Evaporation technique is used to separate a compound dissolved in a solvent by vaporizing the solvent and converting it to gaseous state. This leaves behind the solid residue present in the solution after the pure solvent is vaporized. The solvent vapors can be collected and condensed to get pure solvent. But the solid residue cannot be considered pure as it is the left over solid after all the solvent is evaporated. If the solution has some impurities, the solid left over includes all of the impurities. So, we cannot obtain a pure solid in evaporation technique.

The nucleus of an atom of the element is positively charged and atom has a hollow space inside it.
Explanation:
This experiment was conducted by Rutherford in this experiment. He placed a gold foil and surround it with a screen.
And He exposed gold foil in alpha particles rays in which he noticed that most rays passed through atom which conclude that atom has a large space, some rays get deflected and some reverse their path this show that the positive charge of nucleus of an atom.
Answer:
Explanation:
E = hc/λ
h = planck's constant = 6.66 x 10 ^ -34
c = speed of light = 2.98 *10^8 m/s
E = (6.66 x 10 ^ -34 )(2.98 *10^8)/32
= 19.85 * 10 ^-26
=0.62 x 10^-26
= 6.2 x 10^-27 J
Answer:
1:1.
Explanation:
From the equation we see that there is one mole of methane and one mole of carbon dioxide.