CHEM 103 Module 1 Exam Questions and Answers | Latest Update (Graded A+)

Classify each of the following as an element, compound, solution or heterogeneous mixture and explain your answer. 1. Barium chloride 2. Blood 3. Boron Answer: 1. Barium chloride - is not on periodic table (not element) - has two element names = Compound 2. Blood - is not on periodic table (not element) - no element names (not compound) appears to be one substance = Solution 3. Boron - is on periodic table = Element 7. Classify each of the following as a chemical change or a physical change 1. Fireworks exploding 2. Sweat evaporates from your skin 3. Fruit spoils Answer: 1. Fireworks exploding - explosion always = chemical change 2. Sweat evaporates from your skin - evaporate = physical change 3. Fruit spoils - formation of another substance, a change in odor, smell, etc = chemical change 8. Show the full Nuclear symbol including any + or - charge (n), the atomic number (y), the mass number (x) and the correct element symbol (Z) for each element for which the protons, neutrons and electrons are shown - symbol should appear as follows: xZy +/- n 35 protons, 44 neutrons, 36 electrons Answer: 35 rotons = Br35, 44 neutrons = 79Br35, 36 electrons = (+35 - 36 = -1) = 79Br35 -1 9.Name each of the following chemical compounds. Be sure to name all acids as acids (NOT for instance as binary compounds) 1. N2O4 2. SnO2 3. HClO4 Answer: 1. N2O4 - binary molecu