Química
Reacciones químicas, estequiometría, estructuras moleculares y propiedades.
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select the correct answer. dorothy works as a medicinal chemist in a ph…
D. to research molecules in spider venom for new pain medication
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directions: select the correct element on the periodic table. select th…
Kr (Krypton)
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according to this phase diagram, how would you classify this as? hetero…
heterogenous mixture
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select the correct answer from each drop-down menu. an element has an a…
The element has $\boldsymbol{7}$ protons and $\boldsymbol{9}$ neutrons.
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4. add a neutron to your previously built atom. what does adding the ne…
- the mass of the atom ### Question 5 (Adding an electron)
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mgso₄ would be classified as compound element mixture
A. compound
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multiple-choice question f₂ is classified as compound element mixture
Element (the option with "Element" text, assuming the checkbox next to it should be selected, and the answer is the option "Element" among the choices: compound, Element, mixture)
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make the following changes to the simulation make sure to open the mass…
- the name of the element changes - the mass of the element changes - the charge of the element changes
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the formula agf would be classified as... element compound mixture
B. compound
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2 multiple choice 1 point box b represents which phase of matter? solid…
C (Gas)
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select the correct answer in each row. atomic number mass number atomic…
To solve this, we analyze each row by recalling the definitions of atomic number, mass number, and atomic mass: ### Row 1: Isotopes are included - **Atomic Number**: Same for isot…
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14 which of the following best describes the earliest model of the atom…
A. Atoms are indivisible. C. Atoms are hard spheres.
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if you were wanting to separate sand from a mixture of salt water and s…
filtration
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after reviewing todays material, the following to the best of your know…
A. Solid
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qn 13. the mass number on the periodic table tells you number of proton…
D. number of protons and neutrons (assuming the last option is D, if the options are labeled as A, B, C, D with the last one being "number of protons and neutrons", then the answe…
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q 12. how many protons and neutrons are in one atom of ( ce{^{30}_{14}s…
14 protons and 16 neutrons (corresponding to the first option: 14 protons and 16 neutrons)
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taylor’s family has a history of mental health problems. which factor m…
B. They had chemical imbalances in their brains.
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11. which of these particles have the heaviest mass? select two correct…
B. $\boldsymbol{_4^9Be}$, E. $\boldsymbol{_8^{16}O}$ (assuming options are labeled as A: $\ce{_1^1H}$, B: $\ce{_4^9Be}$, C: $\ce{_2^4He}$, D: $\ce{_{-1}^0e}$, E: $\ce{_8^{16}O}$)
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10. particles in a gas are far apart relative to their size. this prope…
C. Gases are highly compressible.
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multiple-choice question salt water is considered a mixture because it …
Homogeneous Mixture
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multiple-choice question does an exothermic reaction absorb or release …
B. release (assuming the second option is labeled B; if the first option was A and the second is B, then the answer is B. release)
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q 9. any atom that is electrically neutral must contain -- fewer neutro…
The correct option is the one with "equal numbers of electrons and protons" (the fourth option in the list).
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multiple-choice question 7. does an endothermic reaction absorb or rele…
The correct option is the one with "absorb" (the second option, assuming the first is "release" and the second is "absorb" as per the visible text). So, if we consider the options…
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q 7. a certain atom has a nucleus containing seven protons and eight ne…
B. nitrogen (assuming the options are labeled with letters, if not, just "nitrogen" as the correct option)
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is oxygen a gas or a vapor? vaopr gas
B. gas (assuming the second option with "gas" is the correct choice, and the first option has a typo "vaopr" instead of "vapor")
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multiple-choice question 6. ______ energy is stored in chemical bonds. …
A. potential
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chart (80 points) please list all of the factors of production for each…
Land supplies raw materials (wool, cotton, fibers, dyes) and physical spaces (sheep pastures, cotton fields, factories, water source). Labor (sheep/cotton farmers, factory/retail/…
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multiple-choice question 5. what is the symbol for heat? h q delta
B. q (assuming the options are labeled as A. H, B. q, C. Delta)
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physical properties table with substances: mercury (liquid, silver/whit…
water (assuming the options are water and ethanol/ethanal, and based on the table's data where water is colorless liquid with freezing point 0, so when it freezes, it's water)
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how does therapy help in the treatment of depression? a. changes negati…
A. changes negative thinking patterns
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multiple-choice question water and copper are considered a pure substan…
A. they are made of the same substance
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10. bromine has two isotopes, bromine-79 and bromine-81, whose masses (…
### Part A: Protons, Neutrons, Electrons Calculation #### Step 1: Protons (Atomic Number) Bromine has an atomic number of 35, so both isotopes have 35 protons. For Bromine - 79: \…
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4. which isotope represents an atom with 6 protons, 6 electrons, and 8 …
\( \boldsymbol{_8^{12}O} \) (Note: There may be a typo in the options, as the correct isotope should be \( _6^{14}C \) with 6 protons, 8 neutrons, and mass number 14. However, bas…
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for each of the following elements, draw lewis dot diagrams and arrows …
s (Corrected/Completed): 1) Formula: \( \boldsymbol{\text{NaCl}} \); Name: **Sodium Chloride** 2) Formula: \( \boldsymbol{\text{KI}} \); Name: **Potassium Iodide** 3) Formula: \( …
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q 3. the student pictured below is about to go into a chemistry lab. 1.…
- Tie back long hair (the student's long hair is loose, not tied back, which is a safety hazard in a lab as hair can catch fire or interfere with experiments). - Wear safety goggl…
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3) magnesium + oxygen mg o. mg^+2 :o:^-2 formula: mgo name: magnesium o…
Formula: $\boldsymbol{CaCl_2}$ Name: $\boldsymbol{calcium\ chloride}$
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2. students are provided a sample of an element with a table describing…
The average atomic mass is approximately $\boldsymbol{28.09}$ amu (rounded to four significant figures, considering the percent abundances and atomic masses).
