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A coffee-cup calorimeter contains 100.0 mL of 1.000 M HCl (excess) at 20.3 °C. When 1.82 g Zn(s) is added, the temperature rises to 30.5 °C. What is the heat of reaction per mol Zn? Assume that the heat of solution is that of water, and the density of the HCl is 1.000 g/mL.   Zn(s)  + 2 HCl(aq)  → ZnCl2(aq)  + H2(g)   

When you look out the window at the blue sky you see light of a wavelenth of  473 nm. A photon of that light has a frequency of [a]Hz and an energy of [b] J. Must show your work (scratch paper) to receive credit.  

A coffee-cup calorimeter contains 100.0 mL of 1.000 M HCl (excess) at 20.3 °C. When 1.82 g Zn(s) is added, the temperature rises to 30.5 °C. What is the heat of reaction per mol Zn? Assume that the heat of solution is that of water, and the density of the HCl is 1.000 g/mL.   Zn(s)  + 2 HCl(aq)  → ZnCl2(aq)  + H2(g)   

Use Hess’s Law and the following data   CH4(g) + 2 O2(g) → CO2(g)   +  2 H2O(g) ΔH = −802 kJ CH4(g) + CO2(g) → 2 CO(g)   +  2 H2(g) ΔH = + 247 kJ CH4(g) + H2O(g) → CO(g)   +  3 H2(g) ΔH = + 206 kJ   to determine the ∆H°rxn for the following reaction, an important source of hydrogen gas:   2 CH4(g) + O2(g) →  2 CO(g)   +  4 H2(g)   Must show your work (scratch paper) to receive credit.

Given the data:  N2H4(l) + O2 (g) → N2(g) + 2 H2O (l) ΔH° = – 622.2 kJ 2 H2(g) + O2 (g) → 2H2O (l) ΔH° = -571.6 kJ H2(g) + O2 (g) → H2O2(l) ΔH° = – 187.8 kJ   using Hess’s Law the ∆H for the reaction below is [a] kJ:N2H4 (l) + 2 H2O2 (l) → N2(g) + 4 H2O (l)Must show your work (scratch paper) to receive credit.

When a 2.150-g sample of glucose, C6H12O6, is burned in a bomb calorimeter with a heat capacity of 6.317 kJ/°C, the temperature of the calorimeter increases from 23.446°C to 28.745°C. Calculate ∆E for the combustion of glucose in kJ/mol.

When a 2.150-g sample of glucose, C6H12O6, is burned in a bomb calorimeter with a heat capacity of 6.317 kJ/°C, the temperature of the calorimeter increases from 23.446°C to 28.745°C. Calculate ∆E for the combustion of glucose in kJ/mol.

Given the following equations and ∆H° values:                                                               OF2(g) + H2O(l) → O2(g) + 2 HF(g) ∆H° = -276.6 kJ SF4(g) + 2 H2O(l) → 4 HF(g) + SO2(g) ∆H° = -827.5 kJ S(s) + O2(g) → SO2(g) ∆H° = -296.9 kJ  determine the heat of reaction (kJ) at 298 K for the reaction:  2 OF2(g) + 2 S(s) →SO2(g) + SF4(g) Must show your work (scratch paper) to receive credit.

Use the standard enthalpies of formation provided to calculate the change in enthalpy for the reaction below: 5 CO(g)  +  11 H2(g) → C5H12(l)   + 5 H2O(l)      ΔH°f (kJ/mol) CO(g)  – 110.5 H2O(l)  – 285.8 C5H12(l)    – 146.8 Must show your work (scratch paper) to receive credit.

A typical television remote control emits radiation with a wavelength of 940 nm. A photon of that light has a frequency of [a]Hz and an energy of [b] J. Must show your work (scratch paper) to receive credit.