How many joules are absorbed by 30.0 g of water when its temperature is raised by 20.0 °C?

Which formula can be used to calculate the molar mass of ammonia (nh3)? molar mass of n + molar mass of h 3 × molar mass of n + molar mass of h molar mass of n + 3 × molar mass of h 3 × molar mass of n + 3 × molar mass of h

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How do you know when a chemical reaction has occurred