For the following systems at equilibrium C:D:CaCO3(s)PCl3(g)+Cl2(g)⇌⇌CaO(s)+ CO2(g)PCl5(g)ΔH=+178 kJ/molΔH=−88 kJ/molC:CaCO3(s)⇌CaO(s)+CO2(g)ΔH=+1 78 kJ/molD:PCl3(g)+Cl2(g)⇌PCl5(g)ΔH=−8 8 kJ/mol classify these changes by their effect.

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.)

Imagine one batch of soup (batch “a”) is made with 8.19 g/can of salt, according to the recipe, and a second batch of soup (batch “b”) is made with 8.32 g/can of salt. explain which batch would be more resistant to frost damage if it is shipped a great distance in winter and explain why.

What is a for cio3-, the chlorate ion?