What volume of a 2.10 M NaCl solution is needed for a reaction that requires 138 g of
NaCl?
Answer in units of L.

146.3g NaCl (mol NaCl/58.44g NaCl) = 2.50 mol NaCl

1.5M NaCl = 1.5 mol NaCl / 1 L = 2.5 mol NaCl / x L, solve for x

x L = 2.5 mol NaCl / 1.5 mol NaCl = 1.66 L

It gives the answer and all the working.

To put it another way:

Dividing the amount required by the molar mass

we quickly see that 2.5 moles are required.

One litre of 1.5 molar solution gives 1.5 moles

we need a further mole, which is 2/3 of 1.5 so 2/3 of a litre.

explanation:

i think option no d is the correct answer

a 20-cm-long, cylindrical graphite (pure carbon) rod is inserted into an oxidizing atmosphere at 1145 k and 1.013 x 105 pa pressure. the oxidizing process is limited by the diffu- sion of oxygen counterflow to the carbon monoxide that is formed on the cylindrical surface.