Calculate the ratio of H+ ions to OH– ions at a pH = 7. Find the concentration of H+ ions to OH– ions listed in Table B of your Student Guide. Then divide the H+ concentration by the OH– concentration. Record this calculated ratio in Table A of your Student Guide. Compare your approximated and calculated ratios of H+ ions to OH– ions at a pH = 7. Are they the same? Why or why not? Record your comparison in Table A. What is the concentration of H+ ions at a pH = 7? 0.0000001 mol/L What is the concentration of OH– ions at a pH = 7? mol/L What is the ratio of H+ ions to OH– ions at a pH = 7? :1

Clothing made of several thin layers of fabric with trapped air in between, often called ski clothing, is commonly used in cold climates because it is light, fashionable, and a very effective thermal insulator. so it is no surprise that such clothing has largely replaced thickand heavy old-fashioned coats. (a) consider a jacket made of five layers of 0.1-mm-thick synthetic fabric (k = 0.13 w/m·°c) with 1.5-mm-thick air space (k = 0.026 w/m·°c) between the layers. assuming the inner surface temperature of the jacket to be 28°c and the surface area to be 1.25 m2, determine the rate of heat loss through the jacket when the temperature of the outdoors is 0°c and the heat transfer coefficient at the outer surface is 25 w/m2·°c. (b) what would your response be if the jacket is made of a single layer of 0.5-mm-thick synthetic fabric? what should be the thickness of a wool fabric (k = 0.035 w/m·°c) if the person is to achieve the same level of thermal comfort wearing a thick wool coat instead of a five-layer ski jacket?