How many moles of water, h2o, contain 2.0×1022 molecules of water? (see the hints for assistance in interpreting scientific notation.)
express the quantity in moles to two significant figures.

Answer : The number of moles of water is,

Solution : Given,

Number of water molecules =

As we know that 1 mole of water molecule contains number of water molecules.

As, number of water molecules present in 1 mole  of water molecule

So, number of water molecules present in mole  of water molecule

Therefore, the number of moles of water is,

pv=nrt

explanation:

answer: semi-infinite solid initially at a uniform temperature of 400 ◦c is cooled at its surface by convection. the cooling fluid at a constant temperature of 200 ◦c has a convective coefficient (ha) of 250 w/m2.k. the physical properties of the solid: k = 20 w/m.k and α = 4 * 10-5  m2/s. using δx = 0.04 m and δt = 10 s. write the finite difference equations describing the transient heat transfer of the first five δx and the temperature profile after 30 s.