1. Laughing gas (nitrous oxide, N2O) is sometimes used as an anesthetic in dentistry. It is produced when ammonium nitrate is decomposed according to the reaction
NH4NO3(s) −→ N2O(g) + 2 H2O(ℓ).
How much NH4NO3 is required to produce
29.7 g of N2O?

2. Carborundum (SiC) is a hard substance made
by combining silicon dioxide with carbon (C)
as follows:
SiO2(s) + 3 C(s) −→ SiC(s) + 2 CO(g).
What mass of SiC is formed from the complete reaction of 1.43 mol of carbon?
Answer in units of g

the ozone layer acts as a filter for the shorter wavelength and highly hazardous ultraviolet radiation (uvr) from the sun, protecting life on earth from its potentially harmful effects. when the sky is clear, there is an inverse relationship between stratospheric ozone and solar uvr measured at the earth's surface.

a saline water is fed to a reverse osmosis unit at flow rate o rotameter connected to reject (retentate) line reads 8 installed in reject and permeate line reads 15.2 milli siemens/cm and 300 micro siemens/com respectively.