Sally's teacher tells her to find the masses of a sugar cube and a glass of water. sally finds the masses to be 10 g for the sugar cube and 100 g for the glass of water. then, the teacher tells her to put the sugar cube into the water. sally puts the cube into the glass of water and watches as it dissolves. then, the teacher tells sally to estimate the new mass of the glass of sugar-water.
what should sally guess as the new mass of the glass of sugar-water?

Sally should guess that the glass of sugar-water will have a mass of 110 g since the masses from the glass of water (100 g) and the sugar cube (10 g) will combine. it will be 110

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