Mercury is often used as an expansion medium in a thermometer. the mercury sits in a bulb on the bottom of the thermometer and rises up a thin capillary as the temperature rises. suppose a mercury thermometer contains 3.550 g of mercury and has a capillary that is 0.190 mm in diameter.
how far does the mercury rise in the capillary when the temperature changes from 0.0 degrees celsius to 25.0 degrees celsius? the density of mercury at these temperatures is 13.596 g/cm^3 and 13.534 g/cm^3, respectively.

gold is my favorite solid.

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.

the answer is b because, investigating whether another species of moth also drinks tears might be interesting, but it would not directly explain why this species of moth does.

to explain why this species of moth drinks tears, the scientist could ask: "what nutrients that moths need are in elephant tears? "

the scientist could experiment with moth repellent or oter ways to keep the moths away, but that would not answer his original question.