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- Indicazione della massa atomica (Atom-04)L'indicazione della massa atomica relativa (sul sistema periodico) è per un singolo atomo o un Mol?
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in: Atombau_it
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- 1 week, 4 days ago
- Stabilste Ionen (Salze-10)Gegeben seien folgende Atome: Aluminium, Fluor, 4Be, Kalium, 52Te, Neon, Calcium, Schwefel und Stickstoff.
Bestimme die Anzahl der Valenzelektronen von jedem Atom und leite damit das häufigste Ion her.Started by:
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- Calculate using the reaction equation 4 (st-74)A reaction produces 54 grams of water.
- … into a liquid state?
- … in the gaseous state under normal conditions?
- … In the gaseous state of operation at a pressure of 3 bar and 70℃ a?
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- Loi de Coulomb, application 5 (Atom-24)Deux particules ayant la même charge positive sont éloignées l'une de l'autre. Comment la force de rejet change-t-elle lorsque la distance est triplée?
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- Determinare il numero di protoni, neutroni ed elettroni (Atom-05)Determina il numero di protoni, neutroni ed elettroni nei nuclei atomici seguenti:
numero… Protoni Neutroni Electroni 31H 52He 13C 234U 13C2+ 34S2- 4He2+ 17O 200Au+ 78Br– Started by:
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- Calculate using the reaction equation 5 (st-75)It's all about making salt.
For the production of 150 g of salt, 70 g of sodium are supplied to react with chlorine to sodium chloride.Started by:
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- 1 week, 4 days ago
- Loi de Coulomb, application 6 (Atom-25)Deux particules ayant la même charge positive sont éloignées l'une de l'autre. Comment la force change-t-elle lorsque l'écart est triplé et que la charge d'une particule est quadruplée?
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- Salzformel bilden (Salze-20)Schreibe alle (binären) Salzformeln auf, welche sich aus den häufigsten Ionen folgender Elemente bilden lassen:
Brom, Sauerstoff, Kalium, Aluminium, Calcium sowie StickstoffStarted by:
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- 1 week, 4 days ago
- Numero di protoni ed elettroni (Atom-06)Si deve dare la seguente notazione: H2, H+2, H2+ Quale notazione è completamente sbagliata?
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- 1 week, 4 days ago
- Calculate using the reaction equation 55 (st-76)Various exercises around the chemical computation.
- easy exercises
- (a) The formula for methyl alcohol is CH3OH. What molecular weight does such a molecule have?
- b) how many oxygen atoms contain 1 g O2-molecules?
- (c) How many atoms does 1g of helium gas contain?
- (d) How many grams correspond to 1 mol of sulphur, 1 mol of sodium and 1 mol of water?
- (e) The mass of:
0.5 mol carbon dioxide (formula CO2)
0.1mol of sulphuric acid (H2SO4)? - (f) What is the molecular weight of a substance when 0.87 mol of it weighs 24.36 g?
- (g) How many C atoms contain 24 g of carbon?
- (h) How many oxygen atoms contain 1 g ozone (O3)? indication in Mol (n) and 'real' number
- intermediate exercises
- (i) How much gram of water is formed by burning 100 g of methane (CH4)?
- (j) Lead (Pb304) can be obtained from lead oxide (PbO) by oxidation with oxygen. Calculate the mass of lead oxide required to produce 100 kg of lead.
- (k) Alcohol (C2H5OH) is normally represented by the dilution of glucose (C6H12O6) according to the reaction equation:
Glucose molecule –> 2 alcohol molecules + 2 carbon dioxide molecules
How much kg alcohol to leave itself from 2 kg glucose winning? - difficult exercises
- (l) How many grams of zinc sulphide (ZnS) do we get when we convert 200 g of zinc into 1000 g of sulphur (S8)?
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- Modèle atomique de Bohr, 1 (Atom-30)Expliquer l'origine de la lumière à l'aide du modèle atomique de Bohr
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- Électrons de valence (Atom-31)Quels sont les électrons de valence ?
