How many moles are in 425.0 g of sodium chloride?

An alloy contains 66 g of pure zinc. what is the percentage of zinc in the alloy? express your answer to two significant figures and include the appropriate units.

The activation energy for the reaction no2(g)+co2(g)⟶no(g)+co(g) is ea = 300 kj/mol and the change in enthalpy for the reaction is δh = -100 kj/mol . what is the activation energy for the reverse reaction?

In an exothermic reaction, energy may be released to the surroundings in the form of question 4 options: heat light thermal all of the above