Calculations of Unit 1 Flashcards
What is the equation linking Avogadro’s constant to moles?
number of particles/atoms/ions = Moles x Avogadro’s constant ( 6.02 x 10 * 23)
What is an ionic equation?
Ionic equations only show the reacting ions and can be written for any reaction involving an ion in solution. The ions not included are called spectator ions.
e.g. Ag+ (aq) + Cl-(aq) →AgCl (s)
Define molar mass
The mass per mole of a substance measured in g mol-1
Define ppm
parts per million: the ratio of one gas to another
Define concentration
Concentration is the amount of solute dissolved per dm cubed of solution
How can concentration be calculated in g dm -3?
Concentration ( g dm-3) + mass (g) / Volume (dm3)
How can concentration be calculated in mol dm-3?
Concentration =moles/ volume (dm3)
What is RTP?
Room temperature and pressure:
- 20℃
- 1 atmosphere
What equation links molar volume at RTP and moles?
Volume of gas at RTP (dm3) = moles x 24
Why might the actual yield of product be less than expected?
- Incomplete reaction
-Unwated side reactions
-Practical losses; for example, some solids may get lost when being transferred between beakers
How can atom economy be calculated?
ATom economy = ( molar mass of desired product divded by total molar mass of products) x 100
Fill in the gap: “ The ……. the atom economy, the more sustainable and efficient the process”
The higher the atom economy, the more sustainable and efficient the process
What are displacement reactions?
A displacement reactions occurs when one element replaces another element in a compound.
A = BC →b + AC
What is the ideal gas law formula?
PV=nRT
P = Pressure (in Pascals, Pa)
V = Volume (in cubic meters, m³)
n = Number of moles (mol)
R = Ideal gas constant - 8.31
T = Temperature (in Kelvin, K)
How can percentage yield be calculated?
Percentage yield = ( Actual yield divided by theoretical yield) x 100
