化学
化学反応、化学量論、分子構造、元素の性質。
-
4. calculate the percent composition of the elements in cas.
Percent composition of Ca: ~55.55%, Percent composition of S: ~44.45%
-
3. find the percent composition of both elements in hbr.
Percent composition of H ≈ 1.25%, Br ≈ 98.75%
-
a quantity of $2.00 \\times 10^2$ ml of 0.862 m hcl is mixed with an eq…
\( 26.7^\circ C \) (or \( 26.70^\circ C \) with proper sig figs)
-
exam 4 part 1 question 6 of 13 (1 point) | question attempt: 1 of 1 a p…
\(0.237\)
-
8. what is the mass of 2.05 moles of gallium (iii) sulfide (ga₂s₃)? 9. …
Approximately $\boldsymbol{483\ \text{g}}$ (or as per precise calculation, ~483.06 g) ### Problem 9: Molecules in 368 g of potassium hydroxide ($\ce{KOH}$)
-
consider the following data: | metal | mass (g) | specific heat \\(\\le…
Heat will flow from Cu to Pb because Cu is at a higher temperature.
-
b. according to statistics, do most teens abuse drugs? a. yes b. no 2. …
1.b: B. No 2.a: B. They interact with the neurochemistry of the brain to produce feelings of pleasure 2.b: A. Yes, it differs by the type of drug and how it is used
-
consider the following decomposition reaction: 2 hbr(g) + 72.4 kj → h₂(…
\(1.27\times10^{5}\)
-
2. determine the percent composition of each element in alcl₃.
Percent composition of Al: ~20.24%, Percent composition of Cl: ~79.76%
-
% element = (mass of element in formula / molar mass of compound) × 100…
1. %Mg ≈ 60.3%, %O ≈ 39.7% 2. %Al ≈ 20.2%, %Cl ≈ 79.8% (assuming AlCl₃)
-
calculate the amount of heat absorbed when 0.540 moles of chlorine are …
\( 131 \) (or value based on specific reaction's ΔH, e.g., if ΔH = 242 kJ/mol, the answer is \( 131\ \text{kJ} \))
-
type coefficients in each blank to balance the chemical equations below…
\(2Al + 6HCl ightarrow 3H_2+2AlCl_3\) \(2NaF + 1Br_2 ightarrow 2NaBr+1F_2\) \(2Al + 3FeO ightarrow 1Al_2O_3+3Fe\)
-
consider the following thermochemical reaction: i₂(s) + cl₂(g) + 54.0 k…
A. endothermic
-
directions: show all work for full credit and circle final answers. use…
% Mg ≈ 60.3%, % O ≈ 39.7%
-
directions: show all work for full credit and circle final answers. use…
1. % Mg ≈ 60.3%, % O ≈ 39.7% 2. % Al ≈ 20.3%, % Cl ≈ 79.7%
-
balance the chemical equation below, then use the objects in the answer…
\(4Na+O_2 ightarrow2Na_2O\)
-
identify the endothermic processes. check all that apply. mg(s) + 2 h₂o…
The endothermic processes are: - $2\ce{HBr}(g) + 72.4$ kJ $ ightarrow \ce{H2}(g) + \ce{Br2}(l)$ - $\ce{H2}(g) + \ce{I2}(s) + 53.$ kJ $ ightarrow 2\ce{HI}(g)$ - $\ce{H2SO4}(l) + 13…
-
identify the exothermic processes. check all that apply. mg(s) + 2h₂o(l…
- \( \ce{Mg(s) + 2H2O(l) -> Mg(OH)2(s) + H2(g)} \), \(\Delta H = -84.3\) kcal - \( \ce{N2O5(g) + H2O(l) -> 2HNO3(l)} \), \(\Delta H = -18.1\) kcal
-
2. (a) draw a model bohr diagram for lithium in the space provided. (b)…
Losing its valence electron (or “losing an electron”). ### 2. (c) Charge of Lithium Ion
-
reflection questions 1. what can experiments in a lab tell us about sub…
Lab experiments can help us understand the physical and chemical properties of substances that may exist on Titan. By recreating conditions similar to Titan's environment (such as…
-
balance the chemical equation below, then use the objects in the answer…
\(2Ni_2O_3 ightarrow4Ni + 3O_2\)
-
the universal space agency wants to know the results of your sim invest…
The phenomenon occurs due to condensation. Air contains water vapor (gaseous water). The cold soda can has a low temperature, causing surrounding water vapor to lose heat and chan…
-
visual check 1. identify how many products result from a synthesis reac…
1
-
what do you think? read the two statements below and decide whether you…
Statement 3: D Statement 4: A
-
9. match the elements in the list below with one of the following two d…
(a) \(P\): (ii) dull, brittle insulator (b) \(W\): (i) shiny, ductile, conductor of electricity (c) \(Cu\): (i) shiny, ductile, conductor of electricity (d) \(F\): (ii) dull, brit…
-
balance the chemical equation below, then use the objects in the answer…
\(2S+3O_2 ightarrow2SO_3\)
-
type coefficients in each blank to balance the chemical equation below:…
Coefficients: \(1N_2+3H_2 ightarrow2NH_3\) Reactants: | Atom | Amount | | ---- | ---- | | \(N\) | \(2\) | | \(H\) | \(6\) | Products: | Atom | Amount | | ---- | ---- | | \(N\) | \…
-
instructions instructions for student: reread lines 10-15. then answer …
B. the regular rhyme scheme ### Question 2
-
type coefficients in each blank to balance the chemical equation below:…
The balanced equation is \(2P_4+6O_2 ightarrow4P_2O_3\). For the products: - The number of \(P\) atoms is \(8\) (since \(4\times2\) in \(P_2O_3\)) - The number of \(O\) atoms is \…
-
question 75 to maximize nutrient intake, what is the most important hea…
A. Variety
-
question 69 which of the following is true about organic produce? ○ it …
It is more expensive than conventional produce.
