化學
化學反應、化學計量、分子結構與元素性質。
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why do water molecules form crystalline lattice structures when water f…
The correct option is: "Like charges repel and opposite charges attract. This way the oxygen will be far away from each other since they are like charges." ### Question 12 (chemic…
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the freeze thaw action of weathering is due to waters different densiti…
True ### Question 10 (Why ice is less dense than water)
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what is the best explanation for why the stream of water was attracted …
The uneven distribution of the electrons in the water molecule are attracted to the charged balloon. ### Question 6 (Property of water dissolving many substances)
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why do oil and water separate after being mixed? - water and oil are bo…
C. Water is polar and oil is non - polar. The attraction between polar molecules and non - polar molecules are not strong enough to mix. ### Second Question (What would happen if …
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how does water shape the earth? choose all that apply. □ by transportin…
- By transporting the products of weathering to other places. - By mechanically shaping rocks by flowing over or by frost wedging. - By dissolving minerals of rocks. - By directly…
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naming acids name the following acids. 1. hno₃ 2. hcl 3. h₂so₄ 4. h₂so₃…
1. Nitric acid 2. Hydrochloric acid 3. Sulfuric acid 4. Sulfurous acid 5. Acetic acid 6. Hydrobromic acid 7. Nitrous acid 8. Phosphoric acid 9. Hydrosulfuric acid 10. Carbonic aci…
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(1 point) co₂ nacl h₂o polar covalent ionic nonpolar covalent
\(CO_2\) - nonpolar covalent; \(NaCl\) - ionic; \(H_2O\) - polar covalent
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no₂⁻ nitrogen and oxygen have an electronegativity difference of △, so …
Electronegativity difference: \( 0.5 \); Bond type: polar covalent; Electron puller: oxygen (O); Oxygen charge: negative; Nitrogen charge: positive
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select the correct values to balance the equation: (1 point) 4nacl + 2s…
The coefficient of \( H_2O \) is 2, the coefficient of \( O_2 \) is 1, and the coefficient of \( Na_2SO_4 \) is 2. So the balanced equation is \( 4NaCl + 2SO_2 + 2H_2O + 1O_2 ight…
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use your knowledge of valence electrons and bond formation to complete …
The carbon atom shares \(\boldsymbol{\text{one pair of electrons}}\) (or "one electron pair") with each Hydrogen atom, forming \(\boldsymbol{\text{a single covalent bond}}\) (or "…
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use your knowledge of valence electrons and bond formation to complete …
1. The first dropdown (compound type): covalent molecule 2. The second dropdown (what carbon shares with each H): 1 electron (or "a pair of electrons" – but based on valence elect…
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use your knowledge of valence electrons and bond formation to complete …
First dropdown: Hydrogen Second dropdown: Methane Third dropdown: one pair of electrons Fourth dropdown: a single covalent bond
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use the reaction to answer the question. zn + 2hcl → zncl₂ + h₂ what ty…
C. replacement
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not all atoms can be bonded together at random and form stable configur…
- MgO (stable) - PH₃ (stable) - CaBr (unstable) - NaF₂ (unstable) So the stable molecules are MgO and PH₃. The checkboxes for MgO and PH₃ should be selected.
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use the equation below to answer the question: ch₄ + 2o₂ → co₂ + 2h₂o i…
There are now 4 molecules of \( H_2O \) (the first option: "There are now 4 molecules of \( H_2O \)")
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what is the balanced equation for the reaction of iron and oxygen gas s…
A. \(4\text{Fe} + 3\text{O}_2 \to 2\text{Fe}_2\text{O}_3\)
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which property of an atom is related to its ability to attract electron…
C. Electronegativity
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what is the correct coefficient for oxygen (o₂) to balance the followin…
6 (corresponding to the option with 6)
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the element bromine (br) has 7 valence electrons. which of the followin…
A. One atom of Lithium, which has one valence electron
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in a chemical reaction, if two elements have similar electronegativitie…
B. Covalent bond
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15) how many grams are in 4.5 moles of sodium fluoride, naf? 16) how ma…
Approximately 189 grams (or 188.96 g) ### Question 16: How many moles are in 98.3 grams of aluminum hydroxide, $\text{Al(OH)}_3$?
