化学
化学反应、化学计量、分子结构与元素性质。
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which of the following statements about the properties of elements rela…
- An atomic emission spectrum shows the pattern formed when light emitted by an element is separated into its different component wavelengths. - The light that an element emits is…
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storyline 1 exam 47 of 73 copper is a metal and has a cu2+ ion that rea…
The ratio of copper to bromine is \(1:2\)
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in this performance task, you will answer 4 questions. the united natio…
Nh
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storyline 1 exam which of the following statements about metals are tru…
- Metals in solid form have specific crystal structures. - Metals can be hammered into different shapes. - Metals can be drawn into wires.
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storyline 1 exam an atom of bromine has 35 electrons. these electrons a…
2, 8, 18, 7
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a chemistry graduate student is very skilled at analyzing atomic emissi…
Copper
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storyline 1 exam which of the following is a characteristic of the grou…
They have 4 valence electrons
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storyline 1 exam 36 of 73 which of the following statements about the s…
- The actual attraction felt by the electrons farthest from the nucleus is less than the numerical value based on Coulomb's law. - The effective nuclear charge \(Z_{eff}\) is defi…
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storyline 1 exam how many valence electrons are lost by the metallic el…
2
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storyline 1 exam write the name of the element with the electron config…
carbon
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chemistry students are learning about lewis structures. their instructo…
I. \(:\ddot{O}::C::\ddot{O}:\) III. \(:\ddot{O}=C=\ddot{O}:\)
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complete the rhyme scheme. a b b c c sometimes the mist overhangs my pa…
Line1: A, Line2: B, Line3: B, Line4: C, Line5: C
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read the passage and answer the next two questions. during a classroom …
It has two valence electrons; It belongs to the third period.
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storyline 1 exam bcl₃ is the product of boron and chlorine atoms. what …
boron trichloride
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read the passage and use the diagram to answer the next two questions. …
one; seven
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in this performance task you will answer four questions. the electron c…
halogens
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storyline 1 exam which of the following lewis structures correctly repr…
\(\ce{:Cl^{-}: Ca^{2+} :Cl^{-}:}\) (the second option)
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in this performance task, you will answer 4 questions. the united natio…
It would most likely form cations when it reacts.
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these three figures show that in a game of tug - of - war, the knot in …
The statement is correct. In Figure B, the balanced pull (analogous to equal electron - pulling by atoms with similar electronegativities in a non - polar covalent bond) indicates…
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review each of the chemical compounds and classify each one based on wh…
| Covalent | Ionic | |--|--| | \(CF_{4}\), \(NI_{3}\), \(C_{5}H_{10}O_{5}\) | \(K_{2}O\), \(NH_{4}Br\), \(Ba(OH)_{2}\) |
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how are the elements in todays modern periodic table arranged? in order…
in order of increasing atomic number
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in this performance task, you will answer 4 questions. the united natio…
have seven shells of electrons
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storyline 1 exam select the answer that shows the words in the correct …
electrons; valence
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which of the following statements about electron affinity are true? sel…
An atom with a higher electron affinity will release a greater amount of energy. Electron affinity is the energy change that occurs when an atom gains an electron. For the majorit…
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storyline 1 exam which arrangement of the following period 5 elements, …
Te, Sb, In, Sr, Rb
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storyline 1 exam a mystery element has 18 protons. which one of the fol…
The element belongs in row 3 of the periodic table and is classified as a noble gas.
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read the passage and use the diagram to answer the next two questions. …
Se, Na, Na, Ar, O
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storyline 1 exam select the statement that accurately explains why an a…
There are more positively charged subatomic particles in the atom’s nucleus.
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storyline 1 exam how can a scientist determine the strength of the inte…
by determining and comparing the electronegativity of the atoms in the compound, by identifying the shape of the molecule based on the number of covalent bonds that it forms, by h…
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storyline 1 exam select all the statements that best describe an atom. …
- is the smallest particle of an element that retains its identity in a chemical reaction - has no net charge and has a cloud surrounding a dense inner core - contains subatomic p…
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the list identifies various properties of four elements: element 1 is a…
Elements 2 and 4
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storyline 1 exam a calcium ion is formed from a calcium atom. how do th…
The calcium ion is smaller than the calcium atom because the same number of protons now attract a fewer number of electrons.