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- Bilde Salze aus Ionen, 1 (Salze-21)Welche Salze ('Salzformeln') lassen sich aus den folgenden Ionen bilden:
Al3+ / NH+4 / Fe2+ / Fe3+ / Na+ / Mn2+ / O2- / S2- / NO3– / Br– / SO2-4 / H2PO4– / CO2-3 / PO3-4Started by:
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- Che cosa è un isotopo (Atom-10)Che cosa è un isotopo?
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- Calculate using the reaction equation 6A car consumed on 100 km 10 litres [translation unavailable].
(st-77)
(a) Calculate the mass of the carbon dioxide produced.
(b) Calculate the volume taken up by the resulting carbon dioxide.
Assumption: Diesel consists of a single component: C15H32Started by:
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- 1 week, 4 days ago
- Calculate using the reaction equation 7 (st-78)Calculate the masses of all the particles involved in the following reaction equations
- PbO + C → Pb + CO2, given 0.528 g C.
M(PbO) = 223.2 g/mol, M(Pb) = 207.2 g/mol, M(CO2) = 44 g/mol - NaCl → Na + Cl2, given be 100 g Na.
M(NaCl) = 58.5 g/mol, M(Cl2) = 71 g/mol - Fe + O2 → Fe2O3, give 100 tonnes of iron.
M(O2) = 32 g/mol, M(Fe2O3) = 159.6 g/mol - Sodium (Na) and chlorine gas (Cl2) are produced by melting electrolysis (a special technical procedure) from sodium chloride (NaCl). Write the reaction equation and calculate how much gram of sodium chloride is required to obtain 100.0 g of sodium.
- Calcium carbide (CaC2) is a solid that forms a flammable gas with water.
reaction equation: Ca + 2·C → CaC2
How much kg of CaC2 do you get when you use 50 kg of Ca? How much kg of carbon is needed for this?
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- PbO + C → Pb + CO2, given 0.528 g C.
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- Nommage des électrons (Atom-32)Comment s'appellent les électrons dans la dernière / dernière écaille ?
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- Bilde Salze aus Ionen, 2 (Salze-22)Welche Salze ('Salzformeln') lassen sich aus den folgenden Ionen bilden:
Al3+ / NH+4 / Fe2+ / Fe3+ / Na+ / Mn2+ / O2- / S2- / NO3– / Br– / SO2-4 / H2PO4– / CO2-3 / PO3-4
Hinweis: die Ionen sollen nach ihrer Ladung aufgelistet werden, also zuerst die einfach positiven, dann die zweifach positiven etc. Und: wie auch sonst: mit einer Tabelle wird die Sache übersichtlicher.Started by:
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- Elementi diversi di massa uguale (Atom-11)Inserimento{isotopi:} notare due diverse elementi (inclusi numero di massa), quali le stesso masse hanno.
Accettazione: m(p) = m (n), la massa il elettroni dovrebbe in questa esercizio trascurato sono.Started by:
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- Gas equation 1 (st-80)What is the general (ideal) gas equation and what is it?
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- Modèle atomique de Bohr (Atom-33)Pour tous les éléments suivants, indiquez combien
- Les électrons qu'ils ont au total
- Combien de électrons de valence sont présents
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- Ionen, Salzformel aus Salzname herleiten (Salze-23)Gegeben seien die Namen folgender Salze. Ergänze die Tabelle!
Name des Salzes Kation Lewisformel des Anions Salzformel Natriumsulfat Kaliumnitrat Calciumphosphat Magnesiumcarbonat Ammoniumchlorid Blei(II)-sulfid Eisen(II)-oxid Eisen(III)-oxid Aluminiumcarbid Kaliumpermanganat Natriumacetat Aluminiumoxid Started by:
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- Generale, struttura atomica, isotopo (Atom-12)Che cosa hanno in comune i tre atomi di silicio 28Si, 29Si, 30Si, cosa è diverso?
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- Gas equation 2 (st-81)[translation unavailable] he speaks one in fact, of the 'ideal' gas equation?
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- Dessinez le modèle atomique de Bohr (Atom-34)Dessinez le modèle atomique de Bohr pour les éléments suivants: fluor, magnésium, silicium.
