化学
化学反応、化学量論、分子構造、元素の性質。
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12. choose the best answer. what is this reaction classified as? $2na_3…
11. gas 12. double replacement
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choose the best answer. what type of single replacement reaction is tak…
D. the replacement of hydrogen in an acid by a metal --- ### For Question 10:
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on a 14 day wilderness expedition youll need to heat 3.0 kg of water to…
3
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4. choose all that apply. which two skeleton or balanced equations repr…
## Question 4: C. $3\text{H}_2(g) + \text{N}_2(g) ightarrow 2\text{NH}_3(g)$ D. $\text{KCl} + \text{O}_2 ightarrow \text{KClO}_3$ ## Question 5: precipitate, water ## Question 6: …
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1 choose the best answer. which equation shows that heat has been added…
1. $\text{H}_2\text{O} \xrightarrow{\Delta} \text{H}_2 + \text{O}_2$ 2. synthesis 3. $\text{N}_2(g) + \text{O}_2(g) + \text{H}_2\text{O}(g)$
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name _______________________________ due friday, january 25, 2026 celeb…
### Hotest Container (Gas, assuming thermal energy increases up) #### Sketch: Draw particles (molecules/atoms) far apart, moving freely and randomly (including translational, rota…
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3) choose the best answer. look at the products of this equation. what …
3) A. gas 4) B. precipitate, C. water 5) A. $2\text{HCl} + \text{CaCO}_3 ightarrow \text{CaCl}_2 + \text{H}_2\text{O} + \text{CO}_2$
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6) choose the best answer. the yellow substance in the test tube shown …
(Question 6): precipitate ---
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4. how many moles are present in 120 g of caco₃? 5. calculate the mass …
1.2 moles ### Question 5
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thinking steps: 1. write the unbalanced chemical equation with the corr…
1. $\boldsymbol{2}\ce{H_2} + \boldsymbol{1}\ce{O_2} ightarrow \boldsymbol{2}\ce{H_2O}$ 2. $\boldsymbol{1}\ce{N_2} + \boldsymbol{3}\ce{H_2} ightarrow \boldsymbol{2}\ce{NH_3}$ 3. $\…
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4) drag and drop the equations with the descriptions. 2al(s) + 3cucl₂(a…
### Drag-and-Drop Matches: 1. $2\text{Al}(s) + 3\text{CuCl}_2(aq) ightarrow 2\text{AlCl}_3(aq) + 3\text{Cu}(g)$ → the replacement of a metal cation by another metal 2. $2\text{Li}…
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2) choose the best answer. identify the two cations that swap in the fo…
1. reactive series 2. $\text{Ag}^{+}$, $\text{H}^{+}$
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how many atoms are indicated by the prefixes for each of the following …
- 1 atom: monochloride - 2 atoms: difluoride, dibromide - 3 atoms: trifluoride, trioxide - 4 atoms: tetrasulfide, tetrabromide - 5 atoms: pentachloride - 6 atoms: hexabromide
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drag the labels to their respective targets. view available hint(s) res…
### Part A (Matching Chemical Formulas to Covalent Compounds) # Explanation: ## Step 1: Analyze Phosphorus Trichloride Phosphorus trichloride has one phosphorus (P) and three chlo…
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part a determine whether the name shown for each of the following molec…
- Correct: \( \boldsymbol{\ce{NF_3}} \) (nitrogen trifluoride) - Incorrect: \( \boldsymbol{\ce{PBr_5}} \) (phosphorus(V) pentabromide), \( \boldsymbol{\ce{P_2O_3}} \) (phosphorus …
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part a determine whether the name shown for each of the following molec…
To solve this, we analyze each compound's naming using molecular compound nomenclature (prefixes for non - metal - non - metal compounds, and for some with variable oxidation stat…
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missed this? watch kcv: names: molecular compounds, iwe: nomenclature: …
correct: \( \boldsymbol{SCl_4} \) (sulfur tetrachloride) incorrect: \( \boldsymbol{CCl_4} \) (carbon (IV) iodide), \( \boldsymbol{CO} \) (carbon oxide), \( \boldsymbol{NCl_3} \) (…
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learning goal: to learn how to write ionic formulas. here are some thin…
\( \text{CuO} \) ### Part B
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a hand warmer packet contains iron powder (fe) that reacts with oxygen …
The molar mass of $\ce{Fe_{2}O_{3}}$ is approximately $159.7\space g/mol$. ### Second Sub - Question: Compare the molar mass of $\ce{Fe_{2}O_{3}}$ to the molar mass of $\ce{O_{2}}…
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a hand warmer packet contains iron powder (fe) that reacts with oxygen …
- Molar mass of $\ce{Fe_{2}O_{3}}$: $\boldsymbol{159.7\ \text{g/mol}}$ (or approximately $160\ \text{g/mol}$) - $\ce{Fe_{2}O_{3}}$ is heavier. The molar mass of $\ce{Fe_{2}O_{3}}$…
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density table (partially visible) with liquids and their densities in g…
Density: $0.93\ \text{g/cm}^3$ Is it possible to identify the liquid? $\bigcirc$ yes Identified liquid: pentane
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liquid | density carbon tetrachloride | \\(\\frac{1.6\\ \\text{g}}{\\te…
Calculated density: $\boldsymbol{0.79\ \text{g/mL}}$ Is it possible to identify the liquid? $\boldsymbol{\text{yes}}$ Identified liquid: $\boldsymbol{\text{acetone}}$
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first, launch the video below. during the video, youll be asked a conce…
