University:
Campbell University
Course:
CHEM 111 | General Chemistry I
Academic year:

2024
Views:

181

Pages:

2
Author:

Barkaiwqi

KEY Atoms, Molecules and Ions Name - ___________________ 1.) Classify each of the following as an atom, molecule or ion. S2- ___ion___ O2 ___molecule___ Sb ___atom___ O ___atom___ Al3+ ___ion___ NH3 ___molecule___ 2.) A clear glass bottle contains white sand, some nails, salt water with some dye dissolved in it and a layer of gasoline on top. How many phases are present in this system excluding the bottle and lid? Answer – 6 phases (air on top) 3.) Classify each of the following as heterogeneous or homogeneous. Diamond ___homogeneous___ tree ___heterogeneous___ egg ___heterogeneous___ 4.) If you had 10 g of gold, should you refer to it as an atom or an element? Answer – element. There is only one type of atom, Au. 5.) In what way are a true solution and a compound similar? In what ways do they differ? Answer – Similar in that both are homogeneous (composed of one phase). They differ in that a compound is a pure substance and a solution is a mixture of two pure substances. 6.) Which of the following are the possible classifications (element, compound, true solution, or mechanical mixture) for the items listed below? There may be more than one answer for each example. a.) a clear liquid which can be boiled away to leave a white solid. ___solution___ b.) a collection of solid particles, some of which are white and some are red. __mechanical mixture__ c.) a solid which melts at 170oC. ___element, compound or solid solution___ d.) a gas. __element, compound or solution__ 1 KEY e.) a liquid. __element, compound or solution___ f.) a liquid which boils away completely at 136oC. When the liquid is strongly heated in a closed container, a yellow gas and solid are produced. __compound or solution__ 7.) Which of sugar, dirt and air are pure substances and which are mixtures? Answer – sugar = pure substance dirt = mixture air = mixture 8.) How many phases are present in a regular pencil? Answer – 5 wood, graphite, metal, eraser and paint (2 colors). 9.) Classify each of the following as a mixture or a compound. a.) alcohol (CH3CH2OH) __compound__ b.) soda pop __mixture__ c.) CH3OH in H2O __mixture__ d.) vinegar __compound__ e.) mini-wheats __mixture___ f.) pizza __mixture__ g.) baking soda ___compound___ h.) peanut butter cookies __mixture__ i.) popcorn with salt and butter __mixture__ j.) milk __mixture__ 2