Answer:
Phase changes that require a loss in energy are condensation and freezing.
Explanation:
Answer:
This is a chemical change because it has been lit on fire. When it is lit on fire, the fire has been made, heat has been made, and gasses produced from the fire have also been made. Because this introduces new matter to the pictures, it is a chemical reaction.
Explanation:
The rate of a chemical reaction is affected by temperature, Catalysts, Suface area, Concentration.
<h3>Rate of reaction</h3>
The rate of a chemical reaction is the rate at which the concentration of reactant molecules decreases or the concentration of product molecules increases.
<h3>Factors effecting rate of chemical reaction </h3>
The factors that affect the rate of chemical reaction include:
- Temperature: increase in temperature increases reaction rate while decrease in temperature decreases reaction rate.
- Catalysts: the present of catalysts increase the reaction rate. Some catalysts decreases reaction rate and are known as negative catalysts.
- Surface area: increase in surface area of reactants increases reaction rate.
- Concentration: Increase in concentration of reactants increases reaction rate while decrease in concentration of reactants decreases reaction rate.
Therefore, the rate of a chemical reaction is affected by temperature, Catalysts, Suface area, Concentration.
Learn more about rate of reaction and factors affecting reaction rate at: brainly.com/question/15841605
Explanation:
Helium exists in three different forms due to the phenomenon of isotopy. Isotopy is the existence of two or more atoms of the same element having the same atomic number but different mass numbers due to the differences in the number of neutrons in their nuclei.
- The atoms of these elements are called isotopes.
- This is why Helium can exist in three different forms.
- Isotopes have the same electronic configuration but with the same chemical properties.
Learn more:
isotopes brainly.com/question/1915462
Isotopy brainly.com/question/2593342
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Answer:
Potential energy is the stored energy of position possessed by an object.
