Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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3 ste nomme les composés suivants. a) sibr4: b) v2o5: c) agcl: d) pbl2:…
# Explications étape par étape: ## Étape 1: Nommer les composés de la question 3 ### a) SiBr₄ Le silicium est un élément et le brome est un autre élément. On a 4 atomes de brome p…
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what is the activation energy? the energy needed to start doing your wo…
The energy needed to start a reaction
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prepwork part 1: for each of the atoms/ions below, write the full elect…
1. Neutral atom of cobalt: 1s²2s²2p⁶3s²3p⁶4s²3d⁷ 2. Chlorine ion with a charge of - 1: 1s²2s²2p⁶3s²3p⁶ 3. Neutral atom of iodine: [Kr]5s²4d¹⁰5p⁵ 4. Neutral atom of vanadium: [Ar]4…
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4. how does lightning fixation occur? a. lightning causes nitrogen gas …
4. a. Lightning causes nitrogen gas molecules to break apart and react with oxygen. 5. b. the conversion of nitrate into atmospheric nitrogen 6. b. combustion of fossil fuels and …
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the chemical formula for an emerald is be₃al₂(sio₃)₆. an emerald can be…
a pure substance because it is a compound.
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a gravel can be broken down into different kinds of substances by physi…
D. heterogeneous mixture
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which is a substance that is made up of only one type of atom? compound…
B. element
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a solid precipitate is formed from the reaction of lead nitrate and sod…
C. filtration
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which best describes an element? a pure substance a type of a mixture a…
a pure substance
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which best describes a compound such as sodium chloride? a pure substan…
a pure substance that can be separated into different elements by chemical means
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which is a characteristic of mixtures? they are chemically bonded toget…
They can be separated by physical processes.
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a teacher makes the following statement. \gasoline boils at a relativel…
distillation of a mixture
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the table shows the percentages of hydrocarbons that are found in a sam…
a mixture
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which cannot be chemically broken down into simpler substances? compoun…
B. element
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9 what is the step 3 of how to calculate average atomic mass? (1 point)…
Add up all the masses. Round to two decimal places and label your answer as "amu".
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there are four isotopes of sulfur: 1) sulfur-32 95.0% abundance 2) sulf…
$32.09$ amu
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7 a unit of mass used to show atomic mass, equal to one - twelfth of th…
atomic mass unit (amu)
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christian conducts an experiment to test the hypothesis that adding sug…
make sure the results are reliable
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6 what is the step 2 of how to calculate average atomic mass? (1 point)…
Multiply each decimal by its mass number.
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part iii: calculate the average atomic mass for the following isotopes.…
1) The average atomic mass of neon is $20.18$. 2) The average atomic mass of element X is $56.8$.
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what is step 1 of how to calculate average atomic mass? (1 point) multi…
Move the decimal two places to the left in each percent abundance.
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all copper in the world exists as two isotopes: 1) copper - 63, which h…
63.62 amu
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two recent models of the atom are shown below. the modem model has repl…
Evidence from new investigations led to the development of the modern model.
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part ii: fill in the chart with the missing information about the given…
| Name Notation | Notation | Mass Number | Atomic # | Protons | Neutrons | Electrons | |---|---|---|---|---|---|---| | Boron - 14 | $_{5}^{14}B$ | 14 | 5 | 5 | 9 | 5 | | Cesium - …
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1. the weighted average of the atomic masses of the naturally occurring…
C. average atomic mass
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solve the question below. (1 point) naturally occurring europium (eu) c…
Eu - 151: 51.5%, Eu - 153: 48.5%
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1. the ______________ depends on the mass number and the percent abunda…
C. average atomic mass
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investigation procedures investigation statement 1 to make a mixture, s…
C. 3
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jacob conducted an investigation to determine the effect of acid on dif…
It might lead to the development of new investigations.
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7. how many grams of lithium sulfate are needed to make 250.0 ml of a 2…
$64.6\ g$
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6. how much of a 0.33 m h2so4 solution is needed to make 500.0 ml 0.075…
$113.6\ mL$
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5. what is the molarity of 18 g of hcl dissolved in enough water to mak…
$0.659\ M$
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the poem \mending wall\ differs from many of frosts poems because... it…
it does not have a consistent rhyme scheme.
