Solution:
Alizarin or 1,2-dihydroxyanthraquinone (also known as Mordant Red 11 and Turkey Red is an organic compound with formula C14 H8 O4 that has been used throughout history as a prominent red dye, principally for dyeing textile fabrics. Historically it was derived from the roots of plants of the madder genus. In 1869, it became the first natural pigment to be duplicated synthetically.Alizarin is the main ingredient for the manufacture of the madder lake pigments known to painters as Rose madder and Alizarin crimson. Alizarin in the most common usage of the term has a deep red colour, but the term is also part of the name for several related non-red dyes, such as Alizarine Cyanine Green and Alizarine Brilliant Blue.
905. The source of energy that causes the least global warming is
Solution:
Fossil fuels — coal, petroleum, and natural gas — are the primary culprit behind climate change. They contribute more than 80 percent of greenhouse gas emissions — and 98 percent of CO2 emissions alone. On the contrary, Geothermal energy is thermal energy generated and stored in the Earth. It is clean and sustainable.
906. Thermal electricity is generated by using which of these ?
Solution:
Traditional thermal power plants: also called combustion power plants, they operate with energy produced by a steam boiler fueled by coal, natural gas, heating oil, as well as by biomass. The steam activates a turbine which, in turn, drives an alternator to produce electricity.
Solution:
Nucleon is one of the particles that makes up the atomic nucleus. Each atomic nucleus consists of one or more nucleons, and each atom in turn consists of a cluster of nucleons surrounded by one or more electrons. There are two kinds of nucleon: the neutron and the proton. The mass number of a given atomic isotope is identical to its number of nucleons. Thus the term nucleon number may be used in place of the more common terms mass number or atomic mass number. Until the 1960s, nucleons were thought to be elementary particles, each of which would not then have been made up of smaller parts. Now they are known to be composite particles, made of three quarks bound together by the so-called strong interaction. The interaction between two or more nucleons is called inter-nucleon interactions or nuclear force, which is also ultimately caused by the strong interaction. (Before the discovery of quarks, the term “strong interaction” referred to just inter-nucleon interactions).
909. Which one of the following metals is used to galvanise iron ?