Heat can travel from one place to another in three ways: Conduction, Convection and Radiation. Both conduction and convection require matter to transfer heat. If there is a temperature difference between two systems heat will always find a way to transfer from the higher to lower system.
Answer:
one in a 2s orbital
Explanation:
Because of the peak near the nucleus in the 2s curve there is a higher probability of finding a 2s within 4 Å of the nucleus. In a multi-electron atom an electron in a 2s orbital will have a lower energy than one in a 2p orbital
Answer: The new penny is not pure copper
Explanation:
Density 
is defined as a relation between the mass 
and the volume 
:
Now, we are told the density of pure copper is:
And we are given the mass and volume of the new penny, with which we can calculate its density:
As we can see the density of this penny is not equal to the density of pure copper, hence the new penny is not pure copper.