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the table shows the first, second, and third ionization energies of fou…
\(1,2,3\)
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oxygen reacts with many different elements to form different molecules.…
\(\text{CO (g)}\), \(\text{NO (g)}\)
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storyline 1 exam which list arranges the elements na, li, k, rb, and cs…
Cs, Rb, K, Na, Li
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storyline 1 exam which of the following formulas represent an ionic com…
\(\text{MgF}_{2}\), \(\text{BeS}\)
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storyline 1 exam name two elements that have similar properties based o…
Na and Li
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storyline 1 exam which characteristic is not a periodic trend? electron…
number of elements in a group
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1. which will not cause a safety hazard for individuals? cluttered path…
1. Chemicals in locked room 2. The individual's care plan 3. TRUE 4. Create a culture of safety.
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this image shows someone practicing good hygiene. what does this hygien…
the transmission of disease
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write the empirical formula for at least four ionic compounds that coul…
\(Fe(ClO_{3})_{3}\), \(Fe_{2}(CO_{3})_{3}\), \(Pb(ClO_{3})_{4}\), \(Pb(CO_{3})_{2}\)
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what is the average daily amount of a nutrient that will maintain a spe…
c. Estimated Average Requirement (EAR)
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write the empirical formula for at least four ionic compounds that coul…
\(Pb(NO_{3})_{4}\), \(Pb(IO_{3})_{4}\), \(Fe(NO_{3})_{3}\), \(Fe(IO_{3})_{3}\)
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24 eight - month - old gina finds that when she pulls on the cord at th…
24. B. secondary circular reactions 25. B. coordination of secondary schemes
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question 21 emma loves to place her cheek on the window because she lik…
Question 21: C. circular reaction Question 22: D. primary circular reaction Question 23: B. secondary circular reactions
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write the empirical formula for at least four ionic compounds that coul…
\(Fe_{3}(PO_{4})_{2}\), \(Fe(IO_{3})_{2}\), \(FePO_{4}\), \(Fe(IO_{3})_{3}\)
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utility operation and distribution use the information below to answer …
to ensure the purity and safety of drinking water
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are categories formed within memory (round items under roundness, etc.)…
- First Question: Schemas - Matching: - New material gets in the way of old or vice versa: Interference - Unable to locate the memory later: Amnesia - New learning distorts old me…
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which type of memory has the following characteristics: the information…
1. Sensory Memory 2. Short - Term Memory 3. Schemas
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according to the rule of 8, what happens to sodium and chlorine atoms w…
Sodium loses an electron, chlorine gains one.
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select all groups that will gain electrons when becoming an ion:
Groups 15 (5A), 16 (6A), 17 (7A)
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what is condensation? the process from which a solid turns into a liqui…
For the first question: the process from which a gas turns into a liquid. For the second question: solid and liquid.
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how do the molecules move in a liquid? o they are not far but close and…
First question: they are close together and move faster Second question: solid
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what happens to the molecules when heat is applied? they move slower an…
For the first question: they move faster and further away. For the second question: It increases because the molecules are moving away from each other.
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what happens to the molecules when heat is applied? they move slower an…
For the first question: they move faster and further away. For the second question: It increases because the molecules are moving away from each other.
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select the correct answer. what is the greatest difference between ben …
B. tone
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question 273 chemical reactions which species is the conjugate acid in …
\(H_3BO_3\)
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which element has 7 protons? * 2 poin periodic table of the elements ni…
Nitrogen (N)
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which element has 26 protons? * 2 points calcium (ca) nitrogen (n) neon…
Iron (Fe)
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which element has 55 protons? * 2 points periodic table of the elements…
Caesium (Cs)
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which element has 10 protons? * periodic table of the elements neon (ne…
Neon (Ne)
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which element is a noble gas? * 2 points periods groups carbon (c) kryp…
Krypton (Kr)
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what element has an atomic number of 1?* 2 points periodic table of the…
Chlorine (Cl)
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which element has 36 protons? * 2 points periodic table of the elements…
Krypton (Kr)
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which element has 47 protons?* 2 points nickel (ni) copper (cu) zinc (z…
Silver (Ag)
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which element has an atomic number of 6? * 2 points fluorine (f) nitrog…
Carbon (C)
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what element has 2 protons? * periodic table of the elements manganese …
Helium (He)
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which element has 23 protons? * periodic table of the elements h li be …
Vanadium (V)
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102. ml of two different liquids are poured into uncovered identical be…
Evaporation rate
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which of the following are properties of covalent bonds? (check all tha…
Low melting and boiling points, Shared electrons between atoms, Poor conductivity in solid and liquid states.