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7. balance the following chemical reactions. a) 2c + o₂→ co b) cl₂ + na…
a) $2C + O_2 ightarrow 2CO$ b) $Cl_2 + 2NaBr ightarrow Br_2+2NaCl$ c) $2NH_3 ightarrow N_2 + 3H_2$ d) $2Na + 2H_2O ightarrow 2NaOH + H_2$ e) $2NaOH + H_2S ightarrow Na_2S + 2H_2O$
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5. write a chemical equation from each of the following word equations.…
a) $2H_2O ightarrow 2H_2 + O_2$ b) $2Li + 2H_2O ightarrow 2LiOH + H_2$ c) $Zn + 2HCl ightarrow ZnCl_2+H_2$ d) $KI+AgNO_3 ightarrow KNO_3 + AgI$
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extension: get the gizmo ready: select lithium (li) from the select a m…
1 - A. 1 1 - B. Sodium (Na) 1 - C. 1 2 - Beryllium: 2, Magnesium: 2, Nitrogen: 5, Phosphorus: 5, Oxygen: 6, Sulfur: 6, Fluorine: 7, Chlorine: 7 3. Elements in the same chemical fa…
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the maillard reaction is a chemical process that occurs when foods like…
The Maillard reaction is a chemical reaction that occurs between acids and sugars, causing foods to brown and gain a rich flavor. This process enhances the smell and taste of cert…
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question 4 of 5 which of the following is the correct definition of vit…
D. Nutrients that help the body use proteins, carbohydrates, and fats.
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activity b: ionic compounds get the gizmo ready: click reset. turn off …
1. A. 1 B. 2 C. Yes, because two lithium atoms can each give 1 electron to an oxygen atom, making the lithium atoms stable with 2 electrons in their outer - shell and the oxygen a…
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multiple choice 1 point what was antoine lavoisiers contribution to the…
1. He came up with a widely - read, precise description. 2. Oxygen interacts with iron to form rust.
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activity a: ions get the gizmo ready: • click reset. • check that sodiu…
1. A. Sodium: 11, Chlorine: 17 B. Sodium: 11, Chlorine: 17 2. Sodium: 1, Chlorine: 7 3. A. Sodium: \(+1\), Chlorine: \(-1\) B. Both ions are stable. Sodium ion has a full outer - …
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what was antoine lavoisiers contribution to the law of conservation of …
1. He was the first person to propose it in a scientific way. 2. Oxygen interacts with iron to form rust.
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4 grams of hydrogen and 32 grams of oxygen will combine to form: 36 gra…
A. 36 grams of water B. 6 grams
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student exploration: ionic bonds vocabulary: chemical family, ion, ioni…
1. Nate can give 1 marker to Clara so that each has a full set. 2. Maggie can give 1 marker to Fred and 1 marker to Florence so that each has 8 markers. 3. Sodium: 1; Chlorine: 7 …
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turned dark pink? an indicator was added to the solution which resulted…
- The property that changes when the color change occurs is pH. - Possible sources of error: Inaccurate measurements, impurities in the sample, indicator error.
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29) what is the value of x when the empirical formula is c₅hₓ and the m…
29) E. none of the above 30) A. KO
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22) how many molecules of nitrogen monoxide are in a 22.6 gram sample? …
E. none of the above
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explain how and why the naoh molarity for part a would or would not be …
1. The molarity of NaOH would not be affected because the moles of KHP, which determine the reaction with NaOH, do not change with the volume of water used to dissolve KHP. 2. The…
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15) how many moles of pb are in 4.71 x 10^21 pb atoms? a) 0.00782 b) 6.…
15) A. 0.00782 16) A. 32.0 17) A. Pb 18) A. 0.761 19) B. $2.09\times 10^{25}$ 20) C. 165 21) A. 44.01
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karin compared four different elements. | boron | oxygen | beryllium | …
Oxygen
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true/false. write t if the statement is true and f if the statement is …
1) F 2) T 3) T 4) T 5) T 6) F 7) T 8) F 9) T 10) F 11) F 12) T 13) D. One mole of water contains 1/2 mole of oxygen atoms 14) D. $1.81\times 10^{24}$
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element symbol # of valence electrons valence sum fluorine f 7 1 30 hyd…
6. For non - metals (excluding hydrogen), valence = 8 - number of valence electrons. 7. Hydrogen has 1 valence electron and the first shell can hold 2. It wants to gain 1 electron…
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19. cations have positive charges. anions have negative charges. what f…
19. D. Electrostatic attraction 20. D. There's no way to tell based on the information given
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1) please provide systematic names for the following compounds: a. b. c…
a. 2,5 - dimethylhexane b. (1 - isopropylcyclohexyl)benzene c. (3E) - 3,4 - diethyl - 3 - hexene d. 1,1 - dibromocyclopentene e. 1 - bromo - 2 - methylbenzene
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the relationship between the number of electrons in an atoms outer shel…
1. It refers to sets of eight. 2. Electrostatic attraction
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16 multiple choice 1 point an atom has 15 total electrons. how many val…
16. C. Five 17. B. Ionic
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an atom with 10 electrons must have how many shells? 1 2 8 10
2
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11 multiple choice 1 point in a neutral atom, which of the following mu…
