Knock out the false chemistry lines

Exercise and reference answers

Questions

1. Question

   Three of these lines about the modern periodic table are false.

   Choices

   1. Item

      Elements run in order of atomic number

      Correct

      Yes

   2. Explanation

      That is the older order Mendeleev used back in 1869.

      Item

      Elements run in order of atomic mass

   3. Explanation

      Group 18 holds the noble gases; the halogens are group 17.

      Item

      Group 18 holds the halogens

   4. Explanation

      Neon, helium and krypton are noble gases, but bromine is not.

      Item

      Bromine is one of the noble gases

2. Question

   Three of these lines about the elements are false.

   Choices

   1. Explanation

      Sodium melts near 98 degrees Celsius, which is low.

      Item

      Sodium has a very high melting point

   2. Item

      Iodine is the least reactive halogen

      Correct

      Yes

   3. Explanation

      Fluorine sits at the top of group 17 and reacts the most.

      Item

      Fluorine is the least reactive halogen

   4. Explanation

      Pure water is neutral, so its pH sits at 7.

      Item

      Pure water has a pH of 10

Instructions

Tap the three wrong lines in each set and leave the true one standing.

Explanation