Answer:
Liquid volume is usually measured using either a graduated cylinder or a buret. As the name implies, a graduated cylinder is a cylindrical glass or plastic tube sealed at one end, with a calibrated scale etched (or marked) on the outside wall.
it is important to check the conductivity and pH of pure water to:
1- to check the purity of water and if it healthy or not , and the water source.
2- we have to measure the PH to know the alkalinity or acidity of water. If the PH > 7 so it is acidic , if PH < 7 so it is alkaline.
3- we have to measure the conductivity of the water as it is an indication for the impurity level. and it shouldn't be high to keep the water healthy.
The atomic masses written for every element in the periodic table is the average atomic weight that is calculated from the element's isotopes. The formula would be:
Average Atomic Weight = ∑(Isotope Mass×Relative Abundance)
Substituting the values:
Average Atomic Weight = (331 amu×0.35) + (337 amu×0.65)
Average Atomic Weight = 334.9 amu