11. Its number of protons is equal to its number of electrons. 12. It relates to protons and neutrons.
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what is the product of the equation shown? 2na + s₂o₃ →? nas₂o₃ nas₄o₃ …
D. $Na_2S_2O_3$
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activity b (continued from previous page) 5. count: review the lewis di…
| Element | Symbol | # of valence electrons | Valence | Sum | | ---- | ---- | ---- | ---- | ---- | | Fluorine | F | 7 | 1 | 30 | | Hydrogen | H | 1 | 1 | | | Oxygen | O | 6 | 2 | …
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whats the easiest way to balance a chemical equation? trial and error u…
1. A. Trial and error 2. C. Three hydrogen atoms
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how do the products of chemical reactions compare to their reactants? t…
1. The products often have completely different properties than the reactants. 2. There is missing oxygen in the product. 3. Balancing.
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sulfuric acid is made of two hydrogen atoms (h), one sulfur atom (s), a…
1. C. $H_2SO_4$ 2. B. Balancing chemical equation 3. C. Lead
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1 multiple choice 1 point which of the following is a chemical reaction…
1. Sodium and chlorine atoms bond to form salt molecules 2. Hydrogen and oxygen molecules
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in general, the first ionization energy increases as you move from left…
Moving from left to right across period 3, electrons populate the same shell (3s and 3p subshells), and the increase in atomic number signifies that the force of attraction will i…
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3. draw a diagram: draw a lewis diagram of the oxygen molecule in the s…
Oxygen molecule: $:O::O:$ Nitrogen: $:N:::N:$ Ammonia: $H - \underset{\overset{\mid}{H}}{N}-H$ (with lone pair on N) Chlorine: $:Cl - Cl:$ Methane: $H - \underset{\overset{\mid}{H…
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activity b: building molecules get the gizmo ready: • click reset. • tu…
A. 6 B. 2 2 (for the number of pairs of shared electrons in a stable molecule of oxygen)
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activity b: building molecules get the gizmo ready: click reset. turn o…
A. 6 B. 2 2. 2
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1. how many grams of o2 are needed to produce 157.4 g of co2 from the c…
114.5 g (rounded to one decimal place)
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activity a: sharing electrons get the gizmo ready: • click reset. • sel…
1. Two hydrogen atoms can share their single electrons to achieve a stable configuration with 2 electrons each. 2. The Lewis diagram for $H_2$ is $H - H$. 4. The Lewis diagram for…
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what is the minimum grams of protein that a non - athletic male who wei…
Question 1: C. 76 grams Question 2: They consume all food groups with plenty of calories in their diet
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an empty beaker has a mass of 60.0 grams. when mercury is added to the …
140.0 g
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is the phrase in bold a direct object, an indirect object, or neither? …
# Breve explicación: El objeto directo es el que recibe directamente la acción del verbo. En la frase "My cousin always buys organic produce from the grocery store", la acción de …
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your organizations disaster or emergency preparedness plan addresses ev…
1. A. True 2. D. Watch 3. A. True 4. A. True 5. B. False 6. A. Medical
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14. explain the difference between: a. an atom and an element. b. a mol…
14a. An atom is the smallest unit of an element; an element is a pure - substance of one atom type. 14b. A molecule is a group of atoms; a compound is made of different elements i…
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a specific oxygen atom has 8 protons and 10 neutrons. if this is a neut…
D. 8
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3. argon (ar) has two stable isotopes: ³⁶ar, ³⁸ar, and ⁴⁰ar. based on t…
a) The % abundance of \(^{40}\text{Ar}\) is expected to be much greater than 50% because the average atomic mass of Ar (39.95) is very close to the mass of \(^{40}\text{Ar}\) (39.…
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an atoms nucleus contains 8 particles that have no charge and 6 particl…
D. 6
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part 3: continued... 1. how does the number of electrons change as you …
1. The number of electrons increases by 1 as you move from left to right across a period. 2. All atoms of Group 1A elements have 1 valence electron. 3. Three things that all atoms…
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which strategies did the united states employ in order to achieve victo…
B. island - hopping D. bombing
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when you observe a chemical property, like flammability or reactivity, …
No, the substance remains the same. For example, burning wood stays as wood (partially un - burned).
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part iii. fill in the isotope names and any missing information on the …
| Element | Isotope Name | # of Protons | # of Neutrons | # of Electrons | |---|---|---|---|---| | Manganese | Manganese - 42 | 25 | 17 | 25 | | Phosphorus | Phosphorus - 30 | 15 …
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warm up molecular geometry 1. count the total valence e - of the compou…
For \(BI_3\): Molecular geometry is trigonal planar, and it is polar. For \(C_2H_2\): Molecular geometry is linear, and it is non - polar.
