Chemistry
Chemical reactions, stoichiometry, molecular structures, and element properties.
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2. for the following pair of substances (i) and (ii) state which would …
The pair (i) (3g of salt in 1M HCl) has a higher reaction rate. This is because the concentration of the hydrochloric acid (1M) is higher than in (ii) (0.1M), and reaction rate in…
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the following pair of substances (i) and (ii) state which would have a …
The reaction (dissolution of salt or reaction with HCl) will have a higher rate in the solution of 1M hydrochloric acid. The factor affecting the rate is concentration. A higher c…
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1. use the diagram to the right to answer the following question: /4 a)…
Endothermic ### Part (b)
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name molar mass maze directions: begin on the start square and calculat…
To solve the Molar Mass Maze, we start at the "START" block and calculate the molar mass of each compound, following the correct path to the "FINISH". Here are the key calculation…
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what is the percent composition of elements in caffeine c₈h₁₀n₄o₂? perc…
### Percent Composition & Formulas 1. Percent composition of caffeine: - Carbon: 49.47% - Hydrogen: 5.19% - Nitrogen: 28.86% - Oxygen: 16.48% 2. Empirical formula: $\text{C}_3\tex…
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12. calculate the number of moles of molecules in $1.20 \\times 10^{24}…
The number of moles is approximately $\boldsymbol{2.00}$ mol (or $\boldsymbol{1.99}$ mol for more precision).
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Question was provided via image upload.
$$1\text{CH}_4 + 2\text{O}_2 ightarrow 1\text{CO}_2 + 2\text{H}_2\text{O}$$ (The coefficients in order are: 1, 2, 1, 2)
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10. for a first order reaction, a plot of which variables will result i…
b. \(\ln[A]\) vs time
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e. the frequency of collisions possessing kinetic energy exceeding the …
c. Increase by a factor of 4
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overall rate concentration of a reactant not involved in the rds will s…
d. A greater fraction of collisions possess kinetic energy exceeding the activation energy
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7. which statement regarding the rate determining step (rds) of a multi…
d. The rate law of the overall reaction is identical to the rate law of the RDS
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4. balance the following reactions: \\(\\ce{albr_{3} + k_{2}so_{4} \ ig…
$2\text{AlBr}_3 + 3\text{K}_2\text{SO}_4 ightarrow 6\text{KBr} + \text{Al}_2(\text{SO}_4)_3$
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chemistry i – introduction to lewis structures for more complicated mol…
To solve for the Lewis structures of each compound, we follow the 5 - step procedure for Lewis structures: ### 1. For \( \boldsymbol{HCl} \) - **Step 1: Determine total valence el…
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c. $e_{a(\text{reverse})} = e_{a(\text{forward})}$ d. $e_{\text{reverse…
c. \(0.41\ J/g\cdot^{\circ}C\)
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4. how does the activation energy (ea) of the reverse reaction relate t…
a. \( E_{\text{reverse}} = E_{\text{forward}} - \Delta H \)
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3. which of the following statements about specific heat capacity is in…
d. A bath tub of water would have a lower heat capacity than a teaspoon of water
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2. for the reaction \\(\\ce{n_{2(g)} + 3h_{2(g)} -> 2nh_{3(g)}}\\), the…
To solve this, we analyze each statement using bond energy and enthalpy concepts: ### Step 1: Recall reaction enthalpy formula Reaction enthalpy ($\Delta H$) = Sum of bond energie…
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elements and the periodic table- reading comprehension directions: answ…
**: matter 2. **Explanation for Q2**: John Dalton’s atomic theory is known as Dalton’s Atomic Theory.
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read the lab report conclusion and then answer the question. based on t…
B. a high school science teacher
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their home, grazing 1 in aroostook county, northern maine, i knew nothi…
4. The stove is the central feature of the room.
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***please indicate your choice in the box like this: a) b) c) d) e) 1. …
To solve this problem, we need to determine the enthalpy change of the dissolution process. This involves calculating the heat absorbed by the solution (since the temperature drop…
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1 in aroostook county, northern maine, i knew nothing about fiddleheads…
4. a sense that the room is the same as it has been for years
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name: zach lewis (electron dot) diagrams worksheet - review 1. draw lew…
## 1. Single-Atom Lewis Diagrams: - $\text{Li} \cdot$ - $\cdot \ddot{\text{F}} :$ - $\cdot \ddot{\text{Si}} \cdot$ $\quad \cdot$ - $\cdot \ddot{\text{N}} :$ $\quad \cdot$ - $\text…
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examples of the chemical energy mention in the video are coal, petroleu…
B. Batteries, burning gasoline and fireworks
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chemical energy is the energy of ______ reactions. chemical physical re…
chemical
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do now 20 (module 7 - lesson 4) 3 of 4 01:38 / 05:00 possible points: 2…
H-H < H-C < H-N < H-O < H-F
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read the poem \to a much too unfortunate lady.\ he will love you presen…
Please clarify your question about the poem (e.g., theme, literary devices, rhyme scheme) to get a specific answer.
