Download 科目名稱：普通化學 期中考(I) 日期：99年10月18日 學號 姓名 I. 名詞

科目名稱：普通化學
期中考(I)
學號
日期：99 年 10 月 18 日
姓名
I. 名詞解釋 (30%)
1.
2.
3.
4.
5.
Continuous spectrum and Line spectrum
Accuracy and Precision
Law of multiple proportions and Law of definite proportion
Covalent Bonds and Ionic Bonds
Extensive property and Intensive property
II. 填充題 (43%)
1. Perform the following mathematical operations and express the result to the
correct number of significant figures.
a.
b.
c.
1.285 × 10−2 + 1.24 × 10−3 + 1.879 × 10−1 =
(1.00866−1.00728)
6.02205×1023
=
6.6262×10−34 ×2.998×108
2.54×10−9
=
2. Which one has maximum significant figure in the following number
a) 0.0048, b) 0.00480, c) 4.80 × 10−2 , d) 4.8000 × 10−2
3. A light is emitted when an excited electron in the hydrogen atom falls from:
a. n = 5 to n = 2
b. n = 4 to n = 2
c. n = 3 to n = 2
Which transition results in the longest wavelength of light?
4. A photon has a frequency of 6.0 x 104 Hz. Convert this frequency into wavelength
(nm).
5. Give the maximum number of electrons in an atom that can have these quantum
numbers:
a. n = 0, l = 0, ml = 0
1
b.
n = 2, l = 1, ml = -1, ms = − 2
c.
n = 3, ms = +
d.
n = 1, l = 0, ml = 0
1
2
6. Fill the blanks in the following table (9%)
Symbol
84
38
Sr
24
12
Mg 2 
C 4
12
6
Protons
Neutrons
Electrons
1
科目名稱：普通化學
期中考(I)
學號
日期：99 年 10 月 18 日
姓名
7. Fill the blanks in the following table (14%)
Cation Anion Formula
Name
Ag2CO3
Potassium hypochlorite
Fe2+
ClKNO3
Sodium sulfite
III. 計算題 (35%)
1. Calculate the wavelength (in nm) of a photon emitted by a hydrogen atom when
its electron drops from the n = 5 state to the n = 3 state. (5%)
2. A cube made of platinum (Pt) has an edge length of 1.0 cm. (a) Calculate the
number of Pt atoms in the cube, (b) Atoms are spherical in shape. Therefore, the
Pt atoms in the cube cannot fill all of the available space. If only 74 percent of the
space inside the cube is taken up by Pt atoms, calculate the radius in picometers of
a Pt atom. The density of Pt is 21.45 g/cm3 and the mass of a single Pt atom is
3.240 × 10-22 g. [The volume of a sphere of radius r is (4/3)πr3.] 10%
3. A photon of ultraviolet light possesses enough energy to mutate a strand of human
DNA. What is the energy of a single UV photon and a mole of UV photons having
a wavelength of 25 nm? (10%)
4. Neutron diffraction is used in determining the structures of molecules.
(a) Calculate the de Broglie wavelength of a neutron moving at 1.00% of the
speed of light. (5%)
(b) Calculate the velocity of a neutron with a wavelength of 75 pm. (5%)
Useful information:
Na2SO4, KClO2, Na2S, KClO4, Na2SO3, KClO3, KClO, Na(NH4)2PO4, Na2(NH4)PO4,
Potassium nitrite, Silver carbonate, Potassium nitrate, Potassium nitride, Silver (I)
carbonate, Iron (II) chloride, Iron (III) chloride,
h: 6.626× 10−34 Js
c: 2.998× 108 m/s
RH: 2.18× 10−18 J
N: 6.022× 1023 1/mole
Electron: 9.11× 10−28 g
Proton: 1.67× 10−24 g
Neutron: 1.67× 10−24 g
2