Matters and Properties of Matters Exam 2 and Problem Solutions
Matters and Properties of Matters Exam 2 and Problem Solutions
1. Which one of the following statements is false for compounds?
I. Ratio of atoms in the compound is constant
II. Ratio of mass of elements in the compound
III. Compound has physical properties of elements, and does not have chemical properties of elements.
IV. Boiling and melting points of compounds are constant
V. They include at least two different atoms
Solution:
Compounds are pure matters that include at least two different atoms. Physical and chemical properties of compounds are totally different than its atoms. Thus, III is false for compounds.
2. Which one of the following matters are definitely mixture?
I. Liquid having same molecules but different atoms
II. Liquid having different molecules and same atoms
III. Liquid having same property in everywhere (homogeneous)
Solution:
I is pure compound. For example H2O contains same H2O molecules but different atoms like H and O.
II is mixture. For example O2+O3mixture contains different molecules but same atoms.
III is a definition of homogeneous liquid. It can be mixture or not. We can not say III is definitely mixture.
3. Using following explanations, classify X, Y and Z.
I. X can be decomposed into two matters having different properties y physical methods.
II. Y can not be decomposed into other matters by physical or chemical methods.
III. Z can only be decomposed by chemical methods into other matters.
Solution:
X is mixture
Y is element and
Z is compound
4. Which ones of the following name-compound pair is false?
I. Cu2O : Di copper monoxide
II. N2O3 : Nitrogen 3 oxide
III. Cl2O : Chlorine mono iodide
Solution: True names of compounds are given below:
I. Cu2O : Copper I oxide
II. N2O3 : Di nitrogen 3 oxide
III. Cl2O : Di chlorine mono iodide
5. Find name of following compounds.
I. CaSO3
II. N2O5
III. Al(NO3)3
IV. Cu(ClO4)2
Solution:
I. CaSO3 : Calcium sulphite
II. N2O5 : Di-nitrogen pentoxide
III. Al(NO3)3: Aluminum nitrate
IV. Cu(ClO4)2 : Copper II perchlorate
6. Melting and boiling points of X and Y are given below. So, find at which temperatures both of them are in liquid phase ;
60 0C, 35 0C or 10 0C.
Solution:
X is in liquid phase between temperatures 17 0C and 134 0C, Y is in liquid phase between temperatures -4 0C and 63 0C.
At 35 0C and 60 0C both of X and Y are in liquid phase. On the contrary, at 10 0C, X is in solid phase and Y is in liquid phase.