Draw the curved arrow mechanism for the formation of an acetal from acidic methanol and pentan-2-one in the fewest steps. When given the choice, draw the arrows that lead to the resonance structures with full octets around each atom other than hydrogen. Do not show any inorganic byproducts or counterions. Reagents needed for each step are provided in the boxes.

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)

Which of the following statements about hybrid orbitals is or are true? choose all that apply. choose all that apply. under sp2 hybridization, the large lobes point to the vertices of an equilateral triangle. after an atom undergoes sp hybridization there is one unhybridized p orbital on the atom. the angle between the large lobes of sp3 hybrids is 109.5∘

What happens to the temperature of a substance when the average kinetic energy of its particles increases?