化学
化学反応、化学量論、分子構造、元素の性質。
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predicting the products of a replacement reaction based on the replacem…
\(OH\) (The formula of the compound is \(Be(OH)_2\), so the missing part in the formula \(Be(\underline{OH})_2\) is \(OH\))
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question 1 1 pts identify the reactant that will result in a precipitat…
D. $\boldsymbol{Pb(NO_3)_2 + NaCl}$
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if carbon monoxide reaches a temperature of over 1,100 degrees fahrenhe…
\( 2\text{CO}_2 \) (the first option: \( 2\text{CO}_2 \))
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predicting the products of a synthesis reaction based on the synthesis …
C. NaCuPO₄ (assuming option 3 is labeled C, as per the options shown: third option is NaCuPO₄)
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for the chemical equation below, list the stoichiometric coefficients i…
A. 2 : 25 : 16 : 18
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for the chemical equation below, list the stoichiometric coefficients i…
3:2:1:6 (corresponding to the option "3:2:1:6")
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predicting the products of a decomposition reaction if calcium carbonat…
\(CaO\)
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identifying types of chemical reactions identify the reaction type for …
- \( A + B ightarrow AB \): Combination (Synthesis) Reaction - \( AB ightarrow A + B \): Decomposition Reaction - \( \text{Hydrocarbon} + \text{O}_2 ightarrow \text{CO}_2 + \text{…
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6. the moon was once believed to have no water anywhere on its surface.…
If the Moon had no water, there could not be aqueous solutions (solutions with water as the solvent) because a solvent (water) is required for an aqueous solution. However, non - …
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question 35 as the concentration of solute in a solution becomes more c…
A. The freezing point of the solution is less than the freezing point of the pure solvent B. The boiling point of the solution is greater than the boiling point of the pure solven…
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will the freezing point of a solution be higher or lower compared to th…
lower ### Question 33 (Lowest Freezing Point)
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the molality of a mgcl₂ solution is 1.44 m. how many total ions does mg…
Total ions: 3; Total molality: 4.32 m ### For sugar (C₆H₁₂O₆) solution:
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question 26 fill in the blanks below to show how to use 5.00 m hbr solu…
Combine \(\boldsymbol{1.10 \, L}\) (or 1100 mL) of \(\boldsymbol{5.00 \, M}\) \( HBr \) solution with \(\boldsymbol{0.90 \, L}\) (or 900 mL) of water to make 2.00 L of 2.75 M \( H…
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a certain solution of salt water has a molality of 8.12 m. how many mol…
For 1 kg: $\boldsymbol{8.12}$ mol For 5 kg: $\boldsymbol{40.6}$ mol ### Question 24 (Molality of sucrose solution)
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question 20 how many mol of naoh are present in 646 ml of 1 m solution?…
0.65 ### Question 21
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a solution is prepared by dissolving 45 g of salt in 318 g of water. wh…
To find the mass percent of salt: 1. **Total mass of solution**: \( 45\,\text{g (salt)} + 318\,\text{g (water)} = 363\,\text{g} \). 2. **Mass percent formula**: \( \text{Mass}\,\t…
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part 1 of 2 makenzie dissolved 22.0 g auf₃ in enough distilled water to…
\( 0.204 \, \text{mol/L} \) (or unrounded \( \approx 0.2038 \, \text{mol/L} \)) ### Now, Question 16 (Mass percent of salt):
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3. susan makes the following entry in her notebook: \on friday we were …
The blue liquid was a solution. Because a solution is a homogeneous mixture where a solute dissolves in a solvent, and here after the liquid (solvent) evaporated over the weekend,…
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in general, what conditions would best encourage the solubility of a ga…
C. a high atmospheric pressure, low Temperature ### Question 12 (Atmospheric pressure and oxygen solubility at high altitude)
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the table below shows the solubility of different substances at substan…
saturated (Note: Wait, no—wait, I think I made a mistake. Wait, 114 g per 100 g water. So for 54 g water, the maximum solute is (114/100)*54? Wait, no, that's 61.56 g. But 122 g i…
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question 9 use the \solubility curves\ graph for various ionic compound…
A. 100 g A.i. Yes, will dissolve B. 180 g (approximate, based on graph) B.i. No, won't dissolve (Note: The solubility values are approximate from the given graph. The exact values…
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question 8 using the solubility rules located on your \green sheet\, de…