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select the correct answer what is one way that historians can establish…
A. by comparing the source to other established sources from that time period
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the temperature at 300 seconds (5 minutes) is the final temperature of …
25.0
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mass and the mole 1) how many moles are in 15 grams of lithium? 2) how …
Approximately \( 2.16 \) moles. ### Problem 2: How many grams are in 2.4 moles of sulfur?
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an element with mass 730 grams decays by 28.8% per minute. how much of …
22.0
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question 12 (5 points) which of these alcohols is often called wood alc…
C) Methanol ### Question 13
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a chemistry student in lab needs to fill a temperature - control tank w…
5.96 L
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a chemistry grad student measures the performance z of the new pump in …
$18.7$
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a chemistry grad student measures the performance z of the new pump in …
$9.4 \times 10^{-3}$
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please note: leaving this page before submitting your assessment will r…
a) True
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reconstructing a landscape which statements about this area are true ba…
- The area was once a forest. - The area was uplifted. - The area was probably covered by water.
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question 23 (1 point) which of the following is the electron configurat…
d) \(\frac{\uparrow\downarrow}{2s}\ \frac{\uparrow\downarrow}{2p}\ \frac{\uparrow}{}\ \frac{\uparrow}{}\)
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which of the following is the electron configuration for calcium, ca? a…
a) \(1s^22s^22p^63s^23p^64s^2\)
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question 21 (1 point) use the following information to answer the next …
d) -0.5 KCal
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question 20 (1 point) the amount of heat evolved or absorbed during che…
b) Changes in heats of reaction
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instructions for the following reaction, assume cucl₂ and agno₃ complet…
Question 4: 6 Question 5: 12
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3 numeric 1 point calculate, in kj, the $\\delta h_{rxn}$ for the follo…
$-908\ \text{kJ}$
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bond enthalpies (kj/mol) h–h 432; n–h 391; i–i 149; c=c 614 h–f 565; n–…
$\boldsymbol{-1304}$ kJ/mol
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1. formula 1 point $2\\ce{c6h14(l)} + 19\\ce{o2(g)} \ ightarrow 12\\ce{…
The energy change (released) is approximately $\boldsymbol{1980\ \text{kJ}}$ (or $\boldsymbol{-1980\ \text{kJ}}$ if sign denotes direction, negative for exothermic)
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the correct structure for 1 - methyl - 2,4,6 - trinitrobenzene(tnt) is …
b) The structure with a $\ce{CH_3}$ group and $\ce{NO_2}$ groups at positions corresponding to 1 - methyl - 2,4,6 - trinitrobenzene.
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question 15 (1 point) alkanes react with halogens in an addition reacti…
False
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question 14 (1 point) the compound above is classified as a(n) a) aldeh…
a) aldehyde
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question 13 (1 point) the correct iupac name for the compound above is …
b) 4 - ethoxypentanal
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question 12 (1 point) examine the figure below for the following questi…
b) B
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question 12 (1 point) examine the figure below for the following questi…
b) B
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question 10 (1 point) if the rate law for a hypothetical reaction is $r…
b) first
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which of the following is true of iron? a. it has the highest electrica…
B. It can exist in many alloys, usually with a carbon base.
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question 9 (1 point) a system has reached chemical equilibrium. which i…
a) there is no net change in the concentration of reactants or products
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question 8 (1 point) which is true of the numerical value of the equili…
a) It represents the relative concentration of products compared with reactants.
