化學
化學反應、化學計量、分子結構與元素性質。
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9. a generator converts 103,200,000 j of chemical energy into 40,932,20…
D. 39%
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use the reaction and bond information to answer the question. \\(\\ce{h…
1983 kJ
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use the reaction and bond information to answer the question. \\ce{h_{2…
# Explanation: ## Step1: Determine bonds in product ($\ce{CH2O2}$) First, we need to figure out the bond structure of $\ce{CH2O2}$. The Lewis structure of $\ce{CH2O2}$ (formic aci…
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when a bond is very strong, then the (1 point) bond energy is low. proc…
D. bond energy is high, C. process to break it is endothermic Wait, no - the options are: 1. bond energy is low. 2. process to break it is exothermic. 3. process to break it is en…
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what information does this image give about the reaction taking place? …
A. It is an exothermic reaction because the system is giving heat and light to the surroundings.
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3. the next two parts are connected. answer each of the following. a. a…
a. $\text{C}_4\text{H}_3\text{O}_2$ b. $\text{C}_{16}\text{H}_{12}\text{O}_8$
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a cold pack is broken, allowing two chemical substances to mix, making …
The system gains energy from the surroundings.
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use the reaction to answer the question.\\(\\ce{ch_{4} + 2o_{2} -> co_{…
-698 kJ/mol (the option: -698 kJ/mol)
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3. the next two parts are connected. answer each of the following. a. a…
$\text{C}_4\text{H}_3\text{O}_2$
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use the reaction to answer the question. $\\ce{ch_{4} + 2o_{2} -> co_{2…
\(-698\) kJ/mol (corresponding to the option: \(-698\) kJ/mol)
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energy in chemical reactions complete this assessment to review what yo…
The enthalpy change of the reaction is $\boldsymbol{-698\ \text{kJ/mol}}$ (indicating an exothermic reaction).
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6. which of the elements in the following reaction has been reduced? zn…
Hydrogen
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use the reaction to answer the question. $\\ce{ch_{4} + 2o_{2} \ ightar…
The enthalpy change of the reaction is \(\boldsymbol{-698 \, \text{kJ/mol}}\) (exothermic, as \(\Delta H\) is negative).
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5. a student combines solutions of silver nitrate, agno₃, and sodium ch…
precipitation reaction
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energy in chemical reactions i online practice complete this assessment…
A. Heat and light are absorbed from the environment.
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2. what is the empirical formula of a molecule containing 14.7% carbon,…
$\text{C}_2\text{H}_3\text{O}_5\text{N}_4$
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2. which of the reactions below are replacement reactions? select two c…
A. $\text{Mg}(s) + 2\text{HCl}(aq) ightarrow \text{H}_2(g) + \text{MgCl}_2(aq)$ C. $\text{Zn}(s) + 2\text{HCl}(aq) ightarrow \text{ZnCl}_2(aq) + \text{H}_2(g)$
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4. what type of reaction generally occurs when oxygen combines with an …
combustion
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answer each of the following your notes as an example if needed. 1. wha…
$\text{C}_2\text{H}_5\text{O}_2$
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11. what are the oxidation numbers in the compound fe₂o₃? options: fe=-…
B. Fe = +3, O = -2
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what are the basic parts of chemical equations? complete the following …
- Reactants and products are written as **chemical formulas** within a chemical equation. - **Reactants** of a chemical equation are written to the left of the arrow. - **Products…
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footing and perfect unreserve which had soon followed isabellas⁴ marria…
C. It hints at the main theme. ### Question 11
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14. which of the following is a balanced chemical equation describing t…
$\boldsymbol{2H_2 + O_2 ightarrow 2H_2O}$ (the fourth option)
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13. what happens to the atoms of the reactants in a chemical reaction? …
They recombine to form the products.
