1. If forming new bonds releases energy, how can a reaction ever be endothermic? 2. Metal A has a heat capacity of 0.450 J/g°C while metal B has a heat capacity of 1.250 J/g° C. If both metals are supplied with 1000.0 J of energy, which one will heat up more? Explain by describing what specific heat capacity defines (i.e. more than "this number is bigger/smaller"). 3. When there is going to be a frost in Florida, farmers will spray their crops with water before the frost hits thereby preventing the fruit from freezing. Using concepts from this unit, explain why this helps to save the fruit. Curriculum Expectation D2. investigate and analyse energy changes and rates of reaction in physical and chemical processes, and solve related problems; 1. When 2.35g Mg(OH)2 is added to 250.0 mL of water, the temperature of the water raises from 20.5°C to 36.0°C. Calculate the molar enthalpy of solution.

1. If forming new bonds releases energy, how can a reaction ever be endothermic? 2. Metal A has a heat capacity of 0.450 J/g°C while metal B has a heat capacity of 1.250 J/g° C. If both metals are supplied with 1000.0 J of energy, which one will heat up more? Explain by describing what specific heat capacity defines (i.e. more than "this number is bigger/smaller"). 3. When there is going to be a frost in Florida, farmers will spray their crops with water before the frost hits thereby preventing the fruit from freezing. Using concepts from this unit, explain why this helps to save the fruit. Curriculum Expectation D2. investigate and analyse energy changes and rates of reaction in physical and chemical processes, and solve related problems; 1. When 2.35g Mg(OH)2 is added to 250.0 mL of water, the temperature of the water raises from 20.5°C to 36.0°C. Calculate the molar enthalpy of solution.

Chemistry: Matter and Change

1st Edition

ISBN:9780078746376

Author:Dinah Zike, Laurel Dingrando, Nicholas Hainen, Cheryl Wistrom

Publisher:Dinah Zike, Laurel Dingrando, Nicholas Hainen, Cheryl Wistrom

Chapter15: Energy And Chemical Change

Section15.1: Energy

Problem 7SSC

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