Answer:
protons = atomic numbermass number = protons + neutronsatomic number = mass number - neutrons = 78-38 = 40
Explanation:
Hot and cold water can be mixed together to make warm water is the correct statement that shows role of chemistry.
<h3>
What demonstrates the role of chemistry?</h3>
Hot and cold water can be mixed together to make warm water is the statement that demonstrates the role of chemistry in getting ready for school in the morning because it describes the features of warm water. It also shows the method of getting warm water from mixing of hot and cold water.
So we can conclude that Hot and cold water can be mixed together to make warm water is the correct statement that shows role of chemistry.
Learn more about mixture here: brainly.com/question/24647756
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Answer: D. An increase in entropy
Explanation:
Entropy is the measure of randomness or disorder of a system. If a system moves from an disordered arrangement to an ordered arrangement, the entropy is said to increase and vice versa.
For a reaction to be spontaneous, the enthalpy of the solution must decrease and the entropy must increase.
To overcome a positive enthalpy of solution and allow a solid solute to dissolve in water, an increase in entropy would make the reaction spontaneous as the system would move to a more disordered state.
Gravity pulling the mass of the atmosphere toward the center of the
earth. Atmosphere includes air, water vapor, etc.
It would be a physical change. It’s still water just in a different physical form. If it was a chemical change, it would no longer be water. For example, when the ice melts back into water...it’s still water.