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4. complete the following table containing ionic and/or covalent compou…
### Problem 4: Completing the Table (Chemical Compounds) Let's tackle each row of the table: #### 1. Chemical Formula: $\boldsymbol{CaSO_4}$ - **Name of Compound**: Calcium Sulfat…
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9. the graph shows the phase diagram for a substance q, temperature aga…
A. 1: solid; 2: triple point; 3: gas; 4: liquid ### Question 10
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10. directions drag and drop the correct answer choice to each answer b…
$\text{Fe(NO}_3\text{)}_2$
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lewis dot diagram worksheet draw the lewis dot diagram of the following…
1. $F_2$ (completed): $:\ddot{F}-\ddot{F}:$ 2. $NO$: $:\dot{N}=\ddot{O}:$ 3. $O_2$ (completed, corrected): $:\ddot{O}=\ddot{O}:$ 4. $HCN$: $H-C\equiv N:$ 5. $H_2S$: $\begin{matrix…
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select the correct answer. which type of electromagnetic wave is invisi…
B. ultraviolet rays
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32. what are the reactants in the following chemical reaction? $\\ce{ch…
B. $\text{CH}_4$ and $2\text{O}_2$
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31. compounds that form when electrons are transferred between a metall…
ionic compounds
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26. which of the following is not a use for gold? electronics in comput…
making glass
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which of the following does not occur naturally and must be made in a l…
D. methamphetamine
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20. what is the most common basis for the classification of minerals? t…
C. chemical composition
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17. why is limestone considered an organic sedimentary rock? it is form…
B. It is formed from minerals that came from organisms that were once living.
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15. why are brick, steel, and glass not classified as minerals even tho…
A. They are not naturally occurring.
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11. the bonneville salt flats in utah were formed by water evaporating …
chemical sedimentary
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fill in the correct formula and type of bond for aluminium oxide. a alo…
C. $\text{Al}_2\text{O}_3$, ionic
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part a fill in the correct name and type of bond for mgo a magnesium ox…
A. Magnesium oxide, ionic
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what are the characteristics of fixed poetry? select three options. a r…
- a regular rhyme scheme - lines of equal length - a set number of lines
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when magnesium (mg²⁺) and fluorine (f¹⁻) combine in an ionic bond, the …
D. $\text{MgF}_2$
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how should you change this image to represent an ionic bond between sod…
C. Move one electron from sodium to fluorine.
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the rhyme pattern that occurs at the ends of lines in poetry is called …
D. a rhyme scheme
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mgx₂ very low density highly reactive diatomic using the periodic table…
A. fluorine
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the difference between the carbon-12 and carbon-14 isotopes is the a at…
C. number of neutrons.
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as we move across the periodic table of elements, certain trends are ev…
B. Nonmetallic character increases moving left to right. C. Electron affinity increases across the periodic table.
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elaborate on what can be learned about the properties by the location o…
C. It is a main group metal, has 3 valence electrons, becomes a cation with a +3 charge, and is ductile, malleable, and conductive.
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12. which biogeochemical cycle does not take place in the atmosphere? ○…
D. phosphorus cycle
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final final equation h-1 h-1 2 h₂ + o₂ → 2 h₂o o-2 o-2 h-1 h-1 2 h₂o₂ →…
To balance the chemical equations, we'll follow the steps of counting atoms on each side and adjusting coefficients. Let's take one equation at a time (e.g., $\boldsymbol{2H_2 + O…
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make the following equations on your desk reactants start products star…
To balance these chemical equations, we'll use the method of balancing by adjusting coefficients to ensure the number of each atom is the same on both sides of the equation. ### 1…
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make the following equations on your desk reactants start products star…
To balance the chemical equations, we follow these steps for each: ### 1. $\boldsymbol{H_2 + O_2 ightarrow H_2O}$ - **Step 1: Count atoms on each side.** Reactants: $H = 2$, $O = …
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make the following equations on your desk | | reactants start | product…
