Q Problem 17.41 6 of 27 Constants | Periodic Table How many milliliters of 8.50×102 MNaOH are required to titrate each of the following solutions to the equivalence point? Part A 45.0 mL of 9.50×102 MHNO3 V = mL Part B 35.0 mL of 8.50×102 MCH3COOH V = mL Request Answer Solution Ans. Part A: Moles of HNO3 in sample = Molarity x Volume of solution in liters = 9.50 x 10-2 M x 0.045 L = 0.004275 mol # Balanced reaction: HNO3(aq) + NaOH(aq) -----> NaCl(aq) + H2O(l) According to the stoichiometry of balanced reaction, 1 mol HNO3 is neutralized by 1 mol NaOH. So, Required moles of NaOH to reach endpoint = 0.004275 mol Now, Required volume of NaOH solution = Required moles of NaOH / Molarity = 0.004275 mol / (8.50 x 10-2 M) = 0.004275 mol / (8.50 x 10-2 mol / L) = 0.05029 L = 50.29 mL Part B: Moles of CH3COOH in sample = Molarity x Volume of solution in liters = 8.50 x 10-2 M x 0.035 L = 0.002975 mol # Balanced reaction: CH3COOH(aq) + NaOH(aq) -----> CH3COONa(aq) + H2O(l) According to the stoichiometry of balanced reaction, 1 mol CH3COOH is neutralized by 1 mol NaOH. So, Required moles of NaOH to reach endpoint = 0.002975 mol Now, Required volume of NaOH solution = Required moles of NaOH / Molarity = 0.002975 mol / (8.50 x 10-2 M) = 0.002975 mol / (8.50 x 10-2 mol / L) = 0.035 L = 35.0 mL.

1. Quartz and glass both have a SiO4unit cell structure. Why is glass amorphous and quartz
crystalline?
Solution
Answer:
It is mainly because of the cooling temperatures
A silica melt needs to cool slowly to form quartz crystals. This generally happens at high
temperatures and pressures, such as those provided by a magmatic chamber(Quartz)
on the other hand, when the same melt is left to cool off at surface pressure and temperature
conditions, it cools out so fast it doesn't have time to develop a crystalline structure and remains
in an amorphous state (a glass).
The above is the main reason for their being different although have the same constitutional unit
Thanks :)