How can you tell a chemical change has happened?

What energy is it when you flip on a switch on a lamp

He table below gives the atomic mass and relative abundance values for the three isotopes of element m. relative abundance (%) atomic mass (amu) 78.99 23.9850 10.00 24.9858 11.01 25.9826 what is the average atomic mass (in amu) of element m? 2.86 5.36 24.30 24.98

Increasing the substrate concentration in an enzymatic reaction could overcome which of the following? a) the need for a coenzymeb) allosteric inhibitionc) competitive inhibitiond) insufficient cofactors