Which explanation BEST describes what happened to chocolate bar A? A. Heat was transferred to the chocolate bar by convection causing it to melt.
B.
Heat was transferred to the chocolate bar by radiation causing it to melt.
C
Heat was transferred to the chocolate bar by condensation causing it to meit
D.
Heat was transferred to the chocolate bar by evaporation causing it to melt.

Agas mixture with a total pressure of 745 mmhg contains each of the following gases at the indicated partial pressures: co2, 245 mmhg ; ar, 119 mmhg ; and o2, 163 mmhg . the mixture also contains helium gas. part a what is the partial pressure of the helium gas? phe p h e = nothing mmhg request answer part b what mass of helium gas is present in a 10.2-l sample of this mixture at 283 k ? m m = nothing g request answer

During chemistry class, carl performed several lab tests on two white solids. the results of three tests are seen in the data table. based on this data, carl has concluded that substance b must have bonds.

Reaction rate depends on how many molecules are coming into contact with each other with enough energy to react. increasing the temperature of the reactants will increase -