You've experienced convection cooling if you've ever extended your hand out the window of a moving vehicle or into a flowing water stream. with the surface of your hand at a temperature of 30°c, determine the convection heat flux for (a) a vehicle speed of 40 km/h in air at -8°c with a convection coefficient of 40 w/m2. k and (b) a velocity of 0.2 m/s in a water stream at 10°c with a convection coefficient of 900 w/m2 k. which condition would feel colder? contrast these results with a heat flux of approximately 30 w/m2 under normal room conditions

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

the answer your looking for is c).