Molar mass of a molecule is the sum of the atomic mass of the individual elements in the molecule.
Atomic mass of Pb = 207 amu
Atomic mass of N = 14 amu
Atomic mass of O = 16 amu
Here amu stands for atomic mass unit
Molar mass of Pb(NO₃)₂ = 207 + [14 + (16 x 3)] x 2
= 207 + 28 + (48) x 2 = 331 g/mol
A. All matter is composed of tiny particles that can vary in shape, size, and weight.
B. Solid matter is composed of square-shaped particles and liquid matter is composed of flat particles.
C. Solid matter is composed of atoms and liquid matter is composed of elements.
(B) increases the fraction of reactant molecules with a given kinetic energy.
(C) provides an alternate path with a different activation energy.
(D) lowers the enthalpy change in the overall reaction