-
identify the number of atoms found in each chemical below: al₂(co₃)₃ 4 …
- \(Al_2(CO_3)_3\): \(2\) aluminum atom(s), \(3\) carbon atom(s), \(9\) oxygen atom(s) - \(4Mg_3(PO_4)_2\): \(12\) magnesium atom(s), \(8\) phosphorus atom(s), \(32\) oxygen atom(…
-
how many σ and π bonds are in this molecule? number of σ bonds: number …
number of σ bonds: 18, number of π bonds: 3
-
which literary techniques does steinbeck use to develop the characters …
A. Symbolism, C. Foreshadowing
-
video worksheet-bill nye \states of matter\ the questions follow along …
s (for each question): 1. matter (and energy, but matter is key here) 2. energy (heat) 3. states 4. energy (heat) 5. pump 6. -196 7. slow 8. slower 9. TRUE 10. FALSE 11. carbon di…
-
17. what is the bond angle of carbon tetrachloride? (0.5 points) * 109.…
17. 109.5 18. 107.8
-
identify the number of atoms found in each chemical below: 2 h₂so₄ 4 pb…
- For \(2H_2SO_4\): \(4\) hydrogen atoms, \(2\) sulfur atoms, \(8\) oxygen atoms. - For \(4Pb(NO_3)_2\): \(4\) lead atoms, \(8\) nitrogen atoms, \(24\) oxygen atoms.
-
15. what shape is the following: (0.5 points) * ash₂br ○ linear ○ bent …
C. Trigonal Pyramidal Iodine heptafluoride
-
13. what shape is the following: (0.5 points) * co₂ ○ linear ○ bent ○ t…
13. Linear 14. Dinitrogen pentoxide
-
11. what shape is the following: (0.5 points) * $ch_4$ ○ linear ○ bent …
11. Tetrahedral 12. Bent
-
9. what shape is the following: (0.5 points) * $c_2h_2$ linear bent tri…
9. Linear 10. Bent
-
7. what shape is the following: (0.5 points) * so₂ ○ linear ○ bent ○ tr…
Bent 104.5
-
5. what shape is the following: (0.5 points) * h₂co ○ linear ○ bent ○ t…
5. Trigonal Planar 6. Trigonal Pyramidal
-
3. what is the bond angle of boron trichloride (0.5 points) * 109.5 107…
120 P₂O₃
-
1. what shape is the following: (0.5 points) * $nh_3$ ○ linear ○ bent ○…
1. C. Trigonal Pyramidal 2. PBr₅
-
1. what is the difference between subscripts and coefficients in a chem…
1. Subscripts show the number of atoms of an element in a molecule, while coefficients show the number of entire molecules or formula units. 2. Below and to the right of the eleme…
-
identify the number of atoms found in each chemical below: li₂co₃ ? lit…
- For \(Li_2CO_3\): \(2\) lithium atoms, \(1\) carbon atom, \(3\) oxygen atoms. - For \(Al_2(NO_3)_3\): \(2\) aluminum atoms, \(3\) nitrogen atoms, \(9\) oxygen atoms.
