IB Chemistry Topic 4

Which expression gives the enthalpy change, ΔH, for the thermal decomposition of calcium carbonate?

• ΔH = ΔH1 − ΔH2

• ΔH = 2ΔH1 − ΔH2

• ΔH = ΔH1 − 2ΔH2

• ΔH = ΔH1 + ΔH2

Tags

NGSS.HS-PS1-4

When four moles of aluminium and four moles of iron combine with oxygen to form their oxides, the enthalpy changes are –3338 kJ and –1644 kJ respectively. 4Al(s)+3O2(g)→2Al2O3(s): ΔH=−3338 kJ 4Fe(s)+3O2(g)→2Fe2O3(s): ΔH=−1644 kJ What is the enthalpy change, in kJ, for the reduction of one mole of iron(III) oxide by aluminium? Fe2O3(s)+2Al(s)→2Fe(s)+Al2O3(s)

• +1694

• +847

• -847

• -1694

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-4

NGSS.HS-PS3-1

• -214

• -72

• +72

• +214

Tags

NGSS.HS-PS1-4

•  [(−x) + (−y)] − (−z)

• (−z) − [(−x) + (−y)]

•  [(−2x) + (−3y)] − (−z)

• (−z) − [(−2x) + (−3y)]

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-1

• −144 + 11

• +144 − 11

• −144 − 11

• +144 + 11

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-4

• −1 × (+180) + −1 × (+112)

• −1 × (+180) + 1 × (+112)

• 1 × (+180) + −1 × (+112)

• 1 × (+180) + 1 × (+112)

Tags

NGSS.HS-PS1-4

What is the standard enthalpy change, in kJ, for the following reaction? C(s)+\frac{1}{2}O_2(g)→CO(g)

• -677

• -111

• +111

• +677

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-1

What is the enthalpy change of the reaction below?

• x + y + z

• x + y + z 

• 2x + 2y + z 

• 2x + 2y + 2z

Tags

NGSS.HS-PS1-4

• The standard enthalpy change of combustion of H2(g)

  is −286 kJmol−1.

• The standard enthalpy change of combustion of H2(g)

  is +286 kJmol−1.

• The standard enthalpy change of formation of H2O(l)

  is −572 kJmol−1. 

• The standard enthalpy change of formation of H2O(l)

  is +572 kJmol−1.

Tags

NGSS.HS-PS1-4

Which is correct for the reaction?

• Reactants are less stable than products and the reaction is endothermic.

• Reactants are more stable than products and the reaction is endothermic.

• Reactants are more stable than products and the reaction is exothermic.

• Reactants are less stable than products and the reaction is exothermic.

Tags

NGSS.HS-PS1-4