s (for each "Select an answer"): - MgO: insoluble, (s) - ZnCO₃: insoluble, (s) - Mg₃(PO₄)₂: insoluble, (s) (Note: If the question is to correct the existing wrong ones too, the co…
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name: 1. state, with a reason, whether each of the following is a homog…
## Part 1 Answers: 1a. Heterogeneous (mechanical) mixture - has visible non - uniform components (e.g., pickle chunks). 1b. Heterogeneous (mechanical) mixture - has visible pulp. …
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question 6 water is a polar solvent and hexane is a non - polar solvent…
For \(C_{12}H_{23}O_{11}\): polar substance (based on "like dissolves like" as it dissolves in polar water and not in non - polar hexane) Sugar: soluble in water (polar solvent, s…
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which of the following best represents how an ionic compound is dissolv…
The bottom - most diagram (with blue oval - shaped ions and red/white water - like molecules surrounding them, showing polar attraction between water and ions)
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which of the following best represents how a polar covalent compound is…
The first diagram (the one with the blue oval with a + sign and red - white water - like molecules surrounding it)
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based on the chemical formula provided, classify each compound as a str…
A. Strong Electrolyte B. Weak Electrolyte C. Nonelectrolyte D. Nonelectrolyte E. Strong Electrolyte F. Weak Electrolyte G. Strong Electrolyte H. Strong Electrolyte
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question 2 choose the correct words for the spaces. in any solution, th…
First blank: solute; Second blank: solvent
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question 1 choose the correct words for the spaces. an select an answer…
First blank: aqueous (from the options: aqueous), second blank: water (assuming it's an option, but based on the first dropdown, the first correct selection is "aqueous" for the f…
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chapter assessment identify each property as either physical or chemica…
1. physical, intensive 2. chemical 3. physical, intensive 5. physical, extensive 6. chemical 7. physical, intensive 8. physical, intensive 9. b, c 10. a, d 11. b, d 12. c 8. homog…
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the equation below shows a general equation for a reaction, and the amo…
The amount of CD is 35 g, and the amount of AC is 40 g.
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substances a and b react in a ratio of a + b → ab. colin was combining …
55 g (the option with 55 g)
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if the mass of the products measured 120 g, what would be the mass of t…
120 g (corresponding to the option "120 g")
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one half of a balanced chemical equation is shown. 3mg(oh)₂ + 2h₃po₄ wh…
3 Mg, 2 P, 14 O, 12 H (the first option)
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the equation below is for potassium oxide. 4k + o₂ → 2k₂o what is the r…
2:1
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matter— reviewing vocabulary match the definition in column a with the …
s for Matching: 1. d. solution 2. c. law of conservation of mass 3. b. periodic table 4. a. percent by mass 5. g. states of matter 6. e. crystallization 7. f. chromatography 8. i.…
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kiley wants to balance the equation $\\ce{h_{2} + n_{2} -> nh_{3}}$. wh…
D. creating a chart that shows the number of atoms in the reactants and products
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which is the balanced equation for $v_2o_5 + cas \ ightarrow cao + v_2s…
\( V_2O_5 + 5CaS ightarrow 5CaO + V_2S_5 \) (the last option among the given choices)
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charlie is balancing an equation. she has identified the atoms and coun…
A. coefficients
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based on the chemical equation, use the drop - down menu to choose the …
The coefficients are 1 (for Zn), 2 (for HCl), 1 (for \(ZnCl_2\)) and 1 (for \(H_2\)). So the balanced equation is \(1Zn + 2HCl ightarrow 1ZnCl_2 + 1H_2\)
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based on the chemical equation, use the drop - down menu to choose the …
The coefficients are 3 for \(O_2\) and 2 for \(O_3\), so the balanced equation is \(3O_2 ightarrow 2O_3\) (or in the boxes: first box 3, second box 2).
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based on the chemical equation, use the drop-down menu to choose the co…
1 (for \( \text{BaO}_2 \)), 1 (for \( \text{H}_2\text{SO}_4 \)), 1 (for \( \text{H}_2\text{O}_2 \)), 1 (for \( \text{BaSO}_4 \))
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based on the chemical equation, use the drop-down menu to choose the co…
The coefficients are 1 for CaSO₄, 2 for O₂, and 1 for CaS. So the blanks are filled with 1, 2, 1 respectively.
