<u>Answer:</u> The additional information that is helpful in calculating the mole percent of XCl(s) and ZCl(s) is the molar masses of Z and X
<u>Explanation:</u>
To calculate the mole percent of a substance, we use the equation:

Mass percent means that the mass of a substance is present in 100 grams of mixture
To calculate the number of moles, we use the equation:

We require the molar masses of Z and X to calculate the mole percent of Z and X respectively
Hence, the additional information that is helpful in calculating the mole percent of XCl(s) and ZCl(s) is the molar masses of Z and X
Answer:
The energy of the particles increase and the molecules move more quickly.
Explanation:
The molecules are moving from a solid (barely moves, molecules close together) to a liquid (molecules slide past each other and take any shape), so molecules are moving more and have more energy
The quality or state of being volcanic.
# moles = mass (g) / Mr (relative atomic mass)
# moles = 458 / ((23*2)+32+(16*4)
# moles= 458 / 142 = 3.2253521126760...
= 3.23 moles
Mass of Sulphur dioxide : 256 g
<h3>Further explanation</h3>
Given
Reaction
S + O2 --> SO2 *
Required
Mass of Sulphur dioxide
Solution
mol of Sulphur (Ar=32 g/mol) :
mol = mass : Ar
mol = 128 : 32
mol = 4
From the equation, mol ratio S : SO2 = 1 : 1, so mol SO2 = 4
Mass of SO2 :
mass = mol x MW SO2
mass = 4 x 64
mass = 256 g