The nucleus is like theof the cell

If the atomic mass of an atom is 34 and the atom contains 13 protons, how many neutrons does the atom contain?

The vapor pressure of ethanol is 1.00 × 102 mmhg at 34.90°c. what is its vapor pressure at 61.61°c? (δhvap for ethanol is 39.3 kj/mol.)

How is the way a mixture is combined different from how a compound is combined?