To solve these chemical equations, we need to balance them by ensuring the number of each type of atom is the same on both sides of the equation. Here are the balanced equations f…
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ch₂o # v electrons ____ ch₂s # v electrons ____ ch₄ # v electrons ____ …
CH₄O: 14 CH₃S: 13 CH₄: 8 CH₃F: 14 CH₃OH: 14 C₂H₆: 14
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lewis dot structure practice name: pd. date: rules for drawing lewis do…
NI₃ # v electrons: 26 O₂ # v electrons: 12 H₂S # v electrons: 8 N₂ # v electrons: 10 PF₃ # v electrons: 26 SiO₂ # v electrons: 16
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continued... part c. fill in the chart substance\tmoles (mol)\tmass (g)…
s (partial, as others need more info): 11. $\boldsymbol{43.57\ g}$ (or ~43.56 g) 13. $\boldsymbol{5.83\ g}$ (or ~5.83 g) 14. $\boldsymbol{2.00\ mol}$ (or ~2.0 mol) (Note: For prob…
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continued... part c. fill in the chart substance\tmoles (mol)\tmass (g)…
### Part C (Taking Question 11 as an example) # Explanation: ## Step1: Calculate molar mass of \( K_2SO_4 \) Molar mass of \( K = 39.10 \, g/mol \), \( S = 32.07 \, g/mol \), \( O…
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consider the precipitation reaction: bacl₂ + 2 agno₃ → 2 agcl + ba(no₃)…
120 g of AgCl (the option: 120 g of AgCl)
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consider the precipitation reaction: bacl₂ + 2 agno₃ → 2 agcl + ba(no₃)…
120 g of AgCl (Option: 120 g of AgCl)
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how many moles of sulfur trioxide are formed from 5 moles of sulfur dio…
5 mol of \(SO_3\) (the option: 5 mol of \(SO_3\))
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what is the mass of 0.94 mol of nh₃? the molar mass of nh₃ is 17.03 g/m…
16 g (corresponding to the option "16 g")
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what is the molar mass of cortisol (c₂₁h₃₀o₅), a steroid hormone produc…
362.5 g/mol (the option with 362.5 g/mol)
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Question was provided via image upload.
4
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what is the missing coefficient in the following chemical equation? 2h₂…
2 (So the coefficient is 2, corresponding to the option "2")
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in the balanced chemical equation for the formation of ammonia: 3h₂(g) …
the option "there are two molecules of \(NH_3\) present" (the second option in the list)
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the law of conservation of matter justifies the reason that chemical re…
A. true
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how many zinc atoms are contained in 4.6 moles of zinc? ○6.02 × 10²³ zi…
\( 2.8\times 10^{24} \) zinc atoms (the last option: \( 2.8\times 10^{24} \) zinc atoms)
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the molecular formula is c₆h₁₂o₆ because one molecule actually co for t…
| Formula | Numbers of atoms | |---------------|-----------------------------------| | $\text{CaCl}_2$ | $\text{Ca}=1; \text{Cl}=2$ | | $\text{CO}_2$ | $\text{C}=1; \text{O}=2$ | …
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1 mole (6.02 × 10²³ mg atoms) 24.31 grams mg 1 mole 1 mole 24.31 grams …
The correct option is the second one: \(\boldsymbol{\frac{24.31 \text{ grams Mg}}{1 \text{ mole}}}\) (the option with \( \frac{24.31 \text{ grams Mg}}{1 \text{ mole}} \) as its co…
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which conversion factor should be used when converting from the number …
The conversion factor is \(\frac{1\ \text{mole}}{6.02\times 10^{23}\ \text{Mg atoms}}\) (corresponding to the option with \(\frac{1\ \text{mole}}{(6.02\times 10^{23}\ \text{Mg ato…
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which of the following statements is correct regarding avogadro’s numbe…
C. Avogadro’s number is the number of $CO_2$ molecules in one mole of $CO_2$. (Note: Assuming the third option is labeled as C here, based on the standard multiple - choice labeli…
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which of the following statements is correct regarding avogadro’s numbe…
C. Avogadro’s number is the number of \(\ce{CO2}\) molecules in one mole of \(\ce{CO2}\) (Note: Assuming the third option is labeled "C" based on typical multiple - choice numberi…
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which of the following statements is correct regarding avogadro’s numbe…
C. Avogadro’s number is the number of \(CO_2\) molecules in one mole of \(CO_2\) (assuming the third option is labeled C; adjust label as per original, but the correct statement i…
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what is the chemical formula for dinitrogen tetroxide? $\\circ$ $\\ce{n…
C. \( \text{N}_2\text{O}_4 \) (assuming the third option is labeled C, with the formula \( \text{N}_2\text{O}_4 \))
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identify the correct name for the compound no₂ which is a red - brown c…
C. nitrogen dioxide
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what is the formula for the ionic compound aluminum oxide?\ \\bigcirc a…
