Which device is designed to produce mechanical energy?
Well, mechanical energy is the sum of potential and kinetic energy. Kinetic energy is a unit of energy in which is the reason why an object does movement, while potential energy is another unit of energy in which is the reason why an object doesn't move, or stops. While you can stop a fan or a lamp, it isn't automatic. It's manually. So the answer is (4) an oven because mechanical energy happens automatically, not manually, or for a greater reason.
Explanation:
The limiting reagent (or limiting reactant or limiting agent) in a chemical reaction is a reactant that is totally consumed when the chemical reaction is completed. The amount of product formed is limited by this reagent, since the reaction cannot continue without it.
Answer: 
for the given reaction is 130.19kJ/mol
Explanation:
To Calculate the , we use the formula:
For the given chemical reaction:
We are given:
Now, to calculate , we put the values in the above equation:
As, the value of 
comes out to be positive, the reaction is said to be non-spontaneous reaction.
Cation means a positively charged ion. Anion is a negative one
Answer:
1 - 5 is in the link, 6 is below
Explanation:
https://elemscience.jordandistrict.org/wp-content/uploads/sites/8/6.4.4.5.2-Return-of-the-Buttercup-Answers.pdf
6. The autumn buttercup only occurs in the Sevier River Valley in western Garfield County, Utah. The elevation range for the species is 6,374 - 7,000 feet.
