Do not worry that you find these problems difficult; many students consider them to be the toughest problems in the course. In general, you just have to keep thinking about where the energy comes from and where it goes. For example, if a hot object is dropped in a calorimeter, it will cool down. Thus, it loses energy...
Many students have a difficult time understanding significant figures. It is a very important concept to master so keep trying if you find it to be challenging! Here are some things to keep in mind as you go: 1. Practice. You will get plenty of practice throughout the book, but if you are having particular trouble a...
Here is a sample calculation: **Data:** Mass of 50.0 mL vinegar: 51.0 g Number of mL of vinegar to reach endpoint: 23.0 mL **Calculations:** Density of vinegar: 51.0 g/ 50.0 mL = 1.02 g/mL Number of grams of vinegar added: (1.02 g/mL) x (23.0 mL) = 23.5 g Mass of C2H4O2 added: (23.5 g) x (0.0500) = 1.18...
The sample calculations are on pages 119-120 of the _Solutions and Tests Manual for Exploring Creation with Chemistry 3rd Ed._ ...
In the problem, you are told to add the numbers, so you will need to follow the rules on page 28 of the textbook for adding with significant figures. You will need to expand the number given in scientific notation before adding. Once you’ve added, you must use precision to determine where to round. When you look back...
The “hypo” prefix is really just a way of telling you how many oxygen atoms are in sodium hypochlorite. It means only one oxygen atom. Thus, sodium hypochlorite is NaOCl. That’s the main ingredient in bleach. The “hypo” distinguishes this chemical from sodium chlorite, which is NaClO2. When you mix bleach with ammoni...
In the chemistry experiments, the red cabbage is used to make a pH indicator. Red cabbage can be difficult to find internationally or during the winter, so if you are unable to purchase red cabbage, the link below has a detailed procedure for using other materials to make the same indicator. [Make Your Own Indicators...
Significant figures rules are only used for measurements, not constants. You should not have to worry about the number of digits for constants and neither should that affect your significant digit calculations. The rules listed on pages 21-25 of the Chemistry textbook state that they are for measurements only. ...
The blue substance you noticed forming on one terminal is copper hydroxycarbonate. It forms from the copper in the battery and the carbonate in the baking soda that was left over. It is the same stuff that turns copper statues (like the Statue of Liberty) a blue-green color. The chemical reaction that occurs to make ...
In the first part of this example, you have: (405 nm/1) x (10-9 m/1nm) When you multiply 405 by 10-9, you get 405 x 10-9 This is not standard scientific notation, because there is no decimal place in 405. To get it into scientific notation, move the decimal to the left 2 places. This decreases 405 by a factor of 10...