Calculate the number of atoms in a 1.26×103 g sample of silicon.

2.71 x10^25 atoms Si

Explanation: Solution:

1.26x10²³ g Si x 1 mole Si / 28 g Si x 6.022x10²³ atoms Si / 1 mole Si

= 2.71 x10^ 25 atoms Si

question: ray weighs 100 kilograms, his wrestling partner, bobby, weighs 50 kilograms. if ray moves at 4 m s , how fast will bobby have to run at him to apply an equal amount of kinetic energy?

answer: 8 m/s he needs to run twice as fast to keep up so he has some work to do

explanation:   if the mass has units of kilograms and the velocity of meters per second, the kinetic energy has units of kilograms-meters squared per second squared.

question answered by

(jacemorris04)