everything u need to know for exam Flashcards
What’s the amphoteric character of alumina?
It can react with acids and bases to form different products.
What’s formed when alumina reacts with an acid?
Salt and water
What’s formed when alumina reacts with a base?
A soluble aluminate salt.
Why is calcium hydroxide (ca(oh)2) widely used in treating acid effluent?
it is a strong base which helps neutralise acidic waste.
How does calcium hydroxide help to reduce acid effluent?
when it neutralises acidic waste, less harmful products such as water and salts are formed.
What are two benefits of using calcium hydroxide to treat acid effluent?
It’s cost-effective and is effective in neutralising strong acids.
what are some limitations of using calcium hydroxide to treat acid effluent.
Over-usage could lead to PH rising, may cause sludge formation.
in the Haber process, what is the difference in the enthalpy profile between an uncatalysed and catalyst reaction?
in the uncatalysed reaction, the activation energy is higher, in a catalyst reaction the activation energy is lower
explain the effects of using a catalyst in the Haber process. (4)
-The reaction is sped up.
-The bonds of the particles in the reactants are weakened.
-A surface is formed for the particles to react upon.
-This provides a more efficient & cheaper reaction.
name the four properties of ionic substances.
they have a giant ionic lattice,
they have many strong electrostatic attractions between oppositely charged ions
Don’t conduct if solid, but will if dissolved or in molten form
complete the definition for standard entropy change of hydration.
The enthalpy change when ___ mole of ions in the _______ state or dissolved in water to infinite dilution standard conditions (____KPA and ___K)
The enthalpy change when one mole of ions in the gaseous state or dissolved in water to infinite dilution standard conditions (100KPA and 293K)