D. \( \text{Al}_2\text{O}_3 \) (assuming the last option with the correct formula is labeled as such, but based on the options, the correct one is \( \text{Al}_2\text{O}_3 \))
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what is the name of the compound (nh₄)₃po₄? ○ammonium phosphide ○triamm…
D. ammonium phosphate
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what is the proper name for $\\ce{mgbr_{2}}$? \\bigcirc magnesium bromi…
A. magnesium bromide
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what is the ion symbol for the phosphide ion? options: - $\\ce{p^{2-}}$…
D. $p^{3 - }$ (assuming the last option is labeled D, with the option text $p^{3 - }$)
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which of the following elements will most likely form a covalent bond? …
B. nitrogen and chlorine
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which of the following could represent an ion symbol for an atom with 1…
\( \boldsymbol{K^+} \)
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neon-22 contains ______ neutrons. 10 12 22 2
12 (and the correct option is the one with 12, i.e., the option marked with the blue dot, which is the option labeled "12")
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neon-22 contains ______ neutrons. 10 12 22 2
12 (The correct option is the one with 12, so if we consider the options as: 10, 12, 22, 2; the answer is the option with 12, e.g., if the options are labeled as: the option with …
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thallium-201 is a radioactive isotope used in the diagnosis of coronary…
201 (corresponding to the option with 201)
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part 5: energy diagrams a. exothermic reaction - draw an energy diagram…
### A. Reacción Exotérmica #### Explicación del Diagrama: 1. **Ejes**: El eje vertical representa la energía ($E$), el eje horizontal representa el progreso de la reacción (tiempo…
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the name of the noble gas in period 3 is ______. ○helium ○neon ○krypton…
D. argon
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name _______________________________ due friday, january 25, 2026 celeb…
A dry can won't collapse because there's no water to vaporize and then condense, so the pressure inside and outside the can remains relatively equal (no large pressure difference …
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what is the chemical symbol for the halogen located in period 5? ○i ○xe…
A. I
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which element is a metal? k si p kr more than one of the elements is a …
A. K
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in which state(s) is/are the particles randomly arranged? solids only l…
E. liquids and gases
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an unknown solid is taken to the laboratory for analysis. which of the …
The substance produces a gas when combined with $\ce{NaHCO_{3}}$ in water.
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a 15.0 ml urine sample from a dehydrated patient has a density of 1.019…
$1.53 \times 10^4$ mg (corresponding to the option "1.53 × 10⁴ mg")
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celebration of molecules, solids, liquids, gases, and intermolecular fo…
### Part 1: Adding Water Molecules (Intermolecular Forces - Hydrogen Bonding) Water molecules (\(H_2O\)) have a bent structure with a partial negative charge on the oxygen (\(O\))…
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convert the 39.8°c to kelvin. ○313 k ○4.33 k ○71.8 k ○129 k
313 K (the option corresponding to this value, e.g., if the first option is "313 K", then the answer is the option with "313 K")
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what is the correct metric relationship between milliliters and microli…
C. 1 milliliter = 1,000 microliters (assuming the options are labeled A to E with the third option being C; if the original options have different labels, adjust accordingly, but …
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which measured value contains a zero that is not a significant figure? …
B. 0.984
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19. choose the product that best provides evidence of chemical change w…
19. precipitate 20. synthesis
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17. choose the product that best provides evidence of chemical change w…
17. gas 18. $\text{Cu}^{2+}$, $\text{Mg}^{2+}$
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18. choose all that apply. identify the two cations in the following ch…
1. For the reaction $\ce{Na2S(aq) + 2HCl(aq) -> 2NaCl(aq) + H2S(g)}$: gas 2. For the reaction $\ce{Mg(s) + Cu(NO3)2(aq) -> Mg(NO3)2(aq) + Cu(s)}$: $\ce{Cu^{2+}}$, $\ce{Mg^{2+}}$
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15. choose the best answer. the following chemical equation shows the f…
15. $\text{Fe(NO}_3\text{)}_3(aq)$ 16. thermal decomposition
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13. choose the best answer. when an ionic compound is dissolved in wate…
13. a. dissociation 14. $\text{MgCO}_3(s) ightarrow \text{MgO}(s) + \text{CO}_2(g)$