Amount of Substance Flashcards
Equation for number of particles?
No. of particles = No. of moles x avogadro’s constant
1st Equation for moles?
Moles = Mass/Mr
2nd Equation for moles?
No. of moles= concentration x volume
/
1000 (for dm3)
Gas law equation?
Original and re-arranged
pV= nRT -ORIGINAL V= nRT/p p=nRT/V R= pV/nT n= pV/RT t= pV/nR
Gas law equations conversions?
Pressure
Volume
Temperature
KPa - Pa x1000 cm3- m3 /100 dm3 - m3 -1000 cm3 - dm3 - /1000000 (million) c - k +273
What happens to temperature, moles and volume when then increase or decrease?
Temp. increase - Volume decreases
Temp. decrease - Volume increases
Pressure increase - Volume decreases
Pressure decrease - Volume increases
Moles increase - Volume increases
Moles decrease - Volume decreases
Describe reaction between all metals and acids and their products?
Metal Carbonate + Acid - Salt + Water + Carbon Dioxide
Metal + Acid - Salt + Hydrogen
Metal Oxide (base) + Acid - Salt + Water
Alkali (hydroxide) + Acid - Salt + Water
Rule for writing ionic equations?
If you have a substance that is aqueous, it will split up into its ions but not solids, liquids and gases.
Describe spectator ions?
They are ions that haven’t changed in a reaction
Explain the meaning of Empirical Formula?
The simplest whole number ratio of atoms of each element in a compound.
Explain the meaning of Molecular Formula?
They show that actual number of atoms of each element in a compound.
Using combustion values?
- Burn a specific amount of compound that produces H20 AND CO2
- Drying agent will absorb all the H20
- Sodae will absorb all of C02
- Measuring the change in mass and percentage of carbon and hydrogen will enable you to deduct empirical formula.
What is the limiting reagent?
Why do we use them?
The chemical not in excess and stops the reaction.
We use them because it is rare that you react the exact right amount of chemicals.
What is the law of conservation of mass?
mass of reactants = mass of products
How can atoms be lost in a reaction?
- evaporation
- reversible reaction
- reactant lost in transportation
- unwanted side reactions
