Answer:
The new findings support the theory that walking first arose underwater, preceding the move onto land and the development of toes and limbs adapted to land perambulation.
Answer:- 
Explanations:- The solution we have is a buffer solution and we know that a buffer solution resists a change in its pH if a strong acid or base is added to it.
Here, the buffer solution we have is of a weak base and it's conjugate acid. So, a strong acid(nitric acid) is added to this buffer then it reacts with the base present in the buffer so that the acid could be neutralized. This is called buffer action.
The net ionic equation is written as:
Note that 
is a strong acid and nitrate ion is the spectator ion so it is not included in the net ionic equation.
Answer: 39.948 grams
Explanation:
The SI base unit for amount of substance is the mole. 1 mole is equal to 1 moles Argon, or 39.948 grams
Answer:
1, just I) color.
Explanation:
Physical properties are the properties that can be observed without changing the composition of a substance, such as color, temperature, density, and boiling point.
A physical change is a change in the substance that only modifies its aggregation state, such as solidification, and boiling.
Chemical properties are the properties that need a reaction to being observed, such as the combustibility, which needs a combustion reaction to being quantified.
When a chemical reaction occurs, and the composition of the substance change, it's a chemical change.
So, the heating copper with carbon is a chemical reaction, and purification by electrolysis is too. Color is the only physical property.
Answer:
1 and 2
Explanation:
when we r adding chlorine to water
the water is clean
