A11.0-m by 6.0-m by 3.0-m basement had a high radon content. on the day the basement was sealed off from its surroundings so that no exchange of air could take place, the partial pressure of22rn was 1.3 x 10-6 mmhg. calculate the number of112rn isotopes (12-3.8 days) at the beginning and end of 28 days. assume stp conditions. t-0 days: x 10rn atoms 1-28 days: x 10rn atoms

the leaf is an organ of a typical plant, and the main functions are to complete photosynthesis and allow the plant to exchange gas, just like how we have the respiratory system. leaves have the stomata, which collects maintains co2 and o2 levels. this is necessary for cell metabolism. the leaf also collects sunlight using chloroplasts. succinctly, leaves own a pivotal role in sustaining plant life.

1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄

2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%

6.4 cm (max) - 25 cm (min)