25cm3 of a 0.4M sodium hydroxide solution was diluted into 250cm3 of water. What is the molarityof the resultant solution.

0.04 M

Explanation:

From the question given above, the following data were obtained:

Initial volume of solution (V1) = 25 cm³

Initial Molarity of solution (M1) = 0.4 M

Final volume of solution (V2) = 250 cm³

Final Molarity of solution (M2) =?

We can obtain the final Molarity of the solution by using the dilution formula as illustrated below:

M1V1 = M2V2

0.4 × 25 = M2 × 250

10 = M2 × 250

Divide both side by 250

M2 = 10/250

M2 = 0.04 M

Therefore, the resulting molarity of the diluted solution is 0.04 M

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e