Energy Change in Reactions - Page 4
Questions
- How much heat must be removed to freeze a tray of ice cubes at 0°C if the water has a mass of 225 g?
- Why is change in enthalpy zero for isothermal processes?
- 25.5 g of liquid Benzene (#C_6H_6#) loses 200 J of heat as it cools. What is the temperature decrease?
- What process transfers heat by moving particles from one place to another?
- Indicate whether each of the ff. reactions is exothermic or endothermic? a) Br2(l)+Cl2(g)→2 BrCl(g) Δ H=29.4kJ
- Why do endothermic reactions happen?
- What chemical reactions release energy?
- What is one example of change of energy?
- Is condensing water vapor an exothermic process or an endo process?
- How do you calculate the energy released when 24.8 g #Na_2O# reacts in this reaction: #Na_2O(s) + 2HI(g) -> 2Nal(s) + H_2O(l)#?
- What happens to the kinetic energy of its molecules as ice melts into water?
- How to treat stretch bond to calculate its enthalpy and entropy contribution?
- Why is the joule, the SI unit of energy, also the appropriate unit for measuring heat?
- How do you find q for isothermal processes?
- Is the entropy change positive or negative for this reaction? #2KClO_4(s) -> 2KClO_3(s) + O_2(g)#
- Given the balanced equation representing a reaction: #2NaCl -> 2Na + Cl_2#. What must happen to energy in the reaction to break the bonds in NaCl?
- How do you calculate the energy absorbed when #2.0x10^3g# of ice (#CO_2#) sublimate at the normal dry sublimation point? The enthalpy of sublimation 196.3J/g.
- Why are lakes and oceans are able to stabilize air and land temperatures?
- Is the synthesis of ozone, #O-3#, from oxygen, #O_2#, an example of an exothermic or endothermic reaction?
- Is paper burning with a bright flame endothermic or exothermic? Plastics becoming brittle after being left in the sun? A firecracker exploding?