Answer:
8
Explanation:
The duckweed is highest at pH of 8.
- Hope that helped! Please let me know if you need further explanation.
8 valence electrons means that the element is stable. When we hear stable, we know the group to look at! Noble gases all have 8 valence electrons making them stable and have a full octet.
Here are some:-
Krypton
Argon
Neon
A stock solution is a solution of a known concentration. Stock solution has a high concentration and therefore, the known amount of stock solution is used for preparing different concentrations, by diluting the same with the known amount of the solvent being used, such as water.
I believe that the best answer for this question is that the scanning tunneling microscope allowed scientists to create pictures of individual atoms. The scanning tunneling microscope is able to image surfaces' atoms. Its invention in 1981 was so monumental that it led to its creators winning the Nobel Prize in Physics. Hope this helps.
<u>Answer:</u> The given example is a physical change.
<u>Explanation:</u>
A chemical change is defined as the change in which chemical composition of a substance changes and results in the formation of a new substance. These are usually irreversible process.
A physical change is defined as the change in which only the shape and size of the substance changes and no new substance is formed. Only phase change occurs in these processes. These are usually considered as a reversible change.
For the given example: Moisture in the air forms beads of water on a cold window pane.
This is a physical change because water was initially present in the gaseous state (Moisture in the air) and when it is coming in contact with the cold window pane, the gaseous state of water gets converted into a liquid state.
Hence, the given example is a physical change.