Chemical ionization source, the reagent gas is present in large excess compared to the analyte. Electrons entering the source with energy around 200-500 eV will preferentially ionize the reagent gas. Then, the ion/molecule reactions produces more stable reagent ions and the resultant collisions with other reagent gas molecules will create an ionization plasma. Positive and negative ions of the analyte are formed by reactions with this plasma. The following reactions are possible with methane as the reagent gas. If ammonia is the reagent gas, For isobutane as the reagent gas, Self chemical ionization is possible if the reagent ion is an ionized
Negative number "a" as follows: The justification for why the product of two negative numbers is a positive number can be observed in the analysis of complex numbers. The sign rules for division are the same as for multiplication. For example, and If dividend and divisor have the same sign, the result is always positive. Another method of dividing negative numbers is that if one of the numbers being divided is a negative, the answer will be negative. The negative version of a positive number is referred to as its negation. For example, is the negation of the positive number . The