Useful Equations and Conversions

Introduction

The adequate development of any analytical procedure depends on that, from its inception and planning to the preparation of the reagents, the choice of suitable laboratory instrument, material and products, as well as the final result and its interpretation. In this process, basic equations and conversions of analytical chemistry run through it, though it is less noticeable. Here, we systematically list the some useful equations and conversions of analytical chemistry.

Topic 1: Useful Equations

Useful Equations

Topic 2: Useful Conversions

Parts per Billion	Parts per Million	Parts per Thousand	Percent
	10000 ppm	10	1.0%
1000000 ppb	1000 ppm	1	0.1%
100000 ppb	100 ppm	0.1	0.01%
10000 ppb	10 ppm	0.01	0.001%
1000 ppb	1 ppm	0.001	0.0001%
100 ppb	0.1 ppm	0.0001	0.00001%
10 ppb	0.01 ppm	0.00001	0.000001%

parts per million (ppm) = micrograms/gram (µg/g) = micrograms/milliliter (µg/mL) = nanograms/milligram (ng/mg) = picograms/microgram (pg/µg) = 10^–6	parts per billion (ppb) = nanograms/gram (ng/g) = nanograms/milliliter (ng/mL) = picograms/milligram (pg/mg) = 10^–9
grams/milliliter (g/mL) = milligrams/microliter (mg/µL)	micrograms/milliliter (µg/mL) = nanograms/microliter (ng/µL)

Topic 3: Composition and Composition Conversions of Concentrated Reagent

Concentrated Reagent	Formula	Formula Weight	Approximate Strength (% w/w)	Assay Limits (% w/w)	Molarity (M)	Quantity To Prepare 1 L 1 M Solution (mL)	Normality (N)	Quantity To Prepare 1 L 1N Solution (mL)
Acetic acid	CH₃COOH	60.05	99.8	≥99.7	17.4	57.5	17.4	57.5
Formic acid	HCOOH	46.03	90.0	88.0–96.0	23.6	42.5	23.6	42.5
Hydrochloric acid	HCl	36.46	37.2	36.5–38.0	12.1	82.5	12.1	82.5
Hydrofluoric acid	HF	20.01	49.0	48.0–51.0	28.9	34.5	28.9	34.5
Nitric acid	HNO₃	63.01	70.0	68.0–70.0	15.9	63.0	15.9	63.0
Perchloric acid	HClO₄	100.46	70.5	69.0–72.0	11.7	85.5	11.7	85.5
Perchloric acid	HClO₄	100.46	61.3	60.0–62.0	9.5	105.5	9.5	105.5
Phosphoric acid	H₃PO₄	98.00	85.5	≥85.0	14.8	67.5	44.4	22.5
Sulfuric acid	H₂SO₄	98.08	96.0	95.0–98.0	18.0	55.5	36.0	28.0
Ammonium hydroxide	as NH₃	35.05	29.0	28.0–30.0	14.5	69.0	14.5	69.0
Potassium hydroxide	KOH	56.11	45.0	85.0	11.7	85.5	11.7	85.5
Sodium hydroxide	NaOH	40.00	50.5	>97.0	19.4	51.5	19.4	51.5