Answer: check for a change in total mass during a reaction.
According to the law of conservation of mass during a chemical change the total mass of the products remains equal to the total mass of the reactants: there is not change in the total mass.
During nuclear reactions the mass can change due to the huge release of energy which proceeds from mass change, as per the famous equation ΔE =Δm. c^2.
Answer:
The factors on which the amount of energy absorbed by an endothermic reaction depends are the " physical state of the reactant and the difference in the potential energy of the reactant and the product".
Explanation:
In an endothermic reaction the factors that affects the reaction are the physical state of the reactant, which thus becomes the enthalpy. And the difference in potential energy of the reactant because if the sum of the potential energy is less than the sum of the potential energy of the product than the endothermic reaction will be positive and the reaction hence will be endothermic.
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Answer:
b. It should be dumped in a beaker labeled "waste copper" on one's bench during the experiment.
d. It should be disposed of in the bottle for waste copper ion when work is completed.
Explanation:
Solutions containing copper ion should never be disposed of by dumping them in a sink or in common trash cans, because this will cause pollution in rivers, lakes and seas, being a contaminating agent to both human beings and animals. They should be placed in appropriate compatible containers that can be hermetically sealed. The sealed containers must be labeled with the name and class of hazardous substance they contain and the date they were generated.
It never should be returned to the bottle containing the solution, since it can contaminate the solution of the bottle.
In the Solutions and Spectroscopy experiments there is always wastes.
