化學
化學反應、化學計量、分子結構與元素性質。
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question 3 1 pts the complete ionic reaction for the balanced equation …
\(3Ca^{2 +}(aq)+6NO_3^{-}(aq)+6Na^{+}(aq)+2PO_4^{3 -}(aq)\to Ca_3(PO_4)_2(s)+6NO_3^{-}(aq)+6Na^{+}(aq)\) (the first option)
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question 29 1 pts calculate the standard enthalpy change for the format…
181
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the spectator ions in the reaction shown are 2 agno₃ (aq) + k₂so₄ (aq) …
potassium ion and nitrate ion. ### Question 2
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question 10 1 pts which of the following equations is not balanced? 2 a…
\(C_7H_{16}+10O_2 ightarrow7CO_2+8H_2O\)
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question 8 1 pts when the reaction shown is correctly balanced, the coe…
Question 8: \(1,1,1,2\) (the fourth option) Question 9: \(3Ca(NO_3)_2(aq)+2Na_3PO_4(aq)\to Ca_3(PO_4)_2(s)+6NaNO_3(aq)\) (the second option)
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question 7 1 pts when the reaction shown is correctly balanced, the coe…
\(2,19,12,14\) (the fourth option)
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question 5 1 pts which of the following equations is not balanced? $c_{…
\(SO_2 + O_2 ightarrow SO_3\) ### Question 6
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question 3 1 pts which statement regarding balanced chemical equations …
The statement “Subscripts may be changed to make an equation simpler to balance” is not true. # Question 4 ## Step1: Balance the oxygen atoms The un - balanced equation is \(KClO_…
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question 1 1 pts in a chemical reaction there are equal numbers of mole…
the number of atoms on each side of the reaction arrow. # Question 2
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question 14 1 pts are present on both the reactant and product side of …
- Question 14: Spectator ions - Question 15: net ionic
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question 12 1 pts a balanced equation where the reactants and products …
Question 12: B. molecular Question 13: C. complete ionic
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which is the electron configuration for zinc? 1s²2s²2p⁶3s²3p⁶4s²3d⁸ 1s²…
\(1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}\) (the fourth option)
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question 11 1 pts match the physical states of reactants and products i…
solid - (s), liquid - (l), gas - (g), aqueous solution - (aq)
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question 9 1 pts to balance a chemical equation,__________are added ste…
Question 9: coefficients Question 10: whole number
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question 7 1 pts a balanced chemical equation means that______ of atoms…
A. equal numbers ### Question 8
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a chemical reaction is performed in a flask that is sealed with a pisto…
+101 J
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question 5 1 pts coefficients for a chemical reaction are usually repre…
whole - numbers ratios # Question 6
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a chemist is studying an unknown substance and could break the substanc…
pure substance
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question 3 1 pts substances undergoing reaction are called while the su…
Question 3: reactants, products Question 4: coefficients
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6. describe the structure of a typical atom. identify the location and …
A typical atom consists of a nucleus (center) with protons (+ charge) and neutrons (no charge), and electrons (- charge) orbiting the nucleus.
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en 1947, los británicos dividieron el subcontinente indio en india y. p…
Primera pregunta: Pakistán. Segunda pregunta: musulmanes y sijs.
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given the chemical name, identify the chemical formula hexafluorine hep…
\(F_6I_7\)
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given the chemical name, identify the chemical formula tetrabromine pen…
\(P_5Br_4\)
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what is the weakest and longest type of covalent bond? single bond ioni…
Single bond
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what is the name of this ionic compound? snco3 tin (ii) carbonate tin (…
tin (II) carbonate
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what is the name of this ionic compound? al(oh)3 aluminum oxohy dride a…
aluminum hydroxide
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what is the name of this ionic compound? k₂co₃ dipotassium carbontrioxi…
potassium carbonate
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what is the name of the ionic compound formed from these two components…
aluminum phosphate
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how many shared electrons are present in a triple bond? two four six ei…
Six
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the polyatomic ion in this compound is nitrate, no3-. what is the name …
zinc nitrate
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what is the name of the underlined polyatomic ion in this compound? zn(…
nitrate
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what should the shape of a molecule be that consists of one atom of a g…
Trigonal pyramidal
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what does vsepr theory stand for? valence-shell electron pair rotation …
Valence - Shell Electron Pair Repulsion
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what is a polyatomic ion? * a single atom with multiple charges a molec…
A group of covalently bonded atoms that behaves as an ion
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a represents both the identities and the relative quantities of substan…
1. B. chemical equation 2. A. carbon dioxide and water
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what is the shape of the ammonia molecule as predicted by vsepr theory?…
Pyramidal
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what affects the properties of covalent molecules? the charge of the io…
The arrangement of atoms in the molecule.
