Word count and just reall simple stuff u can just get the real version on the computer
Answer:
false
Explanation:
because elements never exist in nature as single isotopes they are always combined
Nothing happens because a physical change only changes the appearance of the substance, whereas a chemical change transforms the substance into something completely different.
i.e. (chemical change) wood + fire = ash
(physical change) wood + axe = smaller pieces of wood
212 ml of lead nitrate is required to prepare a dilute solution of 820.7 ml of lead nitrate.
Answer:
Option A.
Explanation:
Similar to Avagadro's law, there is another law termed as dilution law. As the product of volume and normality of the reactant is equal to the product of volume and normality of the product from the Avagadro's law. In dilution law, it will be as product of volume and concentration of the solute of the reactant is equal to the product of volume and concentration of solution.

So, as per the given question C1 = 5.45 M of lead nitrate and V1 has to be found. While C2 is 1.41 M of lead nitrate and V2 is 820.7 ml.
Then, 

So nearly 212 ml of lead nitrate is required to prepare a dilute solution of 820.7 ml of lead nitrate.