D. All of the statements identify why the formula - name is wrong.
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first, launch the nomenclature interactive. during the interactive, you…
B. aluminum bromide ### Part B
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missed this? watch iwe: writing formulas for ionic compounds containing…
$\boldsymbol{NaClO_2}$ (corresponding to the option "NaClO₂")
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missed this? watch iwe: writing formulas for ionic compounds; read sect…
A. \( \boldsymbol{BaBr_2} \)
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when a metal and a nonmetal exchange electrons to make a cation and an …
Form ionic bonds: manganese and chlorine, chlorine and sodium, sulfur and calcium, potassium and sulfur Do not form ionic bonds: nitrogen and bromine, lithium and calcium ### Part…
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some metals can form ions of different charges in different compounds. …
3+ (corresponding to the option "3+")
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what are the group numbers of these metals? drag the appropriate elemen…
- Group 1A: Li, Na, K, Rb, Cs - Group 2A: Ba, Ca, Sr, Mg - Group 3A: Al - Group 4A: (No elements)
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part a select the metals that form only one type of ion (that is, metal…
A. Sr, B. Al, C. Li, D. K, E. Cs, F. Mg, G. Ca, H. Na, I. Rb, J. Ba
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what questions do you need to ask about a substance in order to determi…
- An atomic element: Does it have single atoms as its base units? - An ionic compound: Is it composed of a metal cation and a nonmetal anion? - A molecular compound: Is it compose…
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classify each of the following compounds as ionic or molecular. if a co…
- Molecular: \( \text{NO}_2 \), \( \text{CBr}_4 \) - Ionic, one type of ion: \( \text{KCl} \) - Ionic, more than one type of ion: \( \text{Sn(SO}_4\text{)}_2 \)
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periodic table what is the density of carbon monoxide gas at stp condit…
A. 1.25 g/L
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what was silicon valley named after? (1 point) elements studied in chem…
○ chips used in computers
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how many moles of helium would you find in a birthday balloon that had …
A. 0.28 moles
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click on each blank box and select the option that completes the senten…
L/mol
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a teacher has given a lab student a white chemical sample and asks her …
46.7
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a reaction requires 2.573 moles of zinc oxide. how many grams of zno ar…
C. 209.5 g
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write the equilibrium constant expression for this reaction: h₂so₄(aq) …
\( K=\frac{[\ce{H+}]^2[\ce{SO4^{2-}}]}{[\ce{H2SO4}]} \)
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question 20 for the first reaction: (\boldsymbol{\text{maroon molecule}…
yes ### Second Equilibrium (Gray ⇌ Purple, \( K = \frac{1}{5} \))
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that is, select 1 in the second column for the most acidic molecule, 2 …
(Example Selection) - Bottom molecule: Select $\boldsymbol{1}$ (most acidic). - Third molecule: Select $\boldsymbol{2}$. - Top molecule: Select $\boldsymbol{3}$. - Second molecule…
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question 8 12.5 pts why is an acid - base indicator used in the experim…
The correct option is the one stating "It provides evidence that protonated water is being produced." (The option with the text "It provides evidence that protonated water is bein…
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question 5 which of the following is not a piece of equipment used in t…
C. a spectrophotometer ### Question 6
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12.3 participles and participial phrases key information participles ar…
### Part A: Identifying Participles and Participial Phrases 1. **Sentence**: Standing on the corner of Hollywood and Vine, Barbara felt as if she owned the world. - Participle/Par…
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answer the questions in the table below about the shape of the iodine p…
(First Question): 6 ### Second Question (Arrangement of Electron Groups)
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check the box under each compound that exists as a pair of cis/trans is…
The box under the compound \(Cl - C(CH_3)=C(Cl)-CH_3\) (the second compound in the table) should be checked.