-
3. potassium is an alkali metal that is one of the electrolytes needed …
For Problem 5 (Calcium): $\boldsymbol{40.08}$ AMU (approximate). For Problem 6 (Tungsten): $\boldsymbol{183.85}$ AMU (approximate). (Note: Calculate similarly for Zirconium using …
-
4. what is an atom? * a type of subatomic particle with no charge a clo…
4. The building block of all matter 5. True
-
question 4 how many significant figures are in the following number? 0.…
3
-
12. where is the energy level the weakest for electrons? * ○ in the nuc…
Q12: the outer shell Q10: atomic mass - atomic number Q2: 2
-
how many significant figures in the following number? 1.0060 4 5 2 1
5
-
7. the place where electrons are most likely to be found is called ____…
Q7: Electron Cloud Q8: isotopes Q6: False
-
9. atoms of the same element with a different number of electrons than …
ions
-
11. the atomic number indicates the number of ______. (choose 2) proton…
protons, electrons
-
abel the ph scale below using the terms from the provided word bank. wo…
1. pH scale: Middle mark: \(7\) (neutral); Far - right mark: \(14\) (base/alkaline) 2. - a. neutral - b. acidic - c. basic/alkaline - d. basic/alkaline - e. basic/alkaline
-
____nacl → ____nano₃ + ____agcl type of reaction: ______________ 13) __…
13) Balanced equation: $2\text{Mg} + \text{O}_2 ightarrow 2\text{MgO}$; Type of reaction: Synthesis 14) Balanced equation: $2\text{Ag} + \text{S} ightarrow \text{Ag}_2\text{S}$; T…
-
question in aqueous solution the $\\ce{co^{2+}}$ ion forms a complex wi…
The balanced chemical equation for the last step in the formation of $\ce{[Co(NH_{3})_{6}]^{2+}}$ from the hydrated ion (considering step - wise, the sixth step) is $\boldsymbol{\…
-
20. choose the best answer. which type of reaction is this? cdso₄(aq) +…
precipitation (the option corresponding to "precipitation" in the multiple - choice, e.g., if the third option is "precipitation", then the answer is the third option with label, …
-
9) ____c₄h₈ + ____o₂ → ____co₂ + ____h₂o type of reaction: combustion 1…
9) Coefficients: 1, 6, 4, 4; Reaction type: Combustion 10) Coefficients: 1, 1, 1, 1; Reaction type: Double Replacement (Neutralization)
-
17. choose the best answer. _____ reactions involve the formation of an…
A. Precipitation ### Question 18
-
14 choose the best answer. when a(n) _____ agent reduces, it causes oxi…
D. reducing (assuming the options are labeled as A. conserving, B. equating, C. oxidizing, D. reducing) ### Question 15
-
11. choose the best answer. ____ is the process in which an atom or ion…
D. Oxidation ### Question 12
-
8. choose the best answer. what is likely a reactant in a combustion re…
B. \( \text{C}_2\text{H}_{10} \) (assuming the options are labeled as A: heat, B: \( \text{C}_2\text{H}_{10} \), C: \( \text{Ca}^+ \), D: light) ### Question 9
-
5. match the correct term to complete the sentence. increasing ______ i…
surface area ### Question 6:
-
practice calculate the average atomic mass for each set of isotopes. 1.…
s: 1. The average atomic mass of carbon is $\boldsymbol{12.0107}$ amu. 2. The average atomic mass of hydrogen is $\boldsymbol{1.0001}$ amu.
-
1 match the correct term to complete the sentence. a(n) reaction absorb…
A(n) endothermic reaction absorbs heat from the surroundings during a chemical reaction. ### Question 2:
-
average atomic mass the bottom number in an element’s box in the period…
The calculated average atomic mass of oxygen, by summing the products of each isotope’s atomic mass and natural abundance, is approximately 15.9994 AMU (matching the periodic tabl…
-
average atomic mass the bottom number in an element’s box in the period…
1. Average atomic mass of carbon: \(\boldsymbol{12.0107}\) AMU 2. Average atomic mass of hydrogen: \(\boldsymbol{1.0001}\) AMU
-
question 3 of 22 figure a and figure b represent examples of different …
- Figure A: non - polar covalent, equal sharing of electrons, \(Cl - Cl\) bond - Figure B: polar covalent, unequal sharing of electrons, \(N - H\) bond
-
analyse : 1- utilisez les substances suivantes pour bâtir une équation …
$\text{CaCO}_3(s) + 2\text{HCl}(aq) ightarrow \text{CaCl}_2(aq) + \text{CO}_2(g) + \text{H}_2\text{O}(l)$
-
3. pour chacune des réactions suivantes, indiquez sil sagit doxydation …
a) Oxydation b) Combustion c) Oxydation d) Oxydation e) Combustion
-
part d: practice problems – balance each equation using the process fro…
Cl₂ + 2NaBr → 2NaCl + Br₂ 3H₂ + N₂ → 2NH₃ 2Na + Br₂ → 2NaBr CuCl₂ + H₂S → CuS + 2HCl 2HgO + Cl₂ → 2HgCl + O₂ C + 2H₂ → CH₄ 2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O
-
part c: balance each of the following equati show your work. p + o₂ → p…
$4\text{P} + 5\text{O}_2 ightarrow \text{P}_4\text{O}_{10}$ $2\text{HgO} ightarrow 2\text{Hg} + \text{O}_2$
-
4. comme l’indique l’équation suivante, décomposer une mole d’eau (h₂o)…
a) Environ 31.8 kJ b) Environ 289 kJ
-
what information is needed to determine the orientation of an orbital? …
- For the orientation of an orbital: \(m_l\) - For the general shape of an orbital: \(l\)
-
l’explication d’avogadro pour avogadro, ce résultat met en évidence l’e…
Le gaz inconnu est le dichlore (\( \text{Cl}_2 \)) car sa masse molaire calculée (≈70.90 g/mol) correspond à celle du \( \text{Cl}_2 \).