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question 7 (1 point) if $q_{eq} > k_{eq}$, then ______. a) the ratio of…
b) the ratio of products to reactants is greater than \(K_{eq}\)
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question 6 (1 point) use the following information to answer the next q…
c) \( K_{\text{eq}} = \frac{[\ce{ClO_3^-}]^2 [\ce{Cl^-}]}{[\ce{ClO_2^-}]^3} \)
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a chemistry student in lab needs to fill a temperature - control tank w…
2.31
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question 5 (1 point) which of these affects the equilibrium constant, $…
d) temperature
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question 4 (1 point) how many hydrogen ions must be added to the half r…
e) 4 on the left side
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question 3 (1 point) identify the reducing agent in the reaction: $\\ce…
b) \( \text{Sn}^{2+}(\text{aq}) \)
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question 2 (1 point) in the reaction: $\\ce{kno_{3}(aq) + pbso_{4}(aq) …
e) there is no reducing agent
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question 1 (1 point) what is the correct balanced redox reaction for $m…
e) \( 3\text{Zn}^{2+}(aq) + 2\text{Al}(s) ightarrow 3\text{Zn}(s) + 2\text{Al}^{3+}(aq) \)
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oxygen is acting as an oxidizing agent in all of the following reaction…
C. \( 2F_2(g) + O_2(g) ightarrow 2OF_2(g) \)
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6. the chemical weathering of feldspar produces ______. ○ quartz grains…
B. clay minerals
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5. the most important agent of chemical weathering is carbonic acid nit…
C. water
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how do wetlands help maintain good water quality? 1. 2. 3. 4. 5. 6. tru…
s (for the numbered list): 1. Trap sediments from runoff to improve clarity. 2. Absorb excess nutrients to prevent eutrophication. 3. Host microbes that break down organic polluta…
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which is an example of chemical weathering? a. explosives breaking apar…
C. acid rain changing granite into clay minerals and quartz grains
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molecular representation of a wildfire balanced chemical equation of a …
The balanced equation is \( \boldsymbol{\ce{C6H12O6 + 6O2 -> 6CO2 + 6H2O}} \) with coefficients 1, 6, 6, 6 (for \( \ce{C6H12O6} \), \( \ce{O2} \), \( \ce{CO2} \), \( \ce{H2O} \) r…
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instructions: draw and label the following structures on the next page:…
- Glucose: Draw 1 molecule (using the given structure). - Oxygen: Draw 6 \(O=O\) molecules. - Carbon Dioxide: Draw 6 \(O=C=O\) molecules. - Water: Draw 6 \(H-O-H\) molecules. - Ma…
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name alisson serrano pd. 4 date 1-16-26 wildfires final project - symbo…
\( \boldsymbol{1} \) \( \ce{C6H12O6} \) + \( \boldsymbol{6} \) \( \ce{O2} \) \( \boldsymbol{ ightarrow} \) \( \boldsymbol{6} \) \( \ce{CO2} \) + \( \boldsymbol{6} \) \( \ce{H2O} \)
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background engage: making sense of milk in this activity, you will wond…
1. a. Water, lactose, fats, casein, calcium, vitamins b. Scattered light from proteins/fat globules c. Particles scatter all visible light wavelengths d. No; varies by animal/proc…
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4) check if each statement describes an alkali metal, an alkaline earth…
### Part 4) Checkbox Matches: | Statement | Transition Metal | Alkali Metal | Alkaline Earth Metal | |-----------|------------------|--------------|----------------------| | inclu…
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10) drag and drop the answers for the orbital diagram for nitrogen. ref…
1s: $\boldsymbol{\uparrow\downarrow}$ 2s: $\boldsymbol{\uparrow\downarrow}$ 2p: $\boldsymbol{\uparrow}$ $\boldsymbol{\uparrow}$ $\boldsymbol{\uparrow}$ 3s: (empty) 3p: (empty)
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13) choose all that apply. refer to the periodic table. what sublevels …
□ p □ d □ s $\square$ f
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15) choose the best answer. refer to the periodic table. what is the el…
## Question 15: $\boldsymbol{1s^22s^22p^63s^23p^64s^23d^{10}4p^2}$ ## Question 16: $\boldsymbol{[Ar] 4s^23d^{10}4p^2}$
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17) choose the correct electron configuration for the element. refer to…
17. $1s^2$ 18. $[Xe] 6s^24f^{14}5d^{10}6p^4$
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19) choose the correct electron configuration for the element. refer to…
19) [Ar] 4s²3d¹⁰ 20) [Ar] 4s²3d⁶
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what is the electron configuration for nitrogen? 1s²2s²2p³ 1s²2s²2p⁶3s²…
1. Multiple choice answer: $\boldsymbol{1s^22s^22p^3}$ 2. How many electrons does germanium have? $\boldsymbol{32}$ 3. What period is germanium in? $\boldsymbol{4}$ 4. How many en…
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9) choose all that apply. refer to the periodic table. what two subleve…
□ s □ p
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8) type the correct answers in the blanks. refer to the periodic table.…
