Chem. 10
Test 1
I. Answer briefly.
1. Identify the following as A) physical property B) chemical property C) physical
change or D) chemical change
_____evaporation
_____the rusting of iron
_____viscosity
_____Ca metal burning in air
_____decantation
2. Classify the following as A) pure substance or B) mixture
_____beer
_____sugar
_____carbon
_____air
_____sea water
3. Give the name or symbol as appropriate
_____mercury
_____Sb
_____Au
_____Radon
_____silver
4. Four ways of separating the components of mixtures from each other are A) filtration B) evaporation C) decantation D) distillation. Which of these may best be used for each of the following mixtures? (Use letters)
_____salt in water
_____SiO2 in water
_____alcohol in water
_____mud particles suspended in water
5. Below are listed some of the properties of the element sodium. Classify each of them as A) physical or B) chemical (Use letters)
____A grayish-white solid
____Forms sodium oxide when in contact with air
____Soft enough as to be cut with a knife
____Lighter than gold
____Reacts with cold water with explosive violence forming hydrogen gas
6. Write T if the statement is true; F if false.
___Each measured number has some uncertainty in it.
___There are 12 inches in 1 foot. Each of these numbers is exact.
___The number 0.008050 miles has 7 significant figures.
___To identify an element, we need only to know its mass number.
___There are 8 neutrons in an atom of carbon-14.
7. Classify the following elements as A)metal B) nonmetal or C) metalloid.
___phosphorus
___chlorine
___silicon
___lead
___calcium
8. In no more than 2 sentences each, state the briefly the most significant
contribution of each of the following to our knowledge of atomic structure.
John Dalton
J.J. Thomson
Ernest Rutherford
Dmitri Mendeleev
9. Write a brief comparison of the following:
organic vs. inorganic compounds
ionic vs. molecular compounds
a period vs. a family of elements
a main group of elements vs. transition -metal group of elements
II. Problems
Show the complete solution, with units to earn any kind of credit. Express the answer to the proper number of significant digits. Answers only, without the solution will not be graded.
and 2.71 dou = 3.00 lam. How many foc is equivalent to 10.00 lam?
lists the energy consumed as 200. kWh. Change this to a) J and b) to calories.
6. A graduated cylinder holds 30.5 mL of water. A solid weighing 22.861 g is
dropped in the water. If the water level rises to the 41.6 mL mark, what is
the density of the object in g/mL?