化学
化学反応、化学量論、分子構造、元素の性質。
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14) the density of copper is 8.96 g/ml. the volume of 12 mg of copper i…
0.0013 mL
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reduction half - reaction 3e⁻ + 2h₂o + mno₄⁻ → mno₂ + 4oh⁻ oxidation ha…
2
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15) a sample of an alloy (density = 9.62 g/cm³) was submerged in a grad…
$\square$ 149 g
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how many electrons do you need to add? 6oh⁻ + br⁻ → bro₃⁻ + 3h₂o + ?e⁻
6
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15) a sample of an alloy (density = 9.62 g/cm³) was submerged in a grad…
149 g
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which side will the electrons go on? 6oh⁻ + br⁻ → bro₃⁻ + 3h₂o a. add e…
B. Add electrons to the product side.
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how many water molecules go on the product side? 6oh⁻ + br⁻ → bro₃⁻ + ?…
3
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now lets look at the oxidation half - reaction. for the oxidation half …
6
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how many electrons must be added to the reactant side? ?e⁻ + 2h₂o + mno…
3
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determine the overall charge on each side of the arrow. which side shou…
A
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naming & writing formulae for covalent compounds prefixes: 1 mono- 2 di…
### Write the name: a) phosphorus trichloride b) dinitrogen pentoxide c) tetraphosphorus decoxide d) carbon tetrabromide e) dichlorine monoxide ### Write the formula: f) $\text{P}…
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how many water molecules should be added to the reactant side? ?h₂o + m…
2
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question 20 0.5 pts if the mineral azurite contains 55.1% copper by mas…
305g (corresponding to the option with 305g)
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question 19 0.5 pts if there are 21 blonde students in a chemistry clas…
32.3%
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the reaction needs two more oxygen atoms on the product side. how many …
2
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question 18 how many \\(\\mathrm{cm^3}\\) are in a 1.50 quart bottle? \…
A. $1.42\times 10^{3}\ \text{cm}^3$
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the reduction half - reaction shows the need for two more oxygen atoms …
B
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the road not taken by robert frost two roads diverged in a yellow wood,…
## Task 1: Structure 1. The poem is split into 4 5-line stanzas, following a narrative of choice, reflection, doubt, and retrospective storytelling. 2. The rhyme scheme is ABAAB; …
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the reduction half - reaction shows the need for two more oxygen atoms …
B. hydroxide
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sodium bromide and potassium permanganate undergo a redox reaction in b…
B
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33) ca-40, k-39, and sc-41 all have the same (4pts) □ atomic mass. □ at…
number of neutrons.
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32) ions can be formed from atoms by losing or gaining electrons. selec…
13 protons, 14 neutrons, and 10 electrons
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1) the element with atomic number 53 always contains (3pts) □ 53 neutro…
53 protons.
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30) the species shown below which has 24 neutrons is (3pts) \\(_{24}^{5…
$\boldsymbol{^{45}_{21}Sc}$
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28) which pair of formulas illustrates the law of multiple proportions?…
$\boldsymbol{\text{CuO and CuO}_2}$
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27) the specific heat of zinc is 0.388 j/g°c. a 700.0 g sample of zinc …
$\square$ 43.6 $^\circ$C
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26) the specific heat of aluminium is 0.900 j/g°c. how much energy is r…
$\boldsymbol{877\ \text{J}}$ (Option: $\boldsymbol{\square\ 877\ J}$)
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23) 3.17 g of sodium combines with chlorine to form 8.00 g of sodium ch…
4.83 g ---
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21) which of the following is chemical property of iodine? (3pts) □ blu…
$\square$ blue black color $\square$ shiny crystals $\square$ sharp odor $\checkmark$ corrosive vapor --- ### Question 22
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20) which element is not reactive? (3pts) fluorene sodium argon boron
□ Argon
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chemistry 1 ionic nomenclature 1 complete the table following the examp…
