True or false about atoms and molecules

Exercise and reference answers

Questions

1. Statement is true

   No

   Statement

   Mass is lost when a chemical reaction happens.

2. Statement is true

   Yes

   Statement

   Water always contains hydrogen and oxygen as 1 to 8.

3. Statement is true

   No

   Statement

   Dalton said atoms can be created in a reaction.

4. Statement is true

   Yes

   Statement

   Two oxygen atoms are held by a double bond.

5. Statement is true

   No

   Statement

   Definite proportions hold for mixtures too.

Instructions

Decide whether each statement is true or false.

Explanation