BTEC UNIT 5 DATA MODELLING
ASSIGNMENT 2 AND 3 LEARNING AIM B
AND C EXAMINATION TEST 2026
COMPLETE QUESTIONS AND SOLUTIONS
⩥ Enthalpy of Formation (∆Hf). Answer: The enthalpy change that
occurs when one mole of a substance is formed from its elements in their
standard states under standard conditions
⩥ Enthalpy. Answer: The thermal energy stored in a chemical system. It
is defined by:
Enthalpy = Internal energy of the system + (pressure x volume)
H = U + pV
⩥ What is Hess' Law?. Answer: The enthalpy change is independent of
the route taken
⩥ Enthalpy of hydration (ΔHhyd). Answer: The enthalpy change that
occurs when one mole of gaseous ions is dissolved in water to make an
infinitely dilute solution under standard conditions
, ⩥ What factors affect the enthalpy of hydration?. Answer: Size of the
ion
Charge of the ion
⩥ Define the term, amphoteric. Answer: Can act as an acid and a base
⩥ Acid. Answer: a compound that contains one or more hydrogen atoms
and produces hydrogen ions when dissolved in water
⩥ Base. Answer: A compound that reacts to form a salt and water
⩥ Alkali. Answer: A base that dissolves in water forming OH- ions
⩥ Aluminium oxide reacts with hot hydrochloric acid to produce....
Answer: Aluminium chloride and water
⩥ Aluminium oxide reacts with bases such as sodium hydroxide to
form.... Answer: Aluminates
⩥ Why is the oxide ion strongly basic?. Answer: Because it has a very
small size and a high (2-) charge
ASSIGNMENT 2 AND 3 LEARNING AIM B
AND C EXAMINATION TEST 2026
COMPLETE QUESTIONS AND SOLUTIONS
⩥ Enthalpy of Formation (∆Hf). Answer: The enthalpy change that
occurs when one mole of a substance is formed from its elements in their
standard states under standard conditions
⩥ Enthalpy. Answer: The thermal energy stored in a chemical system. It
is defined by:
Enthalpy = Internal energy of the system + (pressure x volume)
H = U + pV
⩥ What is Hess' Law?. Answer: The enthalpy change is independent of
the route taken
⩥ Enthalpy of hydration (ΔHhyd). Answer: The enthalpy change that
occurs when one mole of gaseous ions is dissolved in water to make an
infinitely dilute solution under standard conditions
, ⩥ What factors affect the enthalpy of hydration?. Answer: Size of the
ion
Charge of the ion
⩥ Define the term, amphoteric. Answer: Can act as an acid and a base
⩥ Acid. Answer: a compound that contains one or more hydrogen atoms
and produces hydrogen ions when dissolved in water
⩥ Base. Answer: A compound that reacts to form a salt and water
⩥ Alkali. Answer: A base that dissolves in water forming OH- ions
⩥ Aluminium oxide reacts with hot hydrochloric acid to produce....
Answer: Aluminium chloride and water
⩥ Aluminium oxide reacts with bases such as sodium hydroxide to
form.... Answer: Aluminates
⩥ Why is the oxide ion strongly basic?. Answer: Because it has a very
small size and a high (2-) charge