a. Aluminum chloride b. Magnesium sulfide c. Aluminum nitride d. Sodium sulfide e. Calcium fluoride --- ### 3. Completed Table (Ionic Compound Formulas & Names)
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18) which element forms diatomic molecules? (3pts) □ carbon □ bromine □…
18) bromine 19) 21
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17) the alkali metals are in group ____. (3pts) □ 1a □ 2a □ 5a □ 7a
$\boldsymbol{\square}$ 1A
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16) which would you classify as a semiconductor? (3pts) diamond silicon…
□ Silicon
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14) the density of copper is 8.96 g/ml. the volume of 12 mg of copper i…
14) 0.0013 mL 15) 175 g
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12) a metal alloy melts at 25°c. what is this temperature in °f? (3pts)…
12) $\boldsymbol{77\ \degree\text{F}}$ 13) $\boldsymbol{5.11\ \text{g/mL}}$
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2nh₃(g) + 3o₂(g) + ch₄(g) → 2hcn(g) + 6h₂o(g) considering the thermodyn…
A
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2nh₃(g) + 3o₂(g) + ch₄(g) → 2hcn(g) + 6h₂o(g) calculate the gibbs free …
\(-1107\)
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$$ce{p_{4}o_{10}(s) + 6h_{2}o(l) -> 4h_{3}po_{4}(aq)}$$considering the …
D
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6) which of the following is an example of a homogeneous mixture? (3pts…
$\square$ stainless steel
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p₄o₁₀(s) + 6h₂o(l) → 4h₃po₄(aq) calculate the gibbs free energy change …
-356
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4) your lab instructor gives you a red solid and tells you that it is a…
The solid has a fixed composition by mass.
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which statement is true for the reaction below?\\(\\ce{n2o4(g) -> 2no2(…
D. The reaction will occur only at high temperatures.
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3) the two types of pure substances are (3pts) compounds and elements. …
☑ compounds and elements.
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nameangelina emiren 2/2/26 write equations from verbal descriptions 1. …
\(y = \frac{1}{9}f\) ### Problem 2
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1) the distinction between law and theory as used by scientists is (3pt…
1. a law tells what happens, and a theory tells us why it happens. 2. phosphoric acid, $H_3PO_4$.
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calculate the standard entropy change for the combustion of propane, a …
-373
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which reaction results in a decrease in the entropy of the system? h₂o(…
A. \( \ce{H2O(g) -> H2O(l)} \)
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which reaction results in a negative δs? 2hgo(s)→2hg(l) + o₂(g) nacl(s)…
\(\boldsymbol{\text{H}_2\text{O}(l) ightarrow \text{H}_2\text{O}(s)}\) (the third option)
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calculate the standard reaction enthalpy for the reaction between no an…
-199
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calculate the standard enthalpy of formation, $delta h_{f}^{circ}$, of …
+50.8
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which of the reactions below is a formation reaction? ½n₂(g) + o₃(g) → …
6C(s, graphite) + 6H₂(g) + 3O₂(g) → C₆H₁₂O₆(s) (the fourth option)
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which of these could be part of the reactants in a formation reaction? …
\( \boldsymbol{P(s)} \) (since it is an element in its standard state, suitable as a reactant in a formation reaction)
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calculate the enthalpy for this reaction. h₂o + c → co + h₂ use the fol…
+131.5
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calculate the enthalpy for this reaction. mg + \\frac{1}{2}o_2 \ ightar…
\(-643\)
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part b underline the valence electrons. - $1s^2 2s^2 2p^6 3s^2 3p^6 4s^…
A. $1s^22s^22p^63s^23p^64s^23d^{10}\underline{4p^6}$
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add an ethyl substituent at carbon #3 to this organic molecule. be sure…
The skeletal structure with an ethyl substituent at carbon #3 is: ``` ── / ─C─C─C─C | ─ \ ── ``` (or in a more standard drawing: CH₃ / C₁─C₃─C₄ | C₂ \ CH₂ But in pure skeletal (li…
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calculate the percent by mass of $\\ce{k_{2}co_{3}}$ in a saturated sol…
\(\boxed{57\%}\) (or depending on graph reading precision, could be ~56% - 57%, but with two sig figs, 57% is appropriate)
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5. calculate the osmotic concentration (osmolarity) of a 0.5 m nacl sol…
1.0 Osm/L
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millions of years ago, tiny marine organisms died and sank to the ocean…
