1 A physical change, such as a state change or dissolving, does not create a new substance, but a chemical change does. 2  In a chemical reaction, the atoms and molecules that interact with each other are called reactants. 3  In a chemical reaction, the atoms and molecules produced by the reaction are called products.
FidelityÂ® Defined Maturity Funds. Defined Maturity Funds (DMFs) are an innovative way to invest in municipal bonds. Like Fidelity's other municipal bond funds, DMFs offer professional management, diversification, and seek to provide federally tax-exempt monthly income. They can also be sold at the end of each business day at their net asset value.
Weighted Average Maturity - WAM. What is 'Weighted Average Maturity - WAM'. Weighted average maturity (WAM) is the weighted average amount of time until the maturities on mortgages in a mortgage-backed security (MBS). This term is used more broadly to describe maturities in a portfolio of debt securities, including corporate debt and municipal bonds.