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:
5%
Explanation:
Given parameters:
Volume of original acetone before dilution = 10ml
Volume of diluted solution = 200ml
Unknown:
Percent volume of acetone in the solution = ?
Solution:
To find the percent volume of acetone in the diluted solution, use the expression below;
Percent volume of acetone = 
Insert the parameters and solve;
Percent volume of acetone =
x 100 = 5%
Answer:
D. The time of day
Explanation:
The independent variable is the variable the experimenter changes or controls and is assumed to have a direct effect on the dependent variable