-
3. indiquez si les réactions suivantes sont endothermiques ou exothermi…
a) Endothermique b) Exothermique c) Endothermique d) Endothermique
-
2. au cours dune expérience de laboratoire, on neutralise 0,1 mol dacid…
3.3 kJ
-
what values are needed to determine the energy of an electron in a many…
\(\boldsymbol{l}\), \(\boldsymbol{n}\)
-
general chemistry 4th edition mcquarrie·rock·gallogly university scienc…
\(1.7\times10^{-21}\)
-
c’est qu’il s’est produit une réaction de c) une réaction dans laquelle…
a) $\text{MgCl}_2(s) + 3\text{O}_2(g) ightarrow \text{Mg(ClO}_3\text{)}_2(s)$ (Synthèse) b) $4\text{Na}(s) + \text{O}_2(g) ightarrow 2\text{Na}_2\text{O}(s)$ (Synthèse) c) $2\text…
-
13.6 la neutralisation acidobasique manuel, p. 102 et 103 1. parmi les …
b) $\text{Fe(OH)}_{2\text{(aq)}} + \text{H}_2\text{SO}_{4\text{(aq)}} ightarrow \text{FeSO}_{4\text{(aq)}} + 2\text{H}_2\text{O}_{(l)}$ e) $\text{H}_2\text{Se}_{\text{(aq)}} + \te…
-
3. énoncez la loi de la conservation de la masse appliquée aux atomes.
Au cours d'une réaction chimique, les atomes ne sont ni créés ni détruits ; leur nombre par élément reste constant.
-
why is water considered to be a \universal solvent\? it can dissolve ma…
A. It can dissolve many things
-
7. when are crystals formed? ○ when molecules or atoms are arranged in …
when molecules or atoms are arranged in a regular repeating pattern
-
what element is this? sulfur (s) chlorine (cl) silicon (si) phosphorus …
Sulfur (S)
-
liquid a is known to have a higher surface tension and higher viscosity…
- For the first experiment: It's impossible to predict whether \(P_A\) or \(P_B\) will be greater without more information. - For the second experiment: \(F_A\) will be greater th…
-
liquid a is known to have a lower vapor pressure and lower surface tens…
- For the first experiment: Eventually both liquids boil, B first and then A. - For the second experiment: \(F_A\) will be less than \(F_B\)
-
a chemistry student must write down in his lab notebook the concentrati…
$0.1233\ g\cdot mL^{-1}$
-
missed this? watch kcv: reaction stoichiometry, read section 8.3. you c…
$2.010 \times 10^{-3}$ mol
-
in a certain chemical reaction compound a combines with compound b to p…
Theoretical yield of C: \( \boldsymbol{10.8} \) g Actual amount of C: \( \boldsymbol{5.5} \) g
-
when people have difficulty performing the instrumental activities of d…
B. physical disability
-
12. compare the motion of molecules of a hot tea to the molecules of a …
Molecules in hot tea move faster on average than molecules in cold tea.
-
4.) how many electrons can be held in the n=1 or s orbital? (1 point) f…
4. Two 5. 2d
-
1.) what are the shapes of the s and p orbitals? (1 point) s orbitals a…
1. s orbitals are spherical and p orbitals are shaped like dumbbells. 2. 6 3. s<p<d<f
-
3. what determines which element an atom is?
The number of protons (atomic number) in the atom's nucleus determines which element an atom is.
-
4.) electrons in the outermost energy level are called ________ electro…
4. valence 5. 16 orbitals
-
1.) which energy level around the nucleus of an atom has the lowest ene…
1. I 2. Valence electrons determine many of the properties of an atom; Atoms readily lose or gain valence electrons in order to achieve a full outer energy level 3. orbitals
-
which of the following was frank lloyd wright known for? a. creating li…
B. creating "organic" architecture that was part of the surrounding landscape