Li metal has a high capacity (3.82 Ah/g) and energy density (11,972 Wh/Kg).

Chemical energy is released or absorbed from reactions in various forms. The most easily measurable form of energy comes in the form of heat, or enthalpy. The enthalpy of a reaction can be calculated from the heats of formation of the substances involved in the reaction: ΔΗn = ΣηΔΗ; (products) – Σπ.ΔΗ (reactants) where n represents the stoichiometric coefficients. Part A Calculate the standard enthalpy change for the reaction Use the following data: ΔΗ; Substance (kJ/mol) A B C D ΔΗ; = -237 -385 205 -515 Submit Express your answer to three significant figures and include the appropriate units. ► View Available Hint(s) μА Value Previous Answers 2A + B2C + 2D Review | Constants I Periodic Table Units ?

2,4-Dichlorophenoxyacetic acid ("2,4-D") is a widely used herbicide with the molecular formula C8H6Cl2O3C8H6Cl2O3. The pKapKa of 2,4-D is 2.73. A certain water-based herbicide product contains 130 gL−1gL−1 of 2,4-D.   What is the pHpH of the 2,4-D solution?

A home swimming pool contains 156 m3 of water. At the beginning of swimming season, the water must be heated from 20.0°C to 30.0°C. a) How much energy (in kJ) must be supplied? b) If a natural gas heater supplies this energy with an 75.3 % heat transfer efficiency, how many grams of methane must be burned? (The heat of combustion of methane is -803 kJ/mol.)

A particular frost-free refrigerator uses about 790 kWh of electrical energy per year.   - Express this amount of energy in kilojoules (kJ). - Express this amount of energy in Calories (Cal).   - Express this amount of energy in joules (J).

What mass of natural gas (CH,) must you burn to emit 327 kJ of heat? CH4(g) + 2O2(g) → CO2(g) + 2H2O(g) ΔHxn = −802.3 kJ Express the mass in grams to three significant figures. m= [ΨΕΙ ΑΣΦ Ć ? 80

Carbohydrates serve as a vital source of chemical energy to the human body. Carbohydrates are broken down into smaller units of glucose, among other sugars, providing energy to various muscles and organs, including the brain. On average, for every 9.00 g of carbohydrates consumed, the body will store 153 kJ of energy. Convert this energy value to kilocalories (kcal). 153 kJ = kcal