In DNA a purine base should only pair with a pyrimidine base. Give one reason why this would be the case.

Assuming complete dissociation of the solute, how many grams of kno3 must be added to 275 ml of water to produce a solution that freezes at -14.5 c? the freezing point for pure water is 0.0 c and k_f is equal to 1.86 c/m

Which of the following best describes technology a. something created for only scientists to use b.the method of thinking that scientists use. c.the application of engineering to create useful products. c. a scientific idea

Which best describes the activation energy of a chemical reaction? a. the combined energy of all the reactants b. the amount of energy required for a reaction to occur c. the difference in energy between products and reactants d. the potential energy stored in the bonds of reactants and products