Summary
Samenvatting Chemisch rekenen
- Course
- Institution
- Book
goede samenvatting voor toets/examen
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
Seller
Follow
joniehinion
Content preview
Chemisch rekenen1. Atoommassa
Aa = absolute atoommassa in gram -> zeer klein dus werken met Ar
Ar = relatieve atoommassa (kan je aflezen in periodiek ss) verteld hoeveel x een atoom zwaarder is dan een H-atoom
of amu
We vergelijken de Aa met de Aa van een H- atoom die komt overeen met de amu (= atoommassa unit)
Amu = 1,66 . 10 -27 kg
Vb. Ar (C) Aa van H vergelijken met de Aa van C = 12, 0 (altijd 1 cijfer na komma!)
2. Moleculemassa
Ma = absolute moleculemassa
Mr = relatieve moleculemassa = de som van alle Ar van de aanwezige atomen
Vb. Mr (H2O) = 2 . Ar (H) + Ar (O) = 2 . 1,0 + 16,0 = 18,0
3. Stofhoeveelheid (n) met eenheid mol
Stofhoeveelheid = hoeveelheid om te kunnen spreken over de hoeveelheid v/e stof
o 1 paar = 2
o 1 dozijn = 12
o 1 mol = 6,02 . 1023 = getal van Avogrado = Na eenheid van de stofhoeveelheid
Bepaalt aantal deeltjes per mol
Er zijn 6,02 . 1023 deeltjes (atomen of moleculen) in 1 mol stof
Na = 6,02 . 1023 mol -1 (mol-1 = 1/mol = per mol)
Hoeveel weegt 1 mol?
Als je 1 mol v/e atoom wil Ar g afwegen vb. 1 mol ijzer = 55,8 g (Ar (fe) = 55,9)
Als je 1 mol v/e molecule wil Mr g afwegen vb. 1 H2O = 18,0 g (Mr (H2O) = Ar(H) . 2 + Ar (O)
Extra vb. 1 mol Na = 23 g (Ar (Na) = 23,0 g)
Zijn er overal evenveel deeltjes?
Ja, 1 mol = 6,02 . 1023
Is de massa overal gelijk?
Nee, dit hangt af v/d moleculen/atomen vb. 50 grote en 50 kleine haribo bollen snoepjes
4. Molaire massa
Molaire massa = de massa in gram van 1 mol deeltjes
De molaire massa v/e stof is de waarde van Ar of Mr uitgedrukt in g/mol
Vb. M(fe) = 55,8 g/mol en M(H2O) = 18,0 g/mol
m m
Dus M = n= m = n . M
n M
Om een aantal deeltjes N (atomen of moleculen) te berekenen in x mol v/e stof gebruik je deze formule:
N
N = n . NA of n =
NA
Vb. wat is de M van 1 mol zwavel?
A: 32:1
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller joniehinion. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $6.96. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
67474 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now