There are two reactants in a chemical equation, and one product. The mass of the product is 30g. The mass of the first reactant is 17g. What must the mass of the second reactant be, if the equation is to follow the law of conversation of mass?

Apiece of copper has a temperature of 75.6 0c. when the metal is placed in 100.0 grams of water at 19.1 0c, the temperature rises by 5.5 0c. what is the mass of the metal?

Ahypothesis must be testable and falsifiable to be considered scientific a. trueb. false

Which statement about hf is true? it is zero for any compound in its standard state. it is positive when the bonds of the product store more energy than those of the reactants. it is negative when a compound forms from elements in their standard states. it is zero for any element that is in the liquid state.