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calculate the standard enthalpy change for the reaction at 25°c. standa…
\(-2043.9\)
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what is the exception to the octet rule mentioned in the text? oxygen c…
Hydrogen
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the freezing point of water is 32° f. tim added potassium and found out…
\(24^{\circ}F\)
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question 21 explain, in your own words, why ionization energy and elect…
Ionization energy and electronegativity have a direct relationship because both depend on the effective nuclear charge. A higher effective nuclear charge (due to fewer electron sh…
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which risk factor is most likely to be encountered in a workplace? a. h…
C. Lack of safety equipment
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how is a pure substance different from a mixture? pure substances are s…
Mixtures are made up of more than one component.
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question 2 explain, in your own words, why ionization energy and electr…
Ionization energy and electronegativity have a direct relationship because both depend on the nuclear charge and atomic radius. A higher nuclear charge and smaller atomic radius (…
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which choice is a mixture? water sugar salad potassium
salad
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match each orbital with the maximum number of electrons it can hold. co…
1. a. 2 2. g. 6 3. f. 10 4. e. 14
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which choice is a compound? carbon dioxide air carbon oxygen
carbon dioxide
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which choice is an element? o potassium o sugar o salad o water
Potassium.
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match each orbital with the maximum number of electrons it can hold col…
2. S (Sulfur), 3. Al (Aluminum), 1. Ti (Titanium), 5. Zn (Zinc), 4. Rb (Rubidium)
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what is the formula for the ammonium ion? nh₄⁺ nh₃ am⁺ amo⁺
\(NH_4^+\)
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why can some mixtures not be classified as solutions? not all mixtures …
Not all mixtures are homogeneous.
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what is the name of this ion? h₃o⁺ water positive hydrate trihydrogen o…
hydronium
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valence electrons can be found via the periodic table by determining an…
B. Group
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what polyatomic ion is present in the following formula? kmno4 ammonia …
permanganate
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what is the formula for the hydroxide ion? ho+ h2o h2- oh-
$OH^{-}$
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rank the following from least electronegative to most: 1. ba 2. v 3. si…
Ba, V, Si, O
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rank the following in order of smallest atomic radius to largest 1. b 2…
B < Ga < Y < Cs
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what is the name of this ion? c₂h₃o₂⁻ acetate bicarbonate hydronium cya…
acetate
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what are polyatomic ions? what is the name for the cn⁻ ion? carbonitrat…
C. cyanide
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which statements describe iambic pentameter as it is used in shakespear…
- Each line contains five metrical feet. - In a group of two syllables, the second is stressed.
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what are polyatomic ions? what is the formula for the chlorate ion? cl-…
$\ce{ClO3-}$ (the third option)
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debrow, josiah chemistry jmbk 2025 - 26 sea ice provides a habitat for …
Ice floats on liquid water, because water is less dense as a solid.
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what are polyatomic ions? what is the name for the cro4^-2 ion? chromox…
chromate
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what are polyatomic lons? what is the formula for the permanganate ion?…
\(MnO_4^-\)
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rank the following from least metallic to most. 1. ti (titanium) 2. s (…
1. g. Group 1 2. a. Group 2 3. c. Groups 3 - 12 4. h. Group 17 5. b. Group 18
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question 7 elements in group ______ are known as the noble gases and th…
Question 7: Blank 1: 18 (or 8A) Blank 2: do not Question 8: Sr < Ag < Al < N
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question 9 the image shows the absorption spectrum for sodium (na) of t…
a. Line A # Question 10
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many vitamins come from a healthy diet and some are available as supple…
Water is a universal solvent.
