Another reaction that is used to propel rockets is
This reaction has the advantage that neither product is toxic, so no dangerous pollution is released. When the reaction consumes 10.0 g liquid N2O4, it releases 124 kJ of heat.
- (a) Is the sign of the enthalpy change positive or negative?
- (b) What is the value of ΔH for the chemical equation if it is understood to be written in molar quantities?
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Chemistry: Principles and Practice
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- Hydrogen peroxide, H2O2, is a colorless liquid whose solutions are used as a bleach and an antiseptic. H2O2 can be prepared in a process whose overall change is H2(g)+O2(g)H2O2(l) Calculate the enthalpy change using the following data: H2O2(l)H2O(l)+12O2(g);H=98.0kJ2H2(g)+O2(g)2H2O(l);H=571.6kJarrow_forwardWhich of the following substances have an enthalpy of formation equal to zero? a. Cl2(g) b. H2(g) c. N2(l) d. Cl(g)arrow_forwardWhat mass of acetylene, C2H2(g), must be burned to produce 3420 kJ of heat, given that its enthalpy of combustion is 1301 kJ/mol? Compare this with the answer to Exercise 5.91 and determine which substance produces more heat per gram.arrow_forward
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