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how many protons and neutrons are in one atom of silicon-30? 14 protons…
A. 14 protons and 16 neutrons
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level 4 q4 which of the following is the correct chemical formula for g…
B. \( C_6H_{12}O_6 \)
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for each of the following elements, draw lewis dot diagrams and arrows …
1. For Sodium + Chlorine: - Lewis dot transfer: $\text{Na} \cdot + : \overset{..}{..} \overset{..}{.}\text{Cl} : ightarrow \text{Na}^+ + [: \overset{..}{..} \overset{..}{.}\text{C…
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rachel carson helped usher in the modern environmental movement in the …
D. pollution and toxic chemicals
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5. use the periodic table to answer the following questions: t/i-6 for …
- Group: 16 (or 6A) - Period: 3 ### Part (b)
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physical and chemical properties & changes worksheet physical property:…
To solve this, we classify each property as physical (observed without changing substance) or chemical (involves chemical change): ### 1. Magnetic - **Physical Property**: Magneti…
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compound 1 has a composition of 46.7 mass % of element a and 53.3 mass …
To solve this, we use the law of multiple proportions. First, find the ratio of masses of B that combine with a fixed mass of A (or vice versa) for Compound I and the candidate co…
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lecture activity no. 1 since we only have a 1-hour class schedule, this…
The formula mass of $\ce{CaCl2}$ is $\boldsymbol{110.98\ \text{g/mol}}$ (or approximately $111\ \text{g/mol}$). ### Question 3:
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which best describes the structure of the poem \safari day in kenya\? ○…
D. free verse with varied line lengths
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43 when baking soda is added to vinegar, a chemical reaction occurs. th…
The total mass of baking soda and vinegar must equal the total mass of carbon dioxide and the liquid solution.
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4. calculate the number of protons, neutrons, and electrons for each of…
- For $\boldsymbol{^{35}_{17}\text{Cl}}$: Protons = 17, Neutrons = 18, Electrons = 17 - For $\boldsymbol{^{40}_{20}\text{Ca}}$: Protons = 20, Neutrons = 20, Electrons = 20
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consider the location of chlorine (cl) on the periodic table. which ele…
Fluorine (F) or Bromine (Br) or Iodine (I) or Astatine (At) (elements in the same group as chlorine, Group 17, the halogens, have similar chemical properties)
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test name: pmtc 37 which action demonstrates a chemical change? evapora…
Cooking an egg (because cooking an egg involves the denaturation of proteins, which is a chemical change, while evaporating water, shredding paper, and breaking a stick are physic…
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8. what is the difference between \mass number\ and \average atomic mas…
- **Mass Number**: Sum of protons and neutrons in a specific isotope's nucleus (whole number, e.g., C - 12 has mass number 12). - **Average Atomic Mass**: Weighted average of isot…
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21 what energy conversion occurs in a cars engine? thermal energy is co…
Chemical potential energy is converted into thermal energy.
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classify each of the following samples of matter as an element, compoun…
- Gasoline: Solution - Pizza: Mechanical Mixture - Copper Fillings: Element - A Cup of Coffee: Solution - Gold: Element - Baking Soda: Compound
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fossil fuels store chemical energy that can be converted to heat or ele…
TRUE
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the distance between the two hydrogen atoms in a molecule of water is 0…
A. \( 1.72 \times 10^{-10} \) m
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what previously known chemical did nobel use to make dynamite? a \tgunp…
b. nitroglycerine
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how can some types of batteries be recharged? a the chemicals in the ba…
c. Electrical energy reverses the chemical reactions in the battery.
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chemical reactions: a always release energy b always absorb energy c ca…
c. can either absorb or release energy
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determine the answer for the equation below with correct number of sign…
A. 2.1 ### Second Question (2.02 + 8.102 - 0.0297)
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true or false – circle one 6. polar molecules have a positive and negat…
True ### Question 7:
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what is rapidly produced during the burning process of gasoline that ul…
a. heat
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when gathering glassware and equipment for an experiment, you should ○ …
D. All of the above
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the correct number of significant figures in the number 1.250100 is: ○ …
7 (corresponding to the option "7") ### Second Question (Rounding 4.449 to two significant figures)
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some hand-warmers contain chemicals that undergo chemical reactions to …
heat
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15. what role does atomic size play in metallic bonding? a. larger atom…
a. Larger atomic size facilitates the movement of electrons among atoms.