Pour chaque modèle, les informations suivantes doivent également être fournies:
– nombre électrons de valence
– Indication de la coque de valence
– les écailles qui appartiennent au tronc nucléaire
– Chargement de la corbeilleStarted by:
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- Unterschiedliche Salze bilden (Salze-24)Bilde folgende Salze aus den neutralen Elementen und schreibe die ausgeglichene Reaktionsgleichung auf:
- NaCl
- MgO
- KBr
- Al2O3
- Eisen(II)oxid
- Eisen(III)oxid
- Natriumoxid
- Calciumoxid
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- Presumibilmente stesso molecole, ma diversi massa, struttura atomica (Atom-13)La reazione di bromo con idrogeno produce il gas bromo idrogeno (HBr). I seguenti isotopi partecipano alla reazione: 1H, 2H, 79Br e 81Br.
- Qual è l'equazione di reazione equilibrata?
- Quante diverse molecole di HBr di massa diversa si formano?
- Quale combinazione di isotopi sarebbe la HBr più leggera, quale è la molecola di HBr più pesante? Indicazione inclusa massa molare.
Supposizioni per la masse molari: si calcola con la semplificazione che m(Proton) = m(Neutron). si applica quanto segue:
M(1H) = 1 g/mol, M(2H) = 2 g/mol, M(79Br) = 79 g/mol e M(81Br) = 81 g/mol.Started by:
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- Molar volume 1 (st-83)What do you mean by molar volume?
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- Configuration électronique (Atom-35)Comment est les complète configuration électronique suivants éléments.
- C
- Nitrogen
- Cu
- Na+
- O2-
- Ca2+
- Un élément de 31 électrons
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- Aus Salzen Ionen bilden (Salze-25)Gegeben seien folgende Salze. Welches sind die zugehörenden Ionen ? Deren Anzahl muss aber nicht bestimmt werden. Das erste Beispiel ist schon gelöst.
- NaCl: Na+ / Cl–
- Al2O3
- MgO
- KBr
- FeO
- Fe2O3
- Na2O
- CaO
- (NH4)2HPO4
- Ca(H2PO4)2
- Fe(NO3)3
- Ba(ClO3)2
- Ca(OH)2
- Ca3(PO4)2
- Zn(HCO3)2
- LiCO3
- Na2H2P2O7
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- Frequenza percentuale 1, struttura atomica (Atom-14)Qual è la percentuale di 28Si e 29Si, se la percentuale di massa di 30Si è 3.1 %?
Nota: m(28Si) = 27.9769 u, m(29Si) = 28.9765 u, m(30Si) = 29.9738 uStarted by:
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- Various calculations, ideal gas law (st-84)Different calculations
- At a pressure of 75 kPa, a gas sample takes up a volume of 360 ml. What volume does the sample take up at the same temperature under a pressure of 100 kPa ?
- The volumes a gas sample is 462 ml at 35 ℃ and 115 kPa. What 's the volume under normal conditions ?
- The quantity of litres of CO (g) measured under normal conditions is required to produce 1.0 kg of rust (Fe2O3) by the following masses:
Fe2O3 + CO → Fe + CO2 - A Mol of a gas claims at normal conditions 22.4 litres. Calculate the side length of the Mol spindle.
- How many pounds of air are in a classroom?
Assumptions: 180 m3, 20 ℃ 100'000 Pa, air 80% N2, 20% O2
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- Le nombre possible de liaisons d’un atome d’hydrogène (Atom-40)Combien de liaisons un atome d'hydrogène peut-il faire ?
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- Benenne folgende Ionen und Salze (Salze-30)Gegeben seien folgende Ionen sowie Salze. Benenne diese mit ihrem Namen. Beachte, dass bei den Übergangsmetallen die Ladung mit römischen Ziffern angegeben werden muss.
- NaCl:
- F– :
- SO2-4 :
- O2- :
- NaNO3 :
- Al2O3:
- FeO :
- Fe2O3 :
- NaS :
- C4- :
- CaO2:
- NaHCO3–:
- Na2SO4:
- NH4+:
- PbS:
- Al4C3:
- (NH4)(NO3):
- AlBr3 :
- Fe(NO3)3 :
- (NH4)2S :
- Fe3(PO4)2 :
- Fe(HPO4) :
- Fe(H2PO4)3 :
- Fe2(SO4)3 :
- Fe(HSO4)2 :
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- Frequenza percentuale 2, struttura atomica (Atom-15)Più naturale carbonio esiste a 98.94% da 12C, il restante esistono da 13C (m=13.003355 u).
