After chemical weathering, the chemical makeup of the weathered rock, is the same as the original, or different?

2. how is heavy water different from normal water

An object of mass 10.0 kg and volume 1000 ml and density 10 g/ml sinks in water who’s density is 1.0 g/ml. what is the mass of the water which has been displaced in kilograms

8. how much enthalpy/heat is transferred when 0.5113gof ammonia (nh3) reacts with excess oxygen according| to the following equation: 4nh3 +502 - 4n0+ 6h20ah = -905.4j