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which of the following do you think would melt first, nacl (ionic bond)…
C₆H₁₂O₆
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how many bonds do each of the following make? carbon (c) nitrogen (n) o…
1. Carbon (C): 4 2. Nitrogen (N): 3 3. Oxygen (O): 2 4. Bromine (Br): 1
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physical science - power practice problems 1. if a runners power is 400…
\(240000\space J\) ### Problem 2
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extra credit the symbol for sodium doesnt seem to match the word \sodiu…
The word is Natron and is from Latin.
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when matter changes from a liquid to a solid, its particles lose energy…
TRUE
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which element is in period 3, group 18? * 2 points fluorine (f) neon (n…
Argon (Ar)
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a liquid freezes because its particles lose energy. true false
TRUE
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what element is in period 4, group 13? gallium (ga) indium (in) aluminu…
Gallium (Ga)
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analyze how each of the three actions in the table increases the kineti…
- Raise the temperature of the object: Increases kinetic energy (and total thermal energy). - Pull atoms or molecules that attract one another farther apart: Increases potential e…
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noah and nina are 15 m apart in a closed room. noah says the same sente…
The second sound wave reflects off the walls of the room, so Nina is able to hear the sound.
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a sound wave travels through air. in which regions are air molecules th…
D. rarefactions
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7. how many formula units are in 0.21 mol of magnesium nitrate, mg(no₃)…
7. \(1.3\times 10^{23}\) formula units. 8. \(3.36\times 10^{25}\) molecules. 9. \(1.5\times 10^{24}\) molecules.
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use the text to compare and contrast acids and bases. an acid is define…
- Have a pH less than 7.0: Acids - Taste sour: Acids - Are usually solids: Bases - Change litmus paper to red: Acids
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for thousands of years, humans have been eating fermented foods, or foo…
- Undergoes fermentation, or special chemical changes: Yogurt (✔), Sour cream (✔) - Frequently used in Middle Eastern dishes: Yogurt (✔), Sour cream (✖) - High in protein: Yogurt …
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the diagram below is a model of two solutions. each yellow ball represe…
Solution A
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the diagram below is a model of two solutions. each purple ball represe…
Solution B
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the diagram below is a model of two solutions. each pink ball represent…
Solution A
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the diagram below is a model of two solutions. each blue ball represent…
Solution A
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look at the model. then, choose the best answers. 5 choose the best ans…
5. 2 6. 3
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note: to answer some of the questions, it may help to reference a perio…
The release of energy through noise is a sign of a chemical reaction.
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re - order each list in the table below, if necessary, so that the atom…
\(Li,O,Ne\); \(I^{-},Br^{-},Cl^{-}\); \(Se^{2-},Se,Kr\)
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use the dot structure on the right and the periodic table to determine …
potassium (K)
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use the electron configurations and the periodic table to answer the qu…
nitrogen (\(N\))
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consider a hypothetical chemical reaction: $a + b \\to c + d$ (in this …
- What is the heat of reaction? $250\ \text{kJ/mol}$ - Is the reaction exothermic or endothermic? Endothermic - Can you determine the activation energy? Yes, it's $300\ \text{kJ/m…
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multiply or divide the following measurements. be sure each answer you …
\(7.8\times10^{2}\frac{\text{g}}{\text{mL}}\), \(7.3183\frac{\text{g}}{\text{mL}}\), \(9.4\times 10^{2}\text{cm}^{2}\)
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use the references to access important values if needed for this questi…
The coefficients: \(Sb_2O_5 = 1\), \(Mn = 2\), \(SbO^+=2\), \(Mn^{2+}=2\) Water appears as a product with a coefficient of \(1\) The reducing agent is \(Mn\)
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identify the species oxidized, the species reduced, the oxidizing agent…
species oxidized: \(Al\) species reduced: \(Mn^{2+}\) oxidizing agent: \(Mn^{2+}\) reducing agent: \(Al\) Electrons are transferred from \(Al\) to \(Mn^{2+}\)
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excerpt from is it a crime for a u.s. citizen to vote? by susan b. anth…
She uses logic to explain why women's suffrage should not actually be illegal.
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endothermic vs exothermic chemical reactions involve changes in _. rega…
- **Endothermic reaction blanks**: absorbs, break, heat, down - **Exothermic reaction blanks**: releases, form, heat, up
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1. what is the main difference between a physical and chemical change? …
1. A. Physical changes alter the appearance but not the composition, while chemical changes create new substances 2. C. Baking a cake 3. D. Formation of a gas, color change, tempe…