A20.0g sample of mercury(ii) oxide (hgo, m = 216.6) is heated strongly, causing it to decompose to metallic hg and o2 gas. what volume of o2 gas is produced( measured at stp)
(a) 1.03l (b) 2.07l (c) 4.14l (d) 14.0l
when 30.0 ml of 0.10 m agno3 is added to 30.0 ml of 0.10 m nacl, aqueous nano3 and solid agcl are formed. how much solid agcl is produced?
(a) 0.003 mol (b) 0.0060 (c) 0.030 mol (d) 0.060

Answer asap need by wednesday morning explain how a buffer works, using an ethanoic acid/sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.