Three substances A, B, and C melt at 0° C, 50° C, and -150° C respectively, and their boiling points are 100° C, 200° C, and 10° C . State the physical nature of A, B, and C at room temperature.

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.)

4. glenn andrews recently bought a motorcycle for $3,950. if he had to pay 6% sales tax on the bike, what was the total cost of the motorcycle?

La reaccion entre monoxido de nitrogeno (no) y oxigeno para formardioxido de nitrogeno (no2) es un paso determinante para la formacion del smog, la reaccion es la siguiente: 2no + o2 = 2no2 cual sera el numero de moles de no2 que se formaran por la reaccion completa de 8 moles de oxigeno con suficiente monoxido?