# science

posted by
**michelle**
.

what is the kinetic energy, in J, of

a)an Ar atom moving w/ a speed of 650m/s

b)a mole of Ar atoms moving w/ a speed of 650m/s?

a) K.E. = (1/2) M V^2

For M, use the mass of an Argon atom. It equals 0.040 kg (40 g) divided by Avogadro's number. M must be in kg to get the K.E. in Joules

b) Multiply the (a) result by Avogadro's number.

thanx