AS MOVE COURSE
PART 1: MEASURING AMOUNT OF SUBSTANCE
OCR Chemistry A
Unit one particular вЂ“ Slide Term 2012
вЂў Atoms and Electron Structure
вЂў Moles, Equations and Acids
вЂў Framework and Bonding
вЂў Redox, Group two and Group 7
Device 1 Exam вЂ“ January 2013 вЂ“ 1 hour вЂ“ 90 UMS вЂ“ thirty percent of total
Unit two вЂ“ Springtime Term 2013
вЂў Basic Concepts in Organic Biochemistry
вЂў Alkanes and Alkenes
вЂў Haloalkanes and Alcohols
вЂў Enthalpy Changes
вЂў Rates and Equilibrium
вЂў Modern Synthetic Techniques
вЂў Chemistry from the Air
Unit 2 Test вЂ“ May well 2013 вЂ“ 1 hr 45 a few minutes вЂ“ 150 UMS вЂ“ 50% of total
Unit 3 вЂ“ Autumn Term 2012 and Spring Term 2013
Inside Assessments вЂ“ 60 UMS вЂ“ 20% of total
MEASUREMENTS IN CHEMISTRY
Convert this into grms:
a) zero. 25 kilogram
b) 15 kg
c) 100 tonnes
d) two tonnes
Convert the subsequent into dm3:
a) 100 cm3
b) 25 cm3
c) 50 m3
d) 50000 cm3
Tip вЂ“ always use normal form pertaining to very large and incredibly small amounts!
What is a mole?
Atoms and molecules are very small вЂ“ far too promising small to count individually!
It is important to be aware of how much of something we have, but all of us count contaminants in SKIN MOLES because you get easier numbers
1 mole sama dengan 6. 02 x 1023 particles
(6. 02 back button 1023 is called Avogadro's number)
a) For those who have 2 . five x 1021 atoms of magnesium, how many moles do you have?
b) If you have zero. 25 skin moles of co2, how many molecules do you have?
How can you work out how various moles you could have?
a) From a measurement of MASS:
You can find the quantity of moles of the substance in case you are given it is mass therefore you know the molar mass:
number of moles=mass/molar mass
Mass MUST be scored in grms!
Molar mass has units of gmol-1
|1. Calculate the number of skin moles present |2. Calculate the mass of: |3. Determine the molar mass in the | |in: | |following substances: | |a) 2 . 3 g of Na |a) 0. 05 skin moles of Cl2 |a) zero. 015 skin moles, 0. forty two g | |b) installment payments on your 5 g of UNITED KINGDOM |b) 0. 125 moles of KBr |b) zero. 0125 skin moles, 0. 60 g | |c) 240 kg of CO2 |c) 0. 075 moles of Ca(OH)2 |c) 0. fifty-five moles, 88 g | |d) doze. 5 g of Al(OH)3 |d) two hundred and fifty moles of Fe2O3 |d) 2 . twenty-five moles, 63 g | |e) five. 2 g of PbO2 |e) zero. 02 moles of Al2(SO4)3 |e) 0. 00125 skin moles, 0. 312 g
b) Coming from a way of measuring of AQUEOUS VOLUME:
You will discover the number of skin moles of a element dissolved in water (aqueous) if you are provided the volume of solution therefore you know the molar attention:
number of moles=aqueous volume xmolar concentration
Aqueous volume Should be measured in dm3!
attentiveness has units of moldm-3
If you know the dimensions of the molar mass of the material, you can convert the molar concentration to a mass focus:
Molar attentiveness (moldm-3) xmr=mass concentration (gdm-3)
|1. Compute the number of moles of |2. Calculate the molar attentiveness and |3. Calculate the molar focus and | |substance within each of the following |the mass concentration in the following |the mass attentiveness of the subsequent | |solutions: |solutions: |solutions:...