- Petroleum reservoirs are often found in sedimentary rocks that formed in ancient marine environments. - Petroleum is chemically similar to the remains of marine organisms like b…
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water drops or ice crystals. the tiny drops of water or ice crystals co…
Clouds form when water vapor condenses onto particles like dust to create droplets; moist, warm air rises because it is less dense than surrounding cooler air and continues to ris…
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questions do a, c, e 2. predict the electron configuration of each of t…
\( 1s^2 2s^2 2p^2 \) ### Question 2(c): Predict electron configuration of \( _7\text{N}^{3+} \)
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preparation before beginning the time study, complete the five question…
To solve for the number of protons, neutrons, and electrons in an atom, we use the following concepts: - **Protons**: Equal to the atomic number (\(Z\)) of the element. - **Electr…
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6. what is the most important type of physical weathering in high mount…
6. C. Frost wedging 8. D. Physical weathering
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5. frost wedging breaks rock apart because a.rocks contract when they b…
5. D. Water expands when it freezes 7. B. Breakdown 9. B. Its total surface area increases
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base your answers to questions 14 through 16 on the diagram of bowen’s …
1. El feldespato plagioclasio de la roca basáltica es rico en calcio y se forma a temperaturas altas, mientras que el de la roca granítica es rico en sodio y se forma a temperatur…
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part a choose the sketch of the mass spectrum of rhenium where the tota…
The second graph (with \(^{187}\text{Re}\) at 100% intensity and \(^{185}\text{Re}\) at ~60% intensity, labeled with the second radio button)
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3. sep analyze data calculate the ratio of the moles of product produce…
To solve this, we need the moles of product and moles of each reactant (let's assume a chemical reaction, say \( aA + bB ightarrow cC \), where \( A, B \) are reactants, \( C \) i…
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question 1 (2 points) read and complete each procedure step for lab 3, …
To solve this, you would first refer to your eScience Lab Manual, locate Table 1: Powder Mass, and then find the value listed for the total powder mass (in grams) from that table.…
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analyzing data proportional relationships in chemical reactions a chemi…
The table with changes is as above. For each trial: - Trial 1: \( N_2 \): 0.010, \( H_2 \): 0.030, \( NH_3 \): 0.020 - Trial 2: \( N_2 \): 0.070, \( H_2 \): 0.210, \( NH_3 \): 0.1…
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complete the sentences to explain the difference match the items in the…
1. Fluorine has $\boldsymbol{\text{one}}$ major isotope(s) corresponding to $\boldsymbol{\text{isotope F - 19}}$. Thus, the atomic mass of fluorine is equal to $\boldsymbol{\text{…
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two 20.0 g ice cubes at (-13.0) °c are placed into 245 g of water at 25…
$9.39^\circ\text{C}$
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lithium has only two naturally occurring isotopes. the mass of lithium …
7.5, 92.5
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do you expect the atomic mass of the element to be closer to that of is…
The average atomic mass will be closer to the mass of \(\boldsymbol{\text{isotope A}}\) because there is about \(\boldsymbol{\text{three}}\) times as much of \(\boldsymbol{\text{i…
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question 32 of 34 consider a hexagonal close - packed unit cell, as sho…
fraction inside the cell: $\frac{1}{2}$ number of atoms inside the cell: 6
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what kind of information can be determined from a mass spectrum? match …
1. The result of the mass spectrometer is the separation of the atoms in the sample according to their $\boldsymbol{\text{mass}}$, producing a $\boldsymbol{\text{mass spectrum}}$.…
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what is atomic mass? how is it calculated? match the items in the left …
- The atomic mass of an element represents: the average mass of the isotopes that compose that element, weighted according to the natural abundance of each isotope - It is calcula…
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how does the absorption of light provide heat energy in the ocean? tiny…
When light is absorbed, molecules vibrate and electromagnetic energy is converted to heat.
