Which sample contains more atoms: 3.89 g of nickel or 6.61 g of silver? defend your answer

Nickel contains more atoms.

Explanation:

Number of atoms is determined by the Avogadro number.

1 mole of substance contains 6.022 X 10²³ atoms.

Given:

Mass of Nickel, Ni = 3.89g

Molecular weight of Ni = 58.6934g

Number of moles of Ni = 3.89/58.6934g

Number of atoms of Ni =

Number of atoms of Ni = 0.39 X 10²³

Mass of silver, Ag = 6.61g

Molecular weight of Ag = 107.8682g

Number of moles of Ag = 6.61/107.8682

Number of atoms of Ag =

Number of atoms of Ag = 0.36 X 10²³

Therefore, Nickel contains for atoms.

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.