Calculate the amount of heat energy required to evaporate 25.7g of water at 100 degrees celcius. (molar heat of vaporization of liquid water= 4.07x10^4 j/mol)

5.82 ×10⁴ j

Explanation:

Given data:

Mass of water = 25.7 g

Amount of heat to evaporate it = ?

Molar heat of vaporization = 4.07×10⁴ j/mol

Solution:

First of all we will calculate the number of moles of water.

Number of moles = mass/ molar mass

Number of moles = 25.7 g/ 18 g/mol

Number of moles = 1.43 mol

Energy needed for one mole is 4.07×10⁴ j.

For 1.43 mol:

1.43 mol × 4.07×10⁴ j/ 1mol

5.82 ×10⁴ j

i'm assuming that the correct answer is indeed the first one/ "a"..

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.