Explain the mechanism of the cleaning action of soaps.
Cleansing action of soaps: The dirt present on clothes is organic in nature and insoluble in water. Therefore, it cannot be removed by only washing with water. When soap is dissolved in water, its hydrophobic ends attach themselves to the dirt and remove it from the cloth. Then, the molecules of soap arrange themselves in micelle formation and trap the dirt at the center of the cluster. These micelles remain suspended in the water. Hence, the dust particles are easily rinsed away by water.
Write notes on the following:
(a) Saturated and unsaturated hydrocarbons
(b) Corrosion
(c) Precipitation reaction
In the adjoining figure, $\triangle CAB$ is a right triangle, right angled at A and $AD \perp BC$. Prove that $\triangle ADB \sim \triangle CDA$. Further, if $BC = 10$ cm and $CD = 2$ cm, find the length of AD. 
सड़क सुरक्षा के प्रति जागरूकता हेतु ट्रैफिक पुलिस की ओर से जनहित में जारी एक आकर्षक विज्ञापन लगभग 100 शब्दों में तैयार कीजिए।
The following data shows the number of family members living in different bungalows of a locality:
| Number of Members | 0−2 | 2−4 | 4−6 | 6−8 | 8−10 | Total |
|---|---|---|---|---|---|---|
| Number of Bungalows | 10 | p | 60 | q | 5 | 120 |
If the median number of members is found to be 5, find the values of p and q.
The existence of a chemical element in one or more physical forms happening in the same physical state is called Allotropes or allotropy. Allotropes may show different physical or chemical states turning on the atom arrangement or the number of existent atoms. While carbon and sulfur is the common element presenting allotropy. Carbon can make further allotropes due to its five-membered valency.
Read More: Allotropes of Carbon
Carbon is part of a p-block element.
The crystalline form of carbon consists of allotropes like;