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8) if the mass of a rock is 23.8 g and the volume of that rock is 4.51 …
D. 5.28 g/mL
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7) how much water (in ml) is in this graduated cylinder? a) 6 ml b) 6.6…
C) 6.6 mL ### Question 8
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a compound is formed in the reaction below: $6h_2o + 6co_2 \ ightarrow …
- Mass of \(CO_2\) used: 144.12 g (the option is 144.12) - For \(NH_4\) - match with 5 is correct; for \(HC_2H_3O_2\) - match with 8 is correct. - Moles of Carbon: 3 (the option i…
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match the term to whether it is endothermic or exothermic. * 6 points e…
s: #### Phase Changes (Correct Selections): - Boiling: Endothermic (correct as marked). - Condensing: Exothermic. - Deposition: Exothermic. - Evaporating/Vaporating: Endothermic (…
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beaker a beaker b which beaker will require more energy to change the t…
**C:** Beaker B needs more energy for temp change. **E:** Beaker A = 800 mL; Beaker B = 1000 mL. **R:** $Q=mc\Delta T$; higher mass needs more $Q$.
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how are elements represented on the periodic table? periodic table of t…
C. By chemical symbols
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which sample of water contains particles having the highest average kin…
A. 25 mL of water at 95°C ### Second Question (Kelvin Difference Between Boiling and Freezing Points)
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question 25 of 25 which of the following has the largest radius? a. k b…
A. K
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question 24 of 25 how can the number of core electrons be determined fr…
D. By finding the atomic number minus the group number
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question 22 of 25 how many oxygen atoms are in a molecule of table suga…
D. 11
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question 20 of 25 what is the correct electron configuration for an ele…
D. \(1s^22s^22p^63s^23p^3\)
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question 19 of 25 which of the following is the correct name for $\\ce{…
B. Chromium(III) oxide
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question 18 of 25 what is a molecular dipole moment? a. the arrangement…
B. A separation of charge forming a positive and a negative end of a molecule
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question 17 of 25 which electrons in an atom have the highest energy? a…
C. The valence electrons
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question 16 of 25 which term describes this molecular shape? x - a - x …
C. Trigonal planar
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question 15 of 25 how does a lone pair distort the molecular shape? a. …
C. The lone pair forces bonding atoms away from itself.
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question 13 of 25 which sentence describes two atoms that form an ionic…
C. The difference in their electronegativities is greater than 1.7.
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question 12 of 25 in which situation would dipole-dipole forces be sign…
B. When molecules have permanent dipole moments
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what does the vsepr theory predict? a. the size of a molecule b. the ch…
C. The shape of a molecule
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question 10 of 25 which of these elements has the smallest first ioniza…
C. Rb
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question 10 of 25 which of these elements has the smallest first ioniza…
C. Rb
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question 9 of 25 what happens to the atomic radius when an electron is …
A. The positive ionic radius is smaller than the neutral atomic radius.
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question 8 of 25 which sentence describes the bond formed between two i…
D. The electrons involved in the bond are shared equally between the atoms.
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3.5.2 test (cs1): computer-scored unit test which h₂s molecules dipole …
B. \( \boldsymbol{\delta^+}\ce{H - \overset{\delta^-}{S} - H^{\delta^+}} \) with the dipole moment arrow pointing upward (toward S)
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question 6 of 25 why are prefixes used in naming covalent compounds? a.…
C. The same atoms can combine in more than one ratio.
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question 5 of 25 how many total electrons can the d orbitals hold? a. 1…
A. 10
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question 4 of 25 which of the following is a binary compound? a. cao b.…
A. $\ce{CaO}$
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question 3 of 25 in which situation would hydrogen bonding be present? …
C. When hydrogen is attached to N, F, or O
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question 2 of 25 which molecule or ion has a linear shape? a. becl₂ b. …
A. \( \text{BeCl}_2 \)
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question 1 of 25 what is the general trend in electronegativity as you …
D. Electronegativity increases.
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when food is exposed to air, it can lose electrons. this loss of electr…
B. Free radicals
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question 10 of 10 how are prefixes used to name compounds? a. prefixes …
