How much energy (in KJ) is required to convert 50.0g of ice at – 30 ˚C to steam at130˚C.

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Heat of fusion: Hf = 334 J/g, Q = m. Hf
Heat of vaporization: Hv = 2260 J/g, Q = m. Hv
2.1 J/g˚C Heat capacity (S) of solid water Q = m. S. ΔT
2.03 J/g˚C Heat capacity (S) of water vapor Q = m. S. ΔT
4.18 J/g˚C Heat capacity (S) of liquid water Q = m. S. ΔT

1) how many electrons are in each energy level of the following elements? a. he b. na c. na d. ne 2) how many valence electrons are percent in the following atoms? a. s b. mg c. be d. cl 3) which of the following elements are stable as atoms? a. he b. o c. cl d. ar if you are able to provide the work as to how you got the answers that would be greatly appreciated. : )

Which part of earth’s surface receives the most direct rays from the sun? a) equator b) ocean c) poles d) mountains

Once similarity and one difference between a mixture of elements and a mixture of compounds