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question 5 write the electron configuration for barium. you can use eit…
[Xe]6s(2)
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conservation of mass you and your friends plan a camping trip. to make …
No, the chemical equation \(C_3H_8 + O_2 ightarrow CO_2 + H_2O\) is not balanced. Because the number of carbon, hydrogen, and oxygen atoms on the reactant side (\(3\) C, \(8\) H, …
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conservation of mass in a closed system, a student combines vinegar and…
50 grams
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which of the following ions would result in an element having 8 valence…
a. \(Cl^-\), b. \(Sb^{3 - }\), c. \(Na^+\), e. \(Ca^{2+}\)
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question 1 true or false: elements in the same group have similar prope…
True
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acids & bases think about the ph scale. the numbers listed below are th…
lemon juice - 2.5, vinegar - 4.0, soft drink - 2.9, tomato juice - 5.1, ketchup - 3.8, unknown solution - 1.3
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question 17 as atomic radii decreases, electronegativity and ionization…
Blank 1: increases Blank 2: increases
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acids & bases think about the ph scale. the numbers listed below are th…
Ammonia - 11.6, Eggs - 7.8, Baking soda solution - 8.5
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how do hydrogen bonds in water affect its characteristics? select all c…
It gives water its cohesive properties. The bonds help create surface tension in bodies of water. Polar molecules like salt and sugar dissolve easily.
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what do aluminum (al), sodium (na), and chlorine (cl) have in common? t…
They are all in the same period.
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which reaction involves elements from group 2 and group 16? h2 + cl2 → …
\(2Ca + O_2 ightarrow2CaO\)
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why are the blueberry and strawberry pancakes considered a heterogeneou…
because each bite can contain a different combination of ingredients
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the substances that make up water are h and o. what type of substances …
elements
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what defines a pure substance? a combination of various elements and co…
B. A substance made of the same type of atom, such as elements on the Periodic Table.
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name formula ammonium nh₄⁺ hydronium h₃o⁺ hydroxide oh⁻ nitrate no₃⁻ ni…
acetate
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common polyatomic ions use your polyatomic ion list to complete the tab…
\(NO_{2}^{-}\) (corresponding to the middle option \(NO_{2}^{-}\) among the given choices)
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common polyatomic ions use your polyatomic ion list to complete the tab…
OH⁻
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common polyatomic lons use your polyatomic ion list to complete the tab…
hydronium
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common polyatomic ions use your polyatomic ion list to complete the tab…
\(NH_4^+\)
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when 0.815 g of sodium metal is added to an excess of hydrochloric acid…
\(-479\space kJ\)
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q29. (7 points) (a) add the coefficients to balance the following chemi…
\(1C_3H_8(g)+5O_2(g)\to3CO_2(g)+4H_2O(l)\) ### (b) From the balanced equation \(C_3H_8(g)+5O_2(g)\to3CO_2(g)+4H_2O(l)\), the mole ratio of \(C_3H_8\) to \(CO_2\) is \(1:3\).
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q28. (2 points) show calculation for the number of fluoride ions (f-) i…
\(6.50\times 10^{24}\) fluoride ions.
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when a 2.00 g sample of rbbr is dissolved in water in a calorimeter tha…
\(21.9\space kJ/mol\)
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how do the properties of metalloids compare to the properties of metals…
Some of their properties are the same
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what other two properties do metals have? choose two answers. malleable…
malleable (they can be flattened into sheets), ductile (they can be pulled into wires)
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what is the formula of the ionic compound iron (iii) fluoride? fe₃f₃ fe…
B. \(FeF_{3}\)
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what is the name of the ionic compound cose? cobalt (ii) selenide coppe…
cobalt (II) selenide
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what is the name of the ionic compound $znbr_{2}$? zinc(i) bromide zinc…
zinc bromide
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which of the following elements does not form more than one ion? au pb …
Zn
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what is the charge on the lead in lead(iv) iodide? -4 +4 -1 +2
B. +4
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mixture diagrams label the diagrams as homogeneous or heterogeneous. 1.…
1. Homogeneous 2. Homogeneous 3. Heterogeneous 4. Heterogeneous 5. Homogeneous 6. Heterogeneous 7. Heterogeneous 8. Heterogeneous 9. Heterogeneous 10. Homogeneous 11. Homogeneous …
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what is the name of tio2, where the titanium has a charge of +4? titani…
titanium(IV) oxide