Suppose a student added naoh solution from the buret drop by drop until reaching the equilibrium point. instead of closing the stopcock, he mistakenly opened it wide but then immediately switched it off. check all the possible effects. too much naoh will flow into the flask. the solution will turn from pink to blue. the moles of naoh will be greater than needed. the computed hcl concentration will be greater than in actuality.

a,c,d

a,c,d

same for the second one

Explanation:

edge 2021

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g

conduction is the transfer of thermal energy (heat in transfer) due to collisions between the molecules in the object. collisions between adjacent atoms and molecules transfer kinetic energy from the warmer to the cooler object. the objects must be in physical contact.