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which of the following has the highest residence time? chloride (cl-) c…
Iron (Fe)
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the solid phase of water is less dense than the liquid phase. true false
True
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water dissolves more substances than any other liquid; it is not a \uni…
True
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the latent heat of seawater is different than pure water due to the dis…
True
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the polarity of water makes it able to dissolve many compounds. true fa…
True
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water has the highest specific heat of any liquid except ammonia. t/f
T
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chemistry lab and classroom worksheet answer the following questions on…
- Read the experiment’s instructions thoroughly. - Wear proper PPE (lab coat, goggles, gloves, closed - toe shoes). - Inspect all lab equipment for damage. - Organize and clear th…
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what is the average ph of the ocean? 7.5 8.1 7.0 8.7
B. 8.1
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1. classify each of the following elements as metal, non metal or metal…
- K: Metal - Xe: Non - metal - Ge: Metalloid - Pu: Metal - Ni: Metal - Kr: Non - metal ### Question 2
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which of the following statements is not correct? a calorie is the amou…
B. It takes more heat to melt one gram of ice than it does to boil one gram of water to water vapor
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which are the two most common ions in seawater are? bicarbonate (hco3-)…
D. chloride (Cl⁻) & sodium (Na⁺)
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b. mining and clear cutting in the canadian shield canadas mining indus…
Three valuable natural resources in the Canadian Shield are gold, silver, and timber (or any three from gold, silver, copper, zinc, lead, iron ore, uranium, nickel, or timber-rela…
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question 3 (4 points) why is it important to blend the powders using th…
The "doubling" (geometric dilution) technique ensures uniform blending, especially when ingredient quantities differ greatly. Blending all at once risks uneven distribution (segre…
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question 6 (4 points) what kind of mortar and pestle is most ideal for …
The most ideal mortar and pestle for many laboratory grinding procedures is Wedgewood (often agate - based Wedgewood - type). It is ideal because it is extremely hard and chemical…
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youve been asked to stabilize a compound whose general state is altered…
An alkali metal (e.g., Sodium, Na) Why? Alkali metals are highly electropositive, readily donating their single valence electron to neutralize the excess electrons in the compound…
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question 5 (4 points) what purpose does the sieve serve after triturati…
After trituration, a sieve serves to separate particles by size: it allows properly ground (small - sized) particles to pass through its openings while retaining larger, insuffici…
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one of us is lying chapter 8 bronwyn 1. true or false. after the funera…
Bronwyn shares that she got a B on her chemistry test (not the A+ her parents expected) and that she has been struggling with chemistry. ### Question 3
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capacity before moving on. - electrons on the outer most ring are known…
a. Element = Carbon (C); Valence Electrons = 4 b. Element = Phosphorus (P); Valence Electrons = 5 c. Element = Argon (Ar); Valence Electrons = 8 --- a. Nitrogen (N): Valence Elect…
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capacity before moving on. - electrons on the outer most ring are known…
### Problem 22 (assuming we analyze part a first, and we'll follow the same logic for b and c) #### Part a: # Explanation: ## Step 1: Count total electrons (protons = electrons in…
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2naoh + h₂so₄ → 2h₂o + na₂so₄ 50.0 ml of 0.50 m h₂so₄ is added to 60.0 …
\(-24.33\) (or more precisely, if we calculate \(\frac{-584\space J}{0.024\space mol}=\frac{-0.584\space kJ}{0.024\space mol}\approx - 24.33\space kJ/mol\))
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hcl + naoh → nacl + h₂o 25.0 ml of 1.00 m hcl is added to 75.0 ml of 1.…
-148.4 (or -148 if rounded, but the precise calculation gives -148.4)
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the combustion of 4.00 grams of milk in a bomb calorimeter resulted in …
\(248\) (or approximately \(247.9\)) \(J/^{\circ}C\) (If we calculate more precisely \(\frac{843}{3.4}=247.941176\cdots\), so we can present it as \(248\) or \(247.9\) depending o…