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energy is released when we burn natural gas.
Thermal (or Chemical, depending on context; "Thermal" is the energy released, "Chemical" is the energy converted) (Note: If the question is simply to identify the type of energy r…
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13. which statement is true about bond strengths in resonance structure…
a. They are stronger than single bonds but weaker than double bonds.
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you are heating a substance in a test tube. always point the open end o…
D. away from all people
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what type of energy is released by the chemicals in a hand-warmer? a ki…
d. thermal energy
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after completing an experiment, all chemical wastes should be left at y…
B. disposed of according to your instructor's directions
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approved eye protection devices (such as goggles) are worn in the labor…
D. any time chemicals, heat or glassware are used
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if a laboratory fire erupts, immediately ○ notify your instructor ○ run…
A. notify your instructor
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flammable materials, like alcohol, should never be dispensed or used ne…
B. an open flame
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question 17 exercises - entrepreneurship: going from an idea to a busin…
A) marketing plan, management plan, and financial plan
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2. which bond length is likely to be observed in a resonance hybrid? a.…
d. A bond length between that of a single and a double bond.
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1. complete the table (table columns: element name, element symbol, ato…
s: a) Physical property b) Chemical property c) Physical property d) Physical property e) Physical property f) Chemical property g) Chemical property h) Physical property
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#3 chemistry a schoology 2025 7. draw and label the protons, neutrons, …
- Hydrogen - 1: Protons = 1, Neutrons = 0, Electrons = 1 - Hydrogen - 2: Protons = 1, Neutrons = 1, Electrons = 1 - Hydrogen - 3: Protons = 1, Neutrons = 2, Electrons = 1 (For dra…
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question 2 when comparing three oxidizing agents, nitric acid, cr⁺⁶ and…
D. Hydrogen peroxide is the "greenest" because it produces innocuous by - products
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when a lead nitrate solution is poured into a potassium iodide solution…
d. $\ce{Pb(NO_{3})_{2} + 2 KI -> PbI_{2} + 2 KNO_{3}}$
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the distance between the two hydrogen atoms in a molecule of water is 0…
B. \( 1.72 \times 10^{-10}\) m
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okay! everyone remember the buddy system! field trip today! which examp…
D. Often times only 1 sock is in the clean clothes basket after washing.
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offerings pizza—it is referred to as flatbread and is made with organic…
A) angel investors or venture capitalists.
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5. describe the process of freezing in terms of molecular motion and te…
Freezing is molecules losing kinetic energy, temperature decreases, forming structures. ### Question 6
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6. in gatorade, there is sodium and potassium. they are both ions with …
c. Electrolytes
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the correct number of significant figures in the number 0.027000 is: ○ …
The correct option is the one with 5 (the option that was marked, likely the second option with the text "5" as per the given choices).
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3. both boiling and evaporation are processes where a liquid changes in…
Boiling is specific temperature given pressure, evaporation is ranges of temperatures. ### Question 4
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how many significant figures are in the number 0.0107 possible points: …
The correct option is: A. three (assuming the option with "three" is labeled as A, if the original options have labels like A, B, C, D, we need to use the correct label. Since in …
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which of the following is an example of a substance with high viscosity…
B. road tar (assuming the options are labeled as A. alcohol, B. road tar, C. water, D. soda pop)
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a. breaking an ice cube b. melting gold c. running an electric current …
d. The total mass of the reactants equals the total mass of the products. ### Question 50
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43. which of the following is a chemical property of water at 4 degrees…
a. Its ability to decompose into hydrogen and oxygen ### Question 44
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what previously known chemical did nobel use to make dynamite? a toluen…
b. nitroglycerine
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37. what must occur for a change to be a chemical reaction? a. there mu…
b. There must be a change in chemical properties. ### Question 38
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what is schema? text plan prior knowledge action
C. prior knowledge (assuming the options are labeled A: text, B: plan, C: prior knowledge, D: action; if labels differ, adjust to the correct label with "prior knowledge")
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why does ice float when it is placed in liquid water? because ice is mu…
because the density of ice is less than water
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32. physical properties of matter include all of the following except. …
d. It's taste ### Question 33
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which branch studies energy and reaction rates? ○ analytical ○ physical…
B. Physical Chemistry
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bronze, a metal alloy mastered by shang dynasty smiths, had an advantag…
C. it was harder and stronger than copper
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27. a liquid is poured from a narrow container to a wide container. the…
b. shape ### Question 28
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a. a solution of two solids b. a mixture of particles with different de…
b. As the egg cooks, a new type of matter forms.
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6. what is an isotope? give an example.
An isotope is a variant of an element with the same atomic number (same number of protons) but different atomic mass (different number of neutrons). Example: Carbon - 12 ($^{12}\t…