25.00 ml of 0.500 M Na2CO3 at 20.00 ℃ is mixed with 29.00 ml of 0.600 M HCl, in a coffee-cup calorimeter at 20.00 ℃. After stirring and allowing the reaction to go to completion, the final temperature is 26.50 ℃. As the gaseous CO2 forms from the reaction under constant atmospheric pressure of 0.988 atm, the volume changes by 2.6 L per 1 mol of CO2. Assume the final solution has the density of 0.982 g mL and specific heat capacity of 4.184 J g • ℃ . Calculate the change in internal energy ΔE, of the reaction (in kJ mol).

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

56 moles of   lieter in chemistry

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

hope this : )