Ms. Pitt set up a classroom demonstration to show what happens when a sample of zinc metal is add a. ed to a flask containing hydrochloric acid (HCl). The diagram shows what the students in the classroom observed during the demonstration. The students made two other observations: The flask felt warmer after adding the sample. The sample became smaller over time. Which of the following is NOT an evidence of a chemical reaction in this example. A. Gas collected in the balloon
B. Temperature of sample is increased
c. Volume of HCl remains the same
D. Size of the zinc has become smaller

volume of HCl remains the same

Reaction

Zn (s) + 2HCl (aq)  ⇒  ZnCl₂ (s) + H₂ (g)

A. gas H₂ collected: true

B. Every chemical reaction produces or absorbs heat. In chemistry, this effect is described as the enthalpy of a reaction.

This reaction releases heat (exothermic) and causes the temperature to increase: true

C. the volume of HCl will decrease because it reacts: false

D. the size of the zinc metal decreases as it reacts: true

a rain shadow is a dry region of land on the side that is protected against the prevailing winds of a mountain range. the prevailing winds are the winds that occur most of the time in a particular place of the earth

prevailing winds carry air toward the mountain range. as the air rises up over a mountain range, the air cools, water vapor condenses, and clouds form. on this side of the mountains, called the windward side, precipitation falls in the form of  rain  or snow. this dry air produces a  rain shadow.

c, liquids evaporate, creating a gas