Answer:
5.77% Error.
Explanation:
Given an experimental value of 275 g , and a theoretical value of 260 g, the percent error can be found using the equation:

% Error = ( | 260 - 275 | / 260 ) × 100 = ( | - 15 | / 260 ) × 100 = ( 15 / 260 ) × 100 = 1500/260 = 300 / 52 = 5.769230769230.. ≈ 5.77%
Answer:
••It's melting point equals -38.8 degrees Celsius because it is mercury. |••
Explanation:
This one makes the most sense out of the answers.
We know that the mass number (top number) must be 33 because the electron that is emitted has no mass. The atomic number (bottom number) must be 15, because it is one less than 16 and the electron has a negative charge. Therefore, the first box is the answer.
5. B air is a mixture of many elements, but is not a chemically fused.
6. B Beef stew, composition varies throughout.
7. A. They can be chemically separated into their component elements, but they are all homogenous, and as such, have constant composition, which differs from the components properties, as the components must undergo a chemical change to become compounds.