Answer: X is a Solid; Y is a Gas
Explanation:
There are three (3) states of matter. They are: Solid, Liquid and Gases.
Substance X and Y, belong to the states of matter.
A Solid is a substance that retains its SIZE and SHAPE without need of a container (as opposed to a liquid or gas).
Thus, it will most likely be concluded that: substance X is a Solid; while Y is a Gas
There are 3 sig figs. 8 and 2 are obvious. The ending 0 is significant because it is at the end of a decimal number, and doesn't have to be measured.
At STP (standard temperature and pressure conditions), 1 mol of any gas occupies 22.4 L
This rule is applied to O₂
22.4 L volume occupied by 1 mol
Therefore 83.4 L occupied by - 1/ 22.4 x 83.4 = 3.72 mol
stoichiometry of O₂ to H₂O is 1:2
then the number of moles of water produced - 3.72 mol x 2= 7.44 mol
mass of water produced - 7.44 mol x 18.01 g/mol = 134.1 g
correct answer is D
Answer:
6.791
Explanation:
For proper significant figures with addition, you would use the significant figures of the number with lowest decimal place. 6.298 goes to the 10⁻³ place. 0.492712 goes to the 10⁻⁶ place. You will go out to the 10⁻³ place.
6.298 + 0.492712 = 6.790712 ≈ 6.791
Cooks should use sea salt in recipes instead of regular table salt.
