Answer:
<h3>F=4k.gm/s^2</h3>
Explanation:
<h3>F=m×a</h3><h3>f=2k.g×2m/s^2</h3><h3>f=4k.gm/s^2</h3>
An endothermic reaction needs energy to proceed, such energy is usually taken from the environment surrounding the reaction. In the typical case this energy is expressed as heat. Heat is an state of atomic activity, that energy is transferred to an ENDOthermic reaction so the initial threshold of reaction is overcome and the final reaction can occur.
Answer:
The final volume is 6.4 L.
Explanation:
Dilution is reducing the concentration of a chemical and is achieved by adding more solvent to the same amount of solute. In other words, dilution is the procedure that is followed to prepare a less concentrated solution from a more concentrated one, and it simply consists of adding more solvent.
In a dilution the amount of solute does not vary, and as only more volume (and mass) of solvent is being added, the concentration of the solute decreases.
In a dilution the expression is used:
Ci*Vi = Cf*Vf
where:
- Ci: initial concentration
- Vi: initial volume
- Cf: final concentration
- Vf: final volume
In this case:
- Ci: 8 M
- Vi: 2 L
- Cf: 2.5 M
- Vf: ?
Replacing:
8 M* 2 L= 2.5 M* Vf
Solving:

Vf=6.4 L
<u><em>The final volume is 6.4 L.</em></u>
If the ending substance has changed its properties. For example if iron rusts it is a chemical change because it is no longer the same as before it is now just rust. A physical change only changes the appearance but burning something or changing it's chemical properties is a chemical change.
Answer:
The electrons in an atom move around the nucleus in regions known as electron shells.