Answer:
open system
Coffee held in a cup is an open system because it can exchange matter water vapors and energy heat with the surroundings.
Answer:
When a large, fissile atomic nucleus such as uranium-235 or plutonium-239 absorbs a neutron, it may undergo nuclear fission. The nucleus splits into two or more lighter nuclei, releasing kinetic energy, gamma radiation, and free neutrons.
Explanation:
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Answer:
HNO₃.
Explanation:
- It is known that acids decrease the pH of the solution, while bases increase the pH of the solution.
So, HF and HNO₃ decrease the pH of the solution as they produce H⁺ in the solution.
<em>While, KOH and NH₃ increase the pH of the solution as they produce OH⁻ in the solution.</em>
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HNO₃ will decrease the pH of the solution greater than HF.
- Because HNO₃ is strong acid that decomposes completely to produce H⁺ more than the same concentration of HF that is a weak acid which does not decomposed completely to produce H⁺.
Chemical change can be determined when a substance change it's state of composition and is irreversible. Five evidences that chemical change has occured are, color change, formation of a precipitate, formation of gas, odor change, temperature change. Examples of chemical change are, combustion reactions, rusting iron, precipitate of AgCl.
