Key Concepts: 1  Legumes (family Fabales) develop root nodules that harbour Rhizobium bacteria (rhizobia). 2  Endosymbiotic bacteria (bacteroids) convert nitrogen to ammonia (biological nitrogen fixation). 3  Legume crops restore fertility to agricultural soils by capturing nitrogen from the atmosphere.
To have gold in your possession itself is a satisfying feeling. It increases a person's self-worth. The person wearing gold displays increased self-confidence. It is pleasureful experience starting from buying a jewelry to wearing a jewelry till seeing it inside a decorative box. Gold has a special quality to make you feel happy and satisfied.
Pure gold is too soft to be used in everyday jewelry, so it is alloyed with other metals to make it stronger and more durable. Pure gold is 24 karat, and 14 karat gold refers to an alloy of gold that contains at least 58.3% pure gold by weight. The balance is made up of other metals to give it strength. Gold is often alloyed with copper, silver, and zinc. Copper is ductile and hard, but tends to tint the alloy pink and is prone to oxidizing.