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based on the chemical equation, use the drop-down menu to choose the co…
2, 1, 1 (coefficients for $\ce{Na2HPO4}$, $\ce{Na4P2O7}$, $\ce{H2O}$ respectively)
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based on the chemical equation, use the drop - down menu to choose the …
First coefficient (H₂O): 2, Second coefficient (H₂): 2, Third coefficient (O₂): 1
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based on the chemical equation, use the drop-down menu to choose the co…
1 (for \( \text{Li}_2\text{O} \)), 1 (for \( \text{H}_2\text{O} \)), 2 (for \( \text{LiOH} \))
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number the steps for balancing equations: use coefficients to increase …
1. Identify the atoms on each side. 2. Count the atoms on each side. 3. Use coefficients to increase the atoms on each side. 4. Check to make sure you have the same number of each…
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complete the text with the better conjunctive adverb. scientists believ…
Consequently
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the gulf of america dead zone is an area of hypoxic waters at the mouth…
A. Control of animal wastes so that they are not allowed to enter into waterways. B. Adjust the timing of fertilizer applications to limit runoff of excess nutrients from farmland…
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question: on the fahrenheit scale, the freezing point of water is desig…
32
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which best explains why sawdust burns more quickly than a block of wood…
C. More molecules in the sawdust can collide with oxygen molecules. (Note: Assuming the options are labeled A, B, C, D with the third option being C as per the standard multiple -…
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the production of water proceeds according to the following equation. $…
C. Place the reactants in a smaller container.
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an increase in temperature affects the reaction rate by decreasing the …
B. increasing the number of molecules that have sufficient kinetic energy to react.
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question: when the molecules of a body move less rapidly, heat energy i…
reduced
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a solid reactant is placed into a beaker of a warm water. the liquid vi…
B. Fewer bubbles will be produced because of fewer collisions of reactant molecules.
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question: the temperature of a body depends on the ____. answer options…
average velocity of the body's molecules
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which topic is commonly used to explain activation energy and how chemi…
B. collision theory
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consider the reaction below. 2nh₃(g) ⇌ n₂(g) + 3h₂(g) which is most lik…
The reaction rate decreases.
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which term refers to the speed at which reactants are converted into pr…
A. reaction rate
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what does a person study when learning computer science? a. the interac…
D. Computers, their components, and their use to solve problems
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Question was provided via image upload.
A. Particles need to collide in order to react.
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what does this piece of evidence best support? the collision theory the…
A. the collision theory
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the synthesis of water proceeds according to this equation: 2h₂(g) + o₂…
A. by increasing the temperature of the reactants
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3. nh₃ is normally encountered as a gas with a pungent odor. it is form…
The equilibrium value of \([\ce{NH_{3}}]\) is approximately \(\boldsymbol{8.3\times10^{-5}\space mol/L}\) (or more precisely \(8.31\times10^{-5}\space mol/L\))
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can combine with water to form carbonic acid. then, h₂co₃ falls as rain…
1. "During this process, rocks on land are broken down by carbonic acid, forming various ions. Carbon is removed from the atmosphere." - chemical weathering 2. "During this proces…
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14) i heart electron config 1) instructions: using the one filled box a…
8 (except He, which has 2) ### Part 3: How many valence electrons do Group 1 elements (Li, Na, K, etc.) have? ## Step 1: Recall Group 1 Configurations Group 1 elements have one va…
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6. two compounds of hydrogen and oxygen are tested. compound i contains…
Ratio for Compound I: $\boldsymbol{8}$, Ratio for Compound II: $\boldsymbol{16}$ ### Part (b)
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7. predict which bond is the most polar (has electrons that are pulled …
Ge - F
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6. two compounds of hydrogen and oxygen are tested. compound i contains…
Compound I: 8:1, Compound II: 16:1 ### Question 6b
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6. two compounds of hydrogen and oxygen are tested. compound i contains…
Compound I: $8.0$, Compound II: $16.0$ ### Part 6b
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chemistry fall semester final exam review (25-26) the atom 1. which of …
a. The # of Protons ### Question 2
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sample. b. could the sugar in corn syrup be sucrose? justify your concl…
a. Percent by mass: Hydrogen \(5.0\%\), Fluorine \(95.0\%\) b. Mass of hydrogen in 50g sample: \(2.5\,\text{g}\) c. Justified by the Law of Definite Proportions (fixed % compositi…
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energy concentration game directions after playing several rounds of co…
### Definitions (Sample Answers): - Chemical Energy: Energy stored in chemical bonds. - Elastic Potential Energy: Energy in stretched/compressed elastic materials. - Electrical En…
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in the compound. 2. a similar chemical analysis is performed on a 500.0…
(for part a): - Carbon: $42.20\%$ - Hydrogen: $6.50\%$ - Oxygen: $51.30\%$ (For part b: Yes, the percent compositions are very close to sucrose’s, so it could be sucrose.)
