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define hydration enthalpy and given equation and states whether it is endothermic or exothermic

This is the enthalpy change when one mole of gases ions becomes hydrated and forms one mole of aqueous ions standard conditions

Na+ (g) → Na+ (aq)

exo

Why is hydration enthalpy exothermic?

Because there is electrostatic force of attraction between the polar water molecule and the NA plus ion

The NA + ion attracts the loan pair of electrons on the polar oxygen on the H2O molecule

Define entropy of solution and state an equation

Enthalpy change when one mole of an ionic solid dissolves in an amount of water large enough so that the dissolved ions are well separated and do not interact with each other

Nacl(s) → Na+(aq) + Cl-(aq)

Define lattice enthalpy of formation, state whether it is exothermic or endothermic and why and an equation

Entropy change when one mole of an ionic compound is formed from its constituent ions in the gas state

Exothermic because there is electrostatic forces of attraction between ions of opposite charge

K+(g) +F-(g) → KF(s)

Define lattice enthalpy of dissociation, state whether it is exothermic or endothermic and why and an equation

Entropy changed that occurs when one mole of an ionic compound is broken up into its constituent ions in the gas state

Endothermic as energy is needed to overcome the static force of attraction between ions of opposite charge

K+(g) +F-(g) ← KF(s)

Define perfect ionic model

Ions would be perfectly spherical and they would only be static forces of attraction between oppositely charged ions and no covalent characters

Define mean bond enthalpy

Energy required to break one mole of a covalent bond measured in the gas state averaged across many compounds

Define first ionisation enthalpy

The enthalpy change when one mole of electrons is removed from one mole of atoms in the gas state to produce one mole of gases Uni positive ions

Define first electron affinity and write an equation

And they'll be changed when one mole of gaseous atoms gains one mole of electrons to form one mole of gas is negative ions

O(g) + e- → O- (g)

is first electron affinity exothermic or endothermic and why?

Exothermic because the ion is more stable than the atom and there is an attractive force between the nucleus of the oxygen atom and an external electron

Define second electron affinity write an equation and state whether it's EXO or endothermic

The end they'll be changed when one mole of gaseous Uni negative ions gain one mole of electrons to form one mole of gas US di negative ions

It is endothermic as the Uni negative oxygen ion repels the electrons being added so energy is needed to overcome this repulsion

O-(g) +e- → O2-(g)

Define enthalpy of atomisation and write an equation

enthalpy change for the formation of one mole of gaseous atoms from an element in its standard state

Na(s) → Na(g)

0.5Cl2 (g) → Cl(g)

Define bond dissociation enthalpy and write an equation and state whether it is exothermic or endothermic

enthalpy change that occurs when one mole of a covalent bond in the gaseous state is broken into two gaseous atoms

Cl2(g) → 2Cl(g)

Endothermic as energy is needed to break the bond in one mole of chlorine molecules to form two moles of gaseous chlorine atoms

Explain why the hydration entropy of magnesium 2+ ion is much more exothermic than that of sodium plus ion

The magnesium ion is small and has a greater charge than the sodium ion so the magnesium ion has a greater electrostatic force of attraction for the loan pair of electrons on the Delta negative oxygen of the polar water molecule

Explain why the hydration of Cl minus is more exothermic than that of BR minus

The chloride ion is smaller despite the same charge as it has greater charge density so it has greater electric static force of attraction for the hydrogen delta positive on the polar water molecule

Why is sodium chloride more exothermic than potassium chloride?

The lattice formation of sodium chloride is more exothermic as the sodium ion is smaller than the potassium ion so it has a greater charge density so the chloride ion has a greater static force of attraction for the sodium ion

Porn hub cycles examples pages 11 to 14

Difference between the experimental and the theoretical lattice enthalpy of formation

Experimental entropy is calculated using the Bourne harbour cycle

The theoretical are calculated by a theoretical calculation that considers the size charge and arrangements of ions in the lattice which assumes that the structure is exhibiting the perfect ionic model

Nacl experimental = -771 theoretical = -766

States what can be concluded from these values

There is very little difference between the experimental and theoretical losses formation values which suggests the ionic compound exhibits the perfect ionic model and no covalent character characters are present

Al2O3 experimental = -15628 theoretical = -14928

States what can be concluded from these values

There is a significant difference between the experimental and theoretical value of lattice formation so this suggests the ionic compound exhibits lots of covalent character in molasses