Chem Quiz #5

This graph show temperature vs. energy data for a substance. What is the melting point of this substance?

• 0^o C

• 20^o C

• 50^o C

• 90^o C

How many neutrons are in an atom of Pu-246?

• 94

• 150

• 152

• 246

A teacher wants to demonstrate a chemical reaction to her students. Which activity would best demonstrate a chemical reaction?

• placing a metal in an acid to create a gas

• measuring the densities of liquid water and ice

• melting a solid piece of aluminum

• filling a balloon with helium gas

This chart shows the effects of several solutions on litmus paper. Which solutions are most likely acids?

• Solutions 1 and 3

• Solutions 2 and 5

• Solutions 3 and 6

• Solutions 4 and 7

This is an unbalanced equation representing a chemical reaction.

HgO --> Hg + O₂

Which equation is the correctly balanced chemical equation for this reaction?

• HgO --> Hg + 2O₂

• 2HgO --> Hg + O₂

• 2HgO --> 2Hg + O₂

• 2HgO --> Hg + 2O₂