Different isotopes of a particular element contain the same number of

How many moles is 14.5 cm^3 of platinum? the density of platinum is 21.45 g/cm^3.

What is the atomic number of an atom that has 6 protons

Acertain reaction has a activation energy of 54.0 kj/mol. as the temperature is increased from 22c to a higher temperature, the rate constant increases by a factor of 7.00. calculate the higher temperature. c (report only numerical answer)