There are 3 possible ways of determining pH.
1. A pH meter, 2. Litmus paper/ pH test strips or 3. Titrations.
1. A pH meter works by sending a small electric current through the solution. An electrical current can only be created if there are free-moving particles such as H+ ions from an acid or OH- ions from a base. The pH meter can determine the pH by how high the conductivity is.
2. Litmus Paper or pH test strips are strips that turn a specific colour under a specific pH. This colour can then be compared to a colour chart which will tell you the pH. The downfall of this method is that the red ink will stain the strip and you will be unable to get an accurate reading.
3. A titration is the best method, if done properly, for determining pH.
Valence electrons are the electrons located in the outermost shell
Answer:
Highest energy will be equal to 
Explanation:
Charged on doubly ionized helium atom 
It is accelerated with maximum voltage of 3 MV
So voltage 
Now energy is given by 
So highest energy will be equal to
Answer:
Warm air rises, resulting in a decrease air pressure.
Explanation:
Tornado is the rapid and violent rotation of column of air which move from the thunderstorm to the ground.
It is formed when there is collision between warm and cold air. The cold air which is more sense than the warm air is pushed over the warm air which result in thunderstorms. The warm air then rises which result in decrease air pressure causing an updraft. The updraft then begin to rotate as there are variations in wind speeds and directions.
The atomic # and the mass #.
