PLEASE HELP ME!! Starting with 15.0 g of water at 45.0°C, how much heat is needed to raise it to the boiling point and then completely
convert to water vapor at 100 °C? (Hint: There is both a phase change and a temperature changel)
(Triangle)Hrusion = 6.01 kJ/mol
(Triangle)Hvap = 40.67 kJ/mol
a)3.45 kJ
b)8.45 kJ
c)37.3 kJ
d)5.00 kj
e)33.9 kJ

Determine the wavelength of the light absorbed when an electron in a hydrogen atom makes a transition from an orbital in the n=3 level to an orbital in the n=7 level.

Base your answer on the information below and on your knowledge of chemistry. nitrogen dioxide, no2, is a dark brown gas that is used to make nitric acid and to bleach flour. nitrogen dioxide has a boiling point of 294 k at 101.3 kpa. in a rigid cylinder with a movable piston, nitrogen dioxide can be in equilibrium with colorless dinitrogen tetroxide, n2o4. this equilibrium is represented by the equation below. 2no2(g) n2o4(g) + 58kj at standard pressure, compare the strength of intermolecular forces in no2(g) to the strength of intermolecular forces in n2(g).

What is the relation between concentration of reactants and the rate of chemical reaction?