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What is the energy of a mole of photons of blue light with a wavelength of 458 nm?

Use the information provided to determine ΔH°rxn for the following reaction: CH4(g) + 3 Cl2(g) → CHCl3(l) + 3 HCl(g)        ΔH°rxn = ? Molecule  ΔH°f    (kJ/mol)   CH4(g)      -75CHCl3(l)   -134HCl(g)       -92

An endothermic reaction causes the surroundings to 

Calculate the energy, in joules, required to excite a hydrogen atom by causing an electronic transition from the n = 1 to the n = 4 principal energy level. 

Calculate the energy, in joules, required to excite a hydrogen atom by causing an electronic transition from the n = 1 to the n = 4 principal energy level. 

What is the energy of a mole of photons of blue light with a wavelength of 458 nm?

An 8.29 g sample of calcium carbonate [CaCO3 (s)] absorbs 50.3 J of heat, upon which the temperature of the sample increases from 21.1°C to 28.5°C. What is the specific heat of calcium carbonate (J/g°C)?

A 22.44 g sample of iron absorbs 180.8 J of heat, upon which the temperature of the sample increases from 21.1°C to 39.0°C. What is the specific heat of iron (J/g°C)?

Given the thermochemical equation: 2Cu2O(s) –> 4Cu(s) + O2(g)             ΔH= +333.8 kJ/mol Calculate the mass of copper produced when 1.47 x 104 kJ is consumed in this reaction.

Which cell secretes the hormone that promotes production of hydrochloric acid?