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the initial temperature of a bomb calorimeter is 28.50°c. when a chemis…
5,170 J (The option with 5,170 J, assuming the last option is D. 5,170 J (if options are labeled A to D as per order: A. 140 J, B. 418 J, C. 1,470 J, D. 5,170 J then D. 5,170 J))
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standard enthalpies of formation substance\tδhf (kj/mol) c₂h₂ (g)\t−26.…
$\boldsymbol{\Delta H_{rxn} = -92.38\,\text{kJ}}$ (Option: $\Delta H_{rxn} = -92.38\,\text{kJ}$)
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sulfur reacts with oxygen to form sulfur dioxide (so₂(g), δhf = -296.8 …
-296.8 kJ (corresponding to the option: -296.8 kJ)
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which of the following statements is true? the overall chemical reactio…
The overall chemical reaction is exothermic.
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consider the following enthalpy diagram and enthalpies of intermediate …
Using Hess's Law, the relationship between the enthalpies is $\boldsymbol{\Delta H_{rxn} = \Delta H_1 + \Delta H_2 - \Delta H_3}$ (or adjusted based on precise diagram interpretat…
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describe what happened on april 22, 1915
On April 22, 1915, during World War I, the German army launched the first large - scale chemical attack (using chlorine gas) at the Second Battle of Ypres, causing heavy casualtie…
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5. predict the order of increasing electronegativity in each of the fol…
Se < S < Cl
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complete combustion of a 0.350 g sample of a compound in a bomb calorim…
25.8°C (corresponding to the option: 25.8°C)
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which statement best describes the direction of heat flow by conduction…
B. Heat flows from faster molecules to slower molecules when they collide.
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what explains the key difference between a bomb calorimeter and a coffe…
C. A bomb calorimeter has a separate chamber to hold substances and can even measure heat gain or loss for reactions that do not occur in water.
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consider the following intermediate chemical equations. c(s) + \\(\\fra…
B. \(O_2(g)\) as a reactant (assuming the options are labeled as A, B, C, D with B being \(O_2(g)\) as a reactant)
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which describes the enthalpy change associated with an endothermic reac…
B. It is positive because the enthalpy of the products is greater than the enthalpy of the reactants. (Assuming the second option is labeled B; adjust label based on actual questi…
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how should the baking of a pizza be categorized? as an exothermic proce…
D. as an endothermic process because the dough absorbs heat (assuming the options are labeled A, B, C, D in order; if original labels differ, adjust, but based on the order: the f…
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ammonia, nh₃(δhᵢ = -45.9 kj), reacts with oxygen to produce water (δhᵢ …
-902 kJ
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which statement about enthalpy is true? the enthalpy of formation for a…
Enthalpy is a state function because its change depends only on initial and final conditions.
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consider the following intermediate chemical equations. c(s)+o₂(g)→co₂(…
B. Reverse the second equation, and change the sign of the enthalpy. Then, add.
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which reaction is endothermic? hcl + naoh → nacl + h₂o + 58 kj 6co₂ + 1…
B. \( 6\ce{CO_2} + 12\ce{H_2O} + \text{energy} ightarrow \ce{C_6H_{12}O_6} + 6\ce{O_2} + 6\ce{H_2O} \)
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nitrogen dioxide, no₂(g) (δhᵢ = 33.84 kj/mol), is decomposed according …
84.6 kJ of energy released (corresponding to the option: 84.6 kJ of energy released)
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consider the following intermediate chemical equations. c(s) + \\frac{1…
A. Cancel out CO because it appears as a reactant in one intermediate reaction and a product in the other intermediate reaction.
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which statement defines calorimetry? the conservation of energy a unit …
D. the measurement of energy that is given off or absorbed in a physical or chemical process (assuming the last option is D; if option labels are different, adjust accordingly wit…
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a welding torch produces a flame by burning acetylene fuel in the prese…
A. chemical energy into thermal energy
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4. the ionic radii of the ions $s^{2-}$, $cl^-$, and $k^+$ are 184, 181…
These ions (\( S^{2-} \), \( Cl^{-} \), \( K^{+} \)) are isoelectronic (same number of electrons) but have different nuclear charges (16, 17, 19 protons respectively). A higher nu…
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4. the ionic radii of the ions $s^{2-}$, $cl^-$, and $k^+$ are 184, 181…
These ions are isoelectronic (same electron count, 18 electrons) but have different nuclear charges (proton numbers: \( \text{S}^{2-} = 16 \), \( \text{Cl}^- = 17 \), \( \text{K}^…
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an ice cube is dropped into a glass of milk at 20°c. which statement ex…
A. Because milk has higher KE than ice, KE is transferred from the milk to the molecules of ice (assuming the first option is labeled A; if options have different labels, adjust a…
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which statement describes mechanical energy? ○ the energy that is store…
the sum of the kinetic energy and the potential energy of an object
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when ammonium chloride is dissolved in water, the beaker gets cold. whi…
B. endothermic