They have same chemical properties
for example the elements of group VIII are called noble gases .They are unreactive, odorless and colorless.
Answer:
Its pH value increases.
Explanation:
pH is the measure of alkalinity or acidity of a compound.
pH = - log [H+]
and pH + pOH = 14
where pOH is the measure of basicity of a solution, given by -log[OH-]
As a solution gets more basic that is higher [OH-], the pH increases, and on the other hand, as the pH of a solution decreases by one pH unit, the concentration of H+ increases by ten times.
A law is statement about an observed concept. A theory involves the explanation of scientific concepts or principles. A hypothesis is the predicted explanation about some concepts that has to be tested in order to prove it to be right. An observation is the observing the results of a scientific experiment carried out to test an hypothesis.
Here the given statement 'A chemist mixes sodium with water and witnesses a violent reaction between the metal and water,' can be classified as an observation as it explains what the chemists observes as a result of his chemical experiment or test..