Aluminum is getting popular worldwide today as a ―Green Metal‖. Which among the following properties of Aluminum makes it a Green Metal?

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A. Aluminum has been providing a replacement of wood for saving forests and contributes in environment protection
B. Aluminum is a light metal and it is resistant to corrosion
C. Aluminum has fairly high rate of recycling and it can be re-used repeatedly without its quality deteriorating
D. The lands after the Bauxite mining can be restored very quickly and easily
✅ The correct answer is option C.

Now a days, a little pack of Silica Gel (granular beads of Silica made from Sodium Silicate) comes with many products to control humidity and avoid spoilage or degradation of some goods. Which among the following property of Silica gel makes it useful for that purpose?

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A. Silica gel molecules are hydrophilic with large surface area and so its molecules trap the moisture
B. Silica gel is a Hygroscopic substance with large surface area so its molecules absorb the moisture.
C. Silica gel molecules are with a portion that is charge-polarized and capable of hydrogen bonding, thus bonds with the water molecules
D. The semi permeable pouch in which silica gel is placed absorbs the moisture which later reacts with water.
✅ The correct answer is option B.