C. Prefixes are used to tell how many of each kind of atom are in covalent compounds.
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question 9 of 10 which of the following is the correct name for $\\ce{n…
C. Dinitrogen pentasulfide
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question 7 of 10 what is used to determine the number of each atom in a…
D. The oxidation state of each atom
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question 6 of 10 which of the following is the correct formula for sili…
D. $\ce{SiO_2}$
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question 5 of 10 why are prefixes not used in naming ionic compounds? a…
C. Two ions can combine in only one combination.
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question 4 of 10 which of the following is the correct formula for alum…
A. $Al_2O_3$
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question 3 of 10 what is the most likely oxidation state of nitrogen? a…
A. -3
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which of the following is the correct name for bacl₂? a. monobarium dic…
C. Barium chloride
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question 10 of 10 what shape would a molecule with two bound groups and…
B. Bent
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question 9 of 10 if there were only three electron groups around an ato…
D. They would be arranged in a trigonal planar orientation.
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question 8 of 10 what is a lone pair? a. two pairs of electrons that fo…
D. A pair of electrons that is not used in bonding
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question 7 of 10 how does the shape of a molecule affect the polarity o…
A. A molecule that has a symmetrical shape will be a nonpolar molecule.
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if two atoms are bonded to a central atom with no lone pairs, how will …
B. In a linear shape
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question 5 of 10 which of the following molecules has a trigonal pyrami…
D. $\ce{XeO_3}$ (the molecule with central Xe and three O atoms attached)
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question 4 of 10 what is a consequence of electron - pair repulsion aro…
C. The atoms sharing the electron pairs will spread out around the central atom.
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question 3 of 10 how does the shape of a molecule affect its function? …
A. The shape of a molecule determines its properties and interactions.
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what does the vsepr theory describe? a. how atomic radii change during …
D. Why molecules have different shapes
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question 1 of 10 what would cause the shape of a molecule to be tetrahe…
B. Four atoms bound to a central atom with no lone pairs
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question 10 of 10 what do van der waals forces do? a. they stimulate hy…
D. They form temporary, weak dipole attractions between molecules.
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question 9 of 10 which of the following interactions is not a type of i…
B. Covalent bonds
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question 8 of 10 what do dipole-dipole forces do? a. hold nonpolar mole…
C. Hold polar molecules together
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question 7 of 10 what kind of bonds are hydrogen bonds? a. an intramole…
C. Strong polar attractions between molecules involving H, F, O, and N
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question 6 of 10 which of these molecules has an overall dipole moment?…
C. \( \text{H}_2\text{S} \)
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question 5 of 10 which of the following is a result of intermolecular f…
B. Hydrogen bonds
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question 4 of 10 how does molecular shape affect polarity? a. if the mo…
A. If the molecule is symmetrical, the effects of polarity will cancel out.
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question 3 of 10 what kind of covalent bond involves an even sharing of…
B. A nonpolar covalent bond
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question 2 of 10 what does the presence of a polar covalent bond show a…
D. The electronegativities of the two atoms are not equal.
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question 1 of 10 which of the following molecules contains a nonpolar c…
A. $H_2$
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question 10 of 10 what kind of bond would many atoms of the same metal …
C. A metallic bond
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question 9 of 10 what kind of bond is present in nabr? a. hydrogen bond…
D. Ionic bond
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question 8 of 10 why do noble gases rarely form bonds with other atoms?…
C. The noble gases are already stable, with full octets of valence electrons.
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question 7 of 10 which of the following values best classifies a bond b…
C. An electronegativity difference of less than 1.7 between the atoms
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question 6 of 10 what is a triple bond? a. a covalent bond between 2 at…
B. A covalent bond between 2 atoms where each atom contributes 3 electrons
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question 5 of 10 which of the following diagrams is the correct electro…
B. $\boxed{:\stackrel{..}{Ne}:}$ (or as per the diagram in option B: the diagram with 8 dots around Ne, 2 on each side)
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question 4 of 10 which of the following examples is a molecule with a c…
A. CO
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question 3 of 10 what is an ionic bond? a. a bond formed from 2 atoms o…
B. A bond resulting from the transfer of 1 or more electrons
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question 2 of 10 which two atoms would typically form a covalent bond? …
D. Two atoms that are both nonmetals
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question 10 of 10 which of the following elements has the lowest first …
B. Strontium (Sr)
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question 9 of 10 what makes the atomic radius change down a column of t…
C. The larger the highest energy level number, the larger the atomic radius.
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question 8 of 10 the periodic trend for electronegativity is similar to…
D. The trend for first ionization energy
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question 5 of 10 what is a periodic trend? a. any characteristic of the…
B. A pattern that appears on the periodic table
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question 4 of 10 why do nonmetals tend to gain electrons to form negati…
D. They gain the few electrons they need to form full octets.