a substance, while a chemical change alters its composition.
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model 1 - copper samples group number volume (cm³) mass (g) substance 1…
1. Copper 2. Group Number, Volume (cm³), Mass (g), Substance 3. Used a balance for mass and a volume - measuring device for volume of copper pieces. 4. Volume. Experimenters chose…
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2. sep analyze data complete the table with the mass number, number of …
| Element | Mass Number | $p^{+}$ | $n$ | $e^{-}$ | | ---- | ---- | ---- | ---- | ---- | | Fluorine | 19 | 9 | 10 | 9 | | Argon | 40 | 18 | 22 | 18 | | Calcium | 41 | 20 | 21 | 20…
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a certain drug is made from only two ingredients: compound a and compou…
159
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ela 10 a semester exam drag each item to the correct location to show t…
Villanelle: mostly three - line stanzas Ballad: all four - line stanzas, second line of each stanza rhymes, rhyme scheme of ABCB
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a student conducts an experiment to test how the temperature affects th…
A. the amount of sugar
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lete the sentences to explain why scientists were concerned about the u…
The first blank is "decrease" because CFCs react with ozone and deplete it. The second blank is "more" because with less ozone, less UV is absorbed and more can reach Earth.
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complete the sentences to explain why scientists were concerned about t…
1. decrease 2. more
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the passage below describes a process of scientific inquiry. select the…
She wondered if she could water her petunia plants with gray water.
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iron reacts with oxygen in a chemical hand - warmer. how should this re…
A. as an exothermic process because it releases heat
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the temperature of a sample of liquid water changes from 50°c to 30°c. …
The molecules move more slowly and their average kinetic energy decreases.
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which statement describes thermal energy? the energy that is associated…
the energy that is associated with temperature
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complete the text with the better conjunctive adverb. scientists believ…
Consequently
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reactant p contains 50 j of energy, and reactant q contains 35.3 j of e…
A. Energy is absorbed because the product has more energy than the reactants have.
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multiple choice question where are the electrons present in an atom? a.…
A. In different energy levels
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the passage below describes a process of scientific inquiry. select the…
He normally makes rock candy using white sugar but wondered if he could make larger sugar crystals using pure cane sugar.
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which statement describes mechanical energy? the energy that is stored …
the sum of the kinetic energy and the potential energy of an object
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an ice cube is dropped into a glass of milk at 20°c. which statement ex…
A. Because milk has higher KE than ice, KE is transferred from the milk to the molecules of ice.
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when ammonium chloride is dissolved in water, the beaker gets cold. whi…
B. endothermic
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18. i am in period 4 group 6. who am i? 19. i have 53 protons. who am i…
18. Chromium (Cr) 19. Iodine (I) 20. Neon (Ne) 21. Nickel (Ni) 22. Polonium (Po) 23. Hydrogen (H) 24. Americium (Am), 95 25. 4 26. Radon (Rn), 136 27. Bromine (Br) 28. Tin 29. Osm…
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which statement describes the law of conservation of energy? all system…
C. Energy cannot be created nor destroyed, but it changes from one form to another.