Are phase changes a physical change or a chemical change? Example: My icecream cone melted in the hot sun.

Analyze how limestone is weathered and identify the features that are formed as a result of this dissolution

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Given the following information: mass of proton = 1.00728 amu mass of neutron = 1.00866 amu mass of electron = 5.486 × 10^-4 amu speed of light = 2.9979 × 10^8 m/s calculate the nuclear binding energy (absolute value) of 3li^6. which has an atomic mass of 6.015126 amu. j/mol.