Answer:
0.156mol
Explanation:
Number of moles of a substance can be calculated from its mass by dividing its mass by molar mass i.e.
Number of moles (n) = mass/molar mass
Molar mass of PbCl4 is as follows, where Pb = 207.2g/mol, Cl = 35.5g/lol
PbCl4 = 207.2 + 35.5(4)
= 207.2 + 142
= 349.2g/mol
Using: mole = mass/molar mass
mole = 54.32 grams ÷ 349.2g/mol
mole = 0.1555
mole = 0.156mol
1. <span>The phase change in which a substance changes from a liquid to a gas is condensation. The correct option among all the options given is option "c".
2. </span>The phase change in which a substance changes from a solid to a liquid is melting. The correct option among all the options given is option "b".
3. The phase change in which a substance changes from a solid to a gas or vapor without changing to a liquid first is sublimation. The correct option is option "a".
In chemistry, the letter "H" represents the enthalpy of a system. Enthalpy refers to the sum of the internal energy of a system plus the product of the system's pressure and volume. The delta symbol is used to represent change. Therefore, delta H represents the change in enthalpy of a system in a reaction.
