The whitening toothpastes showed differences in their physical-chemical properties. All toothpastes promoted changes to the surface, probably by the use of a bleaching agent.
Answer: b. is positive and is positive.
Explanation:-
As the temperature of the pack drops, the energy has been absorbed from the pack for dissolution of in water. Thus as the energy has been absorbed in the reaction, the reaction is endothermic and the change in enthalpy i.e. is positive.
The entropy is the measure of degree of randomness. The entropy increases when the randomness increases and the entropy decreases when the randomness decreases. When a substance dissolves in water, it dissociate into ions and hence the randomness increases thus the change in entropy i.e. is positive.
Most likely the equation yields a new compound XY. This is a synthesis reaction. <span>Synthesis
reaction is a reaction where two or more substances combine to form a new
compound. It is a reaction which releases energy in the form of heat and
light. Therefore, it is an exothermic reaction.</span>
Answer:
A neutralized solution in chemistry refers to the reaction between an acid and base that results in a neutral balance, or a measure of 7 on the pH scale.
Explanation:
Answer:
True
Explanation:
The evidence for evolution is found at all levels of organization in living things and in the extinct species we know about through fossils.