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the temperature at which the following process reaches equilibrium at 1…
144°C (corresponding to the option: 144°C)
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the heat of fusion $\\delta h_f$ of butane $c_4h_{10}$ is 4.7 kj/mol. c…
-1.3 J/K
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for a chemical reaction, given $delta h^{circ} < 0$ and $delta s^{circ}…
As temperature increases, $\Delta G^\circ$ decreases. (The option with this statement)
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here are sketches of four atomic electron orbitals: a b c d are any of …
### Part 1: Are any of them s orbitals? s orbitals have a spherical shape. Orbitals A and C are spherical, so the answer is "yes". ### Part 2: List the s orbitals, if any. From th…
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what is $\\delta g^\\circ_{\\text{rxn}}$ in kj/mol for this reaction at…
-3497
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what is $\\delta g^\\circ_{\\text{rxn}}$ for the combustion of propane …
-2073.1 kJ/mol (corresponding to the option: -2073.1 kJ/mol)
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what is $\\delta g^\\circ_{\\text{rxn}}$ for the combustion of propane …
$\boldsymbol{-2073.1\ \text{kJ/mol}}$ (corresponding to the option: -2073.1 kJ/mol)
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this lewis structure may be incomplete. formal charges and bonds are sh…
Add one lone pair (two dots) to the oxygen atom. The carbon and hydrogen atoms have no missing lone pairs. So the Lewis structure should have a lone pair on the oxygen.
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which of these structures shows how the pictured molecule will look aft…
The structure in the second box (the one with Br as a wedge on the left - most carbon of the central two - carbon Br - containing part and a dashed Br below, with the double bond …
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13. another way to describe the slope is to use a for every statement. …
55.8 (the option with 55.8)
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12. analyze the graph to find the slope of the line for element 2. iden…
Slope of Element 2 = 207 \(\frac{g}{mol}\)
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8. another way to describe the slope is to use a for every statement. i…
12.0 (from the choices: the option with "12.0" as the value, so the choice is the one labeled 12.0, e.g., if the choices are listed as options, the correct one is the one with 12.…
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7. analyze the graph statistics to find the slope of the line for eleme…
Slope of Element 1 $=\boldsymbol{55.8}\frac{\boldsymbol{\text{g}}}{\boldsymbol{\text{mol}}}$
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identify the for every statement that matches the slope for element 2. …
65.4
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12. convert the following using dimensional analysis. show all work, in…
a) $0.001125\ \text{L}$ b) $8.5 \times 10^{-18}\ \text{Mg}$ c) $\approx 38580\ \text{lb/m}^3$ d) $1263.6\ \text{km/hr}$ e) $\approx 1.495 \times 10^6\ \text{in}^3$ f) $256.15\ \te…
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answer the questions below about the highlighted atom in this lewis str…
s: - Sigma bonds: \(\boldsymbol{2}\) - Pi bonds: \(\boldsymbol{2}\) - Hybridization: \(\boldsymbol{sp}\)
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write the systematic name of each organic molecule: | structure | name …
First: 2,3,5 - trimethylheptane Second: 4 - ethyl - 3 - methylheptane Third: 4 - chloro - 6 - methylheptane
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arrange the highlighted bonds in the table below in decreasing order of…
- For the \( \text{C-F} \) bond (first row): 1 - For the \( \text{C-O} \) bond (second row): 2 - For the \( \text{C-C} \) bond (third row): 3
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provide the correct name for nahco₃
Sodium bicarbonate (or Sodium hydrogen carbonate)
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what does a - z represent in nuclide symbol? \\(_{z}^{a}x\\) \\(\\bigci…
### First Question (What does A - Z represent in nuclide symbol?): # Brief Explanations: In the nuclide symbol \(\ce{_Z^A X}\), \(A\) is the mass number (number of protons + neutr…
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the two half-reactions are given below. \\( 3\\text{e}^- + 4\\text{h}_2…
The coefficient of \(H_2O\) in the balanced net ionic equation is 8.
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the redox reaction given below occurs in basic solution.\\(\\ce{tco^-_{…
2
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the redox reaction given below occurs in basic solution. tco₄⁻ + sn⁺² →…
3
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the electrons are on the reactant side. how many electrons are needed t…
\(6\)
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the bromate reacts with iron(ii) ions, forming bromide ions and iron(ii…
A. $\ce{BrO^{-}_{3}}$
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3.0 m hydrochloric acid is poured over an iron nail and a reaction happ…
