When 50 ml (50 g) of 1.00 m hcl at 22oc is added to 50 ml (50 g) of 1.00 m naoh at 22oc in a coffee cup calorimeter, the temperature increases to 28.87oc. how much heat is produced by the reaction between hcl and naoh? (the specific heat of the solution produced is 4.18 j/goc)?

Explanation:

HCl + NaOH ⟶ NaCl + H₂O

There are two energy flows in this reaction.  

Heat of reaction + heat to warm water = 0  

           q₁             +              q₂                 = 0  

           q₁             +          mCΔT              = 0  

Data:

    m(HCl) = 50 g

m(NaOH) = 50 g

           T₁ = 22       °C

          T₂ = 28.87 °C

           C = 4.18 J·°C⁻¹g⁻¹

Calculations:

 m = 50 + 50 = 100 g

ΔT = 28.87 – 22 = 6.9 °C

 q₂ = 100 × 4.18 × 6.9 = 2900 J

q₁ + 2900 = 0

q₁ = -2900 J

The negative sign tells us that the reaction produced heat.

The reaction produced .

a 20-cm-long, cylindrical graphite (pure carbon) rod is inserted into an oxidizing atmosphere at 1145 k and 1.013 x 105 pa pressure. the oxidizing process is limited by the diffu- sion of oxygen counterflow to the carbon monoxide that is formed on the cylindrical surface.