Answer: 250 ml of stock solution with molarity of 12.0 M is measured using a pipette and 250 ml of water is added to volumetric flask of 500 ml to make the final volume of 500 ml.
Explanation:
According to the dilution law,

where,
= concentration of stock solution = 12.0 M
= volume of stock solution = ?
= concentration of diluted solution= 6.00 M
= volume of diluted acid solution = 500 ml
Putting in the values we get:


Thus 250 ml of stock solution with molarity of 12.0 M is measured using a pipette and 250 ml of water is added to volumetric flask of 500 ml to make the final volume of 500 ml.
Answer: Option (b) is the correct answer.
Explanation:
A synthesis reaction is the reaction in which two compounds or atoms combine together to result in the formation of a single compound.
For example, 
Thus, here CaO and
combine together to result in the formation of calcium carbonate compound. Therefore, it is a synthesis reaction.
Therefore, we can conclude that the most likely products of Cao + co2 → CaCO3 reaction.
The sun's energy would be circulated through convection. This is because whenever you see the word "circulate", there is a pretty good chance it has something to do with convection.