Table of Contents: 1  INTRODUCTION, DEFINITION & VALUE OF RESEARCH. 2  SCIENTIFIC METHOD OF RESEARCH & ITS SPECIAL FEATURES. 3  CLASSIFICATION OF RESEARCH:Goals of Exploratory Research. 4  THEORY AND RESEARCH:Concepts, Propositions, Role of Theory. 5  CONCEPTS:Concepts are an Abstraction of Reality, Sources of Concepts.
Lead poisoning is a serious and sometimes fatal condition. It occurs when lead builds up in the body. Lead is a highly toxic metal and a very strong poison. It is found in lead-based paints, including paint on the walls of old houses and toys.
A sulfide formed with tin and antimony is called franckeite. Lead is found in the mineral nagyagite, a sulfide, along with gold, iron, antimony, and tellurium. Silver joins with lead and antimony in the sulfide andorite, AgPbSb3S6. Lead, copper and iron join in the sulfide betekhtinite. In the sulfide mineral hutchinsonite,(Tl, Pb)2As5S9 , lead joins with arsenic and thallium.