8) - How many electrons does nitrogen have? 7 - What period is nitrogen in? 2 - How many energy levels does nitrogen have? 2 9) - $\square$ s - $\square$ p - $\square$ f - $\squar…
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7) drag and drop the electron configurations to the elements. refer to …
- $1s^22s^22p^63s^23p^5$ → Cl - $1s^22s^22p^3$ → N - $1s^22s^22p^63s^23p^1$ → Al - $1s^22s^22p^63s^23p^64s^23d^{10}$ → Zn
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5) choose the best answer. which of these elements can be used to write…
5. Ar 6. atomic number
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3) choose the best answer. which rule states that orbitals of equal ene…
3. B. Hund's rule 4. B. Pauli exclusion principle
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1) choose the best answer. what is electron configuration? the outermos…
1. the arrangement of electrons in an atom 2. Aufbau principle
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evaluation continue n°1 de physique chimie coef: 3 la qualité de la réd…
### Partie I : Physique (Questions de cours) #### 1. Définitions - **Force** : Action capable de modifier l'état de mouvement (vitesse, direction) ou la forme d'un objet. - **Dyna…
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7. which of the following statements describes the term concentration? …
d. Two of the above describe the term concentration. ### Question 8
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chemistry 11 sch3u test 4 – solutions and solubility name:_____________…
a. \( \text{Ca(OH)}_{2(\text{s})} ightarrow \text{Ca}^{2+}_{(\text{aq})} + 2\text{OH}^-_{(\text{aq})} \) ### Question 2
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14) choose the best answer. (see companion material, the periodical tab…
14) D. 14 15) B. Ca
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11) choose the best answer. (see companion material, the periodical tab…
11. Co 12. Nd 13. 5
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9) choose the best answer. which sublevels are found in the 4th energy …
9. s, p, d, and f 10. a. 2 b. 8 c. 18 d. 32
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7) choose the best answer. how do you determine the number of energy le…
7. It is the same number as the period number. 8. 7
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3) choose the best answer using a periodic table. (see companion materi…
The third option (the structure with 7 dots around the Cl symbol: 2 dots top, 2 dots right, 2 dots bottom, 1 dot left)
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1) choose the best answer. elements in a group have similar properties …
1. valence electrons 2. It is the same number as the last digit of the group number.
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oxygen is acting as an oxidizing agent in all of the following reaction…
C. \(2 \text{F}_2(\text{g}) + \text{O}_2(\text{g}) ightarrow 2 \text{OF}_2(\text{g})\)
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oxygen is acting as an oxidizing agent in all of the following reaction…
C. \(2 F_2(g) + O_2(g) ightarrow 2 OF_2(g)\)
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oxygen is acting as an oxidizing agent in all of the following reaction…
C. \( \ce{2F2(g) + O2(g) -> 2OF2(g)} \)
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oxygen is acting as an oxidizing agent in all of the following reaction…
C. \( \ce{2 F2(g) + O2(g) → 2 OF2(g)} \)
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oxygen is acting as an oxidizing agent in all of the following reaction…
C. \( \ce{2 F2(g) + O2(g) → 2 OF2(g)} \)
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oxygen is acting as an oxidizing agent in all of the following reaction…
C. \( 2 F_2(g) + O_2(g) ightarrow 2 OF_2(g) \)
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oxygen is acting as an oxidizing agent in all of the following reaction…
C. $\boldsymbol{2F_2(g) + O_2(g) ightarrow 2OF_2(g)}$
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oxygen is acting as an oxidizing agent in all of the following reaction…
C. \(2 F_2(g) + O_2(g) ightarrow 2 OF_2(g)\)
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1. what are the four major sources of energy harnessed by engines? 2. e…
The four major sources of energy harnessed by engines are typically chemical energy (from fuels like gasoline, diesel, coal, etc.), thermal energy (heat, e.g., from steam), mechan…
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practice: 1. read the following scales. record the correct number of di…
First Thermometer: $45.7^\circ \text{C}$ Second Thermometer: $21.0^\circ \text{C}$ (or $21.05^\circ \text{C}$ if the divisions are 0.05, but likely 21.0) Third Thermometer: $100.1…
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crystals 6. what are crystals? crystals are solid materi arranged in a …
Crystals are solid materials in which atoms, molecules, or ions are arranged in a highly ordered, repeating three - dimensional lattice structure.
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what volume in liters of a 0.724 m nai solution contains 0.405 mol of n…
0.559 liters (Factor setup for the diagram: Starting amount: \( 0.405 \) mol NaI Multiplication factor: \( \frac{1\ \text{L}}{0.724\ \text{mol NaI}} \))