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a student finds an object with a mass of 64.54 g and a volume of 14 cm³…
The object is not gold because its calculated density (approximately 4.61 g/cm³) is different from the density of gold (19.32 g/cm³).
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part iii. fill in the isotope names and any missing information on the …
| | Iron - 53 | Iron - 56 | Chromium - 54 | Chromium - 56 | |--|--|--|--|--| | # of protons | 26 | 26 | 24 | 24 | | # of neutrons | 27 | 30 | 30 | 32 | | # of electrons | 26 | 26 …
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c. for the following electron configurations determine the possible ele…
17. Selenium (Se) 18. Krypton (Kr) 19. Ytterbium (Yb) 20. Manganese (Mn) 21. Antimony (Sb) 22. Potassium (K) 23. Dysprosium (Dy) 24. Aluminium (Al)
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part iii. fill in the isotope names and any missing information on the …
| Element | # of protons | # of neutrons | # of electrons | | ---- | ---- | ---- | ---- | | Palladium | 46 | 48 | 46 | | Palladium | 46 | 51 | 46 | | Cesium | 55 | 113 | 55 | | Ce…
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part iii. fill in the isotope names and any missing information on the …
| | First Column | Second Column | |--|--|--| | First incomplete table (top - right) | Protons: 32, Electrons: 32 | Protons: 32, Electrons: 32 | | Second incomplete table (middle …
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electron configuration practice chemistry 8. write a ground - state ele…
11. $1s^{2}2s^{2}2p^{6}$ 12. $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{6}$ 13. $1s^{2}$ 14. $1s^{2}2s^{2}2p^{5}$ 15. $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}$ 16. $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}$
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part a what is an element? a compound? compound cannot be broken down i…
The second option: Element cannot be broken down into two or more simpler substances. Compound is made up of two or more elements in a fixed ratio and can be broken down into simp…
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part iii. fill in the isotope names and any missing information on the …
| Isotope Name | # of Protons | # of Neutrons | # of Electrons | |--|--|--|--| | Manganese - 42 | 25 | 17 | 25 | | Phosphorus - 30 | 15 | 15 | 15 | | Germanium - 62 | 32 | 30 | 32…
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part iii. fill in the isotope names and any missing information on the …
| Isotope Name | # of Protons | # of Neutrons | # of Electrons | | ---- | ---- | ---- | ---- | | Copper - 46 | 29 | 17 | 29 | | Germanium - 62 | 32 | 30 | 32 | | Germanium - 64 | …
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electron configuration practice chemistry how to write an electron conf…
1. $1s^{2}2s^{2}2p^{6}3s^{1}$ 2. $[Xe]4f^{14}5d^{10}6s^{2}6p^{2}$ 3. $[Kr]5s^{2}$ 4. $[Rn]5f^{3}6d^{1}7s^{2}$ 5. $1s^{2}2s^{2}2p^{3}$ 6. $[Kr]4d^{10}5s^{1}$ 7. $1s^{2}2s^{2}2p^{6}…
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atomic mass. in other words, isotopes have the same number of proton an…
| | Carbon - 12 | Carbon - 13 | Carbon - 14 | |--|--|--|--| | # of protons | 6 | 6 | 6 | | # of neutrons | 6 | 7 | 8 | | # of electrons | 6 | 6 | 6 |
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part ii. for each of the following isotopes, write the number of proton…
| Isotope | # of protons | # of neutrons | # of electrons | | ---- | ---- | ---- | ---- | | Carbon - 12 | 6 | 6 | 6 | | Carbon - 13 | 6 | 7 | 6 | | Carbon - 14 | 6 | 8 | 6 | | Chr…
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part i. answer the questions based on the above reading. 1. what is an …
1. Atoms of the same element with the same number of protons but different numbers of neutrons. 2. The mass - number, which is the sum of protons and neutrons in the nucleus. 3. B…
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6. calculate moles of acid assuming the sample is diprotic for two tria…
$0.710846184$
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student exploration: covalent bonds vocabulary: covalent bond, diatomic…
1. Flora and Frank can trade the markers they are missing (Flora gives Frank her blue - marker and Frank gives Flora his red - marker). 2. Otto and Olivia can trade the markers th…
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a chemist has a container of 12% peroxide solution and a container of 2…
$\begin{bmatrix}0.12&0.2\\1&1\end{bmatrix}\begin{bmatrix}x\\y\end{bmatrix}=\begin{bmatrix}14\\100\end{bmatrix}$ (corresponding to the second option in the multiple - choice list)
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reading read the two passages. then, choose the best answer to each que…
A. King Lear will die of grief and his children will all come to bad ends.