Pick 2 Final Project

By; Stephen Nachazel 2nd period

Experiments that can be used with a Balance.

Gravimetric analysis experiments can be conducted with an electronic balance. In a gravimetric analysis experiment, a solution is produced from mixing compounds and then contained in a beaker or a flask. The balance is used to weigh the filtration paper before the precipitate forms on the paper and then, once the solution is poured through the filter paper, it is weighed once more to find the mass of the precipitate and filter paper. From this, it can be determined what the mass of the precipitate is which is then used to determine the percent yield of the experiment.

Another experiment which uses a balance is a percent composition experiment. In this sort of experiment, an alloy is massed using the balance and then the data recorded. The alloy is then dissolved using an acid which produces products. The products are then analyzed using stochiometry and from these data points, it is possible to determine what the alloy is made out of and the relative percentages of how much of one substance is in the alloy. A commonly used alloy is brass, which is often composed of copper and zinc with other occasional metals being present in it.

History

    • Balances have been around since the dawn of time and they always had the exact same purpose: to weigh things with.
    • used to be mechanical or counterweight, which is where the object being weighed was placed in a sling on one side and then weight was gradually added to the other side until the balance was level.
    • in the 1950’s electronic balances became available to public as there were advances made in the fields of computation and electrical engineering that allowed precise instruments to be mass produced at a low price.
    • ever since then, balances have become more and more accurate with the advent of microbalances( balances that can go to parts per million) and quartz crystal microbalances ( which use quartz crystals as a method of precision.

    Errors

    The main error that would result from misuse of the balance is that an inaccurate mass would be obtained, The main way to obtain an incorrect mass is to not zero the balance before using or not allowing the balance to stabilize once an object is added to the platform. This does not pose any danger to the user but it would cause issues with the accuracy of the experimentally determined mass. The main effect of this would be that the conclusion would not be as accurate as it should be, but other than that, there are not any serious consequences of not using the balance correctly.