Lithium standard solution (10,000 µg/mL Li in 2.0 mol/L HNO3) is used for calibration and quality control in analytical chemistry. It serves as a reference material for techniques such as Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Atomic Absorption Spectroscopy (AAS), and flame emission photometry to accurately determine lithium concentrations in environmental samples (e.g., water, soil), biological materials, food products, pharmaceuticals, and industrial materials. This solution ensures precise quantification in trace analysis, supporting research, regulatory compliance, and quality assurance in laboratories.