Chemistry

13 s and p – Block Elements55Quick Quiz1. Give reasons of the following(a) HI is stronger acid than HF.(b) Although H-bonding in HF is stronger than that in H2O, H2O has much higher boilingpoint.(c) The acidic character of hydrides of VIIA elements increases on descending the group.2. Illustrate the oxidising properties of halogens by giving example of two typical reactions.3. Arrange the halogens in the decreasing order of their oxidising power.4. Give reasons for the following;(a) Chlorine is a stronger oxidising agent than iodine.(b) Halogens are the best oxidising agents.(c) Fluorine is a batter oxidising than chlorine.(d) Electronegativity of halogens decreases in the order F > Cl > Br > ISOCIETY, TECHNOLOGY AND SCIENCEFood and Beverage CanningAs early as 1940, can manufacturers began to explore adapting cans to packagecarbonated soft drinks. The can had to be strengthened to accommodate higher internal canpressures created by carbonation (especially during warm summer months), which meantincreasing the thickness of the metal used in the can ends. Otherwise, distortion of the endwould strain the seal, creating potential leaks or making cans unstackable for storage andtransport.Another concern for the new beverage can was its shelf life. Even small amounts ofdissolved tin or iron from the can could impair the drinking quality of both beer and soft drinks.Fortunately, beer, which is only mildly acidic, is relatively noncorrosive. In addition, beer agesnaturally, so it has a limited shelf life of about three months in any package. In contrast, thefood acids, including carbonic, citric and phosphoric, in soft drinks present a risk for rapidcorrosion of exposed tin and iron in the can. The consequences of off-flavors, color changesand leakage through the metal needed to be addressed. At this point, the can was upgradedby improving the organic coatings used to line the inside, making cans heavier and moreencasing. Elements/Metals – Their Mining and ExtractionDifferent elements/metals are not obtained such rather these are obtained after passingthrough different steps.