Some elements can exit in different Crystaline forms and are called allotropes, Which allotropic form of carbon is used as a dry lubricant in machines running at high temperature

Some elements can exit in different Crystaline forms and are called allotropes, What are the three important allotropic forms of carbon?

Some elements in p-block shows allotropy. What are the allotropic forms of sulphur?

P' block element consists of metals , non-metals and noble gases:- Which are the two allotropic forms of S that have S_8 units in the structure?

The allotropic form of carbon which is used for making lead of pencil is,(1)Lamp black (2)Charcoal (3)Graphite (4)Gascarbon

Monosaccharides containing an aldehyde group are called aldoses while those containing aketo group are called ketoses. The aldehyde group is always present at C_1 while the keto group is usually present at C_2 . All monosaccharides containing five and six carbon atoms have cyclic structures, furnaose (five membered) and pyranose (six membered). During ring formation, C_1 in aldoses and C_2 in ketoses becomes chiral and hence all these monosaccharides exist in two stereoisomeric forms called the alpha -anomer and the beta -anomer while C_1 and C_2 are called glycosidic or anomeric carbon atoms. In contrast, stereoisomers, which differ in configuration at any other chiral carbon other than the glycosidic carbon are called epimers. Two molecules of the same or different monosaccharides combine together through glycosidic linkage to form disaccharides. All monosaccharides (aldoses and ketoses) and most disaccharides reduce Tollens'reagent and Fehling's solution, undergo mutarotation and form osazones. Two forms of D-glucopyranose are called