Answer:
in lewis structure, a solid line is usually used to represent a bond between the atoms
Explanation:
the dots that are shown around the atom represent the valence electrons on the outer shell
when there are multiple atoms, either a pair of dots circled (one dot from each atom) or a solid line is used to show the bonds between those atoms
A stratovolcano is a tall, conical volcano composed of one layer of hardened lava, tephra, and volcanic ash. These volcanoes are characterized by a steep profile and periodic, explosive eruptions. The lava that flows from them is highly viscous, and cools and hardens before spreading very far. , , !!
The question is incomplete, here is the complete question:
Consider the following reaction: 
In the first 15.0 s of the reaction, 1.9×10⁻² mol of O₂ is produced in a reaction vessel with a volume of 0.480 L . What is the average rate of the reaction over this time interval?
<u>Answer:</u> The average rate of appearance of oxygen gas is 
<u>Explanation:</u>
We are given:
Moles of oxygen gas = 
Volume of solution = 0.480 L
Molarity is calculated by using the equation:
So, 
The given chemical reaction follows:
The average rate of the reaction for appearance of 
is given as:
![\text{Average rate of appearance of }O_2=\frac{\Delta [O_2]}{\Delta t}](https://tex.z-dn.net/?f=%5Ctext%7BAverage%20rate%20of%20appearance%20of%20%7DO_2%3D%5Cfrac%7B%5CDelta%20%5BO_2%5D%7D%7B%5CDelta%20t%7D)
Or,
where,
= final concentration of oxygen gas = 0.0396 M
= initial concentration of oxygen gas = 0 M
= final time = 15.0 s
= initial time = 0 s
Putting values in above equation, we get:
Hence, the average rate of appearance of oxygen gas is
Sir James Chadwick was the scientist who discovered the neutron. The electron and proton had already been found but with the neutron known, we knew everything that made up our universe. He won the 1935 Nobel Peace Prize for his discovery.