A. Chloride ion becomes chlorine gas.
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what is the balanced chemical reaction occurring when zinc metal is add…
$\ce{Zn + 2HF -> ZnF2 + H2}$ (the option: $\boldsymbol{\ce{Zn + 2HF -> ZnF2 + H2}}$)
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2nh₄oh + 1kal(so₄)₂ + h₂o → 2al(oh) + (nh₄)₂so₄ + koh +
# Explanation: ## Step1: Identify reactants and products Reactants: \(2\text{NH}_4\text{OH}\), \(\text{KAl(SO}_4\text{)}_2\), \(\text{H}_2\text{O}\) Products: \(\text{Al(OH)}_3\),…
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i need a hint 7.89×10²⁴ molecules h₂o × (a units / c units) = choices: …
The value of A is \(1\) (mole) and the value of C is \(6.02\times 10^{23}\) (molecules \(H_2O\)). So in the given format, A is \(1\) and C is \(6.02\times 10^{23}\). If we conside…
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use a system of equations to solve this problem. a chemist currently ha…
7.5 L of 5% solution 2.5 L of 25% solution
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8.77 moles × (6.022 × 10²³ sodium ions) / 1 mole =
\(5.28\times10^{24}\) (or \(5.281394\times10^{24}\)) sodium ions (the answer can be rounded to an appropriate number of significant figures, here 8.77 has three significant figure…
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34.29 ml of 0.15 m hbr reacts with a 0.20 m solution of methylamine. wh…
\(25.72\)
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the weak base methylamine, ch₃nh₂, is used in the production of insecti…
1
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patrick makes his solution and standardizes it using khp (204.22 g/mol)…
0.110 (or more precisely, after detailed calculation: $\frac{0.7863}{204.22\times0.03510} \approx 0.110\ M$)
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patrick needs to make 100. ml of 0.15 m naoh in order to conduct an exp…
0.60
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what is the purpose of an indicator in a titration experiment? to deter…
A. to determine the end point
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what is the end point in a titration? the point where the indicator cha…
A. The point where the indicator changes color.
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what volume of 1.25 m hcl reacts with 13.49 g al in the reaction below?…
1.2
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what volume, in ml, of 0.35 m ca(no₃)₂ is required to completely react …
\( 107 \) (or more precisely, using exact calculation: \( \frac{0.75 \times 50.0}{0.35} \approx 107.14 \), rounded to appropriate sig figs, 107 mL)
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a container holds 1.0 l of 0.5 m alcl₃ solution. how many moles of al³⁺…
0.5 moles \( \text{Al}^{3+} \) (corresponding to the option: 0.5 moles \( \text{Al}^{3+} \))
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a container holds 1.0 l of 0.5 m alcl₃ solution. how many moles of cl⁻ …
1.5 moles Cl⁻
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which equation describes the dissociation of alcl₃ as it dissolves in w…
A. \( \text{AlCl}_3 ightarrow \text{Al}^{3+} + 3\text{Cl}^- \)
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a container holds 2.0 l of 2.0 m na₂co₃ solution. how many moles of co₃…
4.0 moles \( \text{CO}_3^{2-} \) (the first option: 4.0 moles \( \text{CO}_3^{2-} \))
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a container holds 2.0 l of 2.0 m na₂co₃ solution. how many moles of na⁺…
8.0 moles \( Na^+ \) (the first option: 8.0 moles \( Na^+ \))
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which equation describes the dissociation of na₂co₃ as it dissolves in …
A. $\ce{Na_{2}CO_{3} ightarrow 2Na^{+} + CO_{3}^{2-}}$
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a popular sports drink has 30.43 g of the sugar sucrose in 500. ml of t…
\( 0.178 \)
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john measures out the required 150 ml of 6% h₂o₂ in a graduated cylinde…
150
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john dilutes some 6% (or 1.76 m) h₂o₂ to 3% (or 0.88 m) in order to cre…
150
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hydrogen fuel cells are a promising source of energy. which of these is…
water
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predict the products for the reaction. solutions of acetic acid and pot…
$\ce{KC2H3O2(aq) + H2O(l)}$ (the option: $\ce{KC2H3O2(aq) + H2O(l)}$)
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what is the balanced net ionic equation for the reaction below? hi(aq) …
A. \(H^+(aq) + OH^-(aq) ightarrow H_2O(l)\)
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2nh₄oh + kal(so₄)₂ + h₂o → 2al(oh) + (nh₄)₂so₄ + koh +
To balance the chemical equation \( 2NH_4OH + KAl(SO_4)_2 + H_2O ightarrow Al(OH)_3 + (NH_4)_2SO_4 + KOH + H_2O \) (note: there's a duplicate \( H_2O \) which we'll address), we f…
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what is the net ionic equation for the reaction between calcium nitrate…
$\boldsymbol{\ce{Ca^{2+} + SO4^{2-} -> CaSO4}}$ (the fourth option: $\ce{Ca^{2+} + SO4^{2-} -> CaSO4}$)
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as labeled in this diagram, which layer contains all naturally occurrin…
D. The outermost layer (labeled D, the crust)