Meaning: 1  improvise. 2  act without preparation. 3  to let things go as they may. 4  determined on the circumstances. 5  according to the demand of the situation.
Henry Moseley. English physicist Henry Moseley, who arranged the Periodic Table in order of the atomic numbers of the elements. Henry Moseley's research career lasted only forty months before tragically ending with his death on a Gallipoli battlefield in World War I. But in his classic study of the x-ray spectra of elements, he established the truly scientific basis of the Periodic Table by arranging chemical elements in the order of their atomic numbers. Henry Gwyn Jeffreys Moseley, who was always called Harry by his family, was born in Weymouth, England, on November 23, 1887.
Law of Conservation of Matter (Antoine Lavoisier). The first breakthrough in the study of chemical reactions resulted from the work of the French chemist Antoine Lavoisier between 1772 and 1794.Lavoisier found that mass is conserved in a chemical reaction.The total mass of the products of a chemical reaction is always the same as the total mass of the starting materials consumed in the reaction.he total mass of the products of a reaction therefore must be the same as the total mass of the reactants. Origins of Stoichiometry (Antoine Lavoisier). In his famous textbook, Trait lmentaire de Chimie, which was published in 1789, Lavoisier reported that water was roughly 85% oxygen and 15% hydrogen by weight.