- Sulla base di questi valori calcoli la massa media di carbonio attesa.
- Cosa si può dedurre dal valore effettivo di 12.0107 (valore PSE)?
- Calcola le a attesa media massa di carbonio con il idea, che le masse di m(12C)=12u e m(13C)=13u quantità.
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- Concentration, exercise 1233 (st-90)Different calculations around the concentration.
- 5 grams of salt is added to a liter of water. What concentration does the solution have?
- 18 g C6H12O6 is dissolved in 120 ml of water. What concentration does the solution have?
- 10 ml of a 0.02 mol/l vitamin C solution were produced.
Notes: M(Vitamin C) = 176.13 g/mol - 100 ml of magnesium bromide solution (MgBr2) with a concentration of c = 0.02 mol/L is to be produced.
How can this solution be made in a chemical laboratory? - One liter of a salt solution weighs 1.34 kg. What concentration does the solution have?
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- Des molécules dessinent 1notation de Lewis: Comment les éléments sont-ils représentés dans l'orthographe de Lewis? (Atom-43)
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- Typische Salze (Salze-31)Nenne zehn typische Salze.
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- Frequenza percentuale 3, struttura atomica (Atom-16)L'elemento cloro è composto da due isotopi: 35Cl e 37Cl. m(35Cl) = 34.969 u, frequenza = 75.77%, m(37Cl) = 36.966 u.
Calcolare la massa media di un cloratomo e interpretare il risultato.Started by:
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- Concentration, exercise 12 (st-92)1 grams [translation unavailable] should on the oceans and seas distributed are. How many gold atoms are there per liter?
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- Dessin des molécules 2Liaison simple: dessinez les molécules H2O, CH4, H2O2, NH3, C2H6O (deux différentes les variantes) (Atom-44)
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- Magnesiumtetroxid (Salze-32)Jemand behauptet, dass MgO4 ein Wundermittel gegen Dummheit wäre. Lohnt sich ein Kauf?
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- Frequenza percentuale 4, struttura atomica (Atom-17)Il bromo si presenta in natura come miscela dei due isotopi stabili 79Br e 81Br. Frequenze: 79Br a 50.65%, m = 78.918338 u. Calcolare dalla media massa molare del freno ora la frequenza e la massa del 81Br in u e g/mol.
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- Mehratomige Anionen zeichnen (Salze-40)Zeichne folgende mehratomigen Anionen:
- Sulfat
- Nitrat
- Carbonat
- Hydrogensulfat
- Phosphat
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- Frequenza percentuale 5, struttura atomica (Atom-18)Un elemento è costituito da una miscela di tre isotopi, i cui due isotopi più leggeri hanno le stesse frequenze. L'masse molari dei tre isotopi è anche noto.
Calcola di cui: le generale formula il medie massa molare del elementi.Started by:
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- Concentration, exercise 10 (st-93)Calculate the concentration of household sugar (C12H22O11), in a cup coffee (150 ml), where: [translation unavailable] a cabbage sugar (m = 7.7 g) dissolved is.
Addition: How many molecules of caffeine (C8H10N4O2) are present in the body after a cup of coffee, when in a Cup coffee 80 mg of which: dissolved were?Started by:
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- Molécules dessiner, règle de l’octetRègle de l’octet (y compris à caractère obligatoire – pas à caractère obligatoire couples d'électrons): comment peut la raison une dessinées la structure tout simplement et rapidement décidés sont, ou le molécule en principe correctement est? (Atom-45)
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- Lösung mit gegebener Konzentration herstellen (Salze-50)Stelle 0.4 Liter eine 0.2 mol/l NaCl-Lösung her im Labor mit einer Waage und Messkolben her.
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- Isotopi: frequenza percentuale 6, struttura atomica (Atom-19)L'argento si trova come miscela di due isotopi, 107Ag, massa atomica 106.906 u e 109Ag con massa atomica 108.905 u. Qual è la percentuale di partecipazione di ogni isotopo? Calcolo solo fino a a al punto, fino a le equazione solo ancora una sconosciuti maggiore ha.
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