CHEM 199 EXAM 1

Which sketch represents an atom with the quantum numbers n=3, l=0, ml=0

• A

• B

• C

• D

When the electron in a hydrogen atom moves from n=6 to n=2, light with a wavelength

______ nm is emitted

The elements Y and Z are best described as:

• anions

• cations

• isotopes

• different elements

What is the frequency of light (in Hz) that has a wavelength of 1.23 x 10^-6 cm?

• 2.44 x 10^16

• 1.04 x 10^-13

• 9.62 x 10^12

• 3.69

• 4.10 x 10^-17

For which of the properties does Li have a larger value than potassium?

• ionization energy

• atomic radius

• molecular weight

• ionic radius

How many anions are there in 45.0 g of MgBr2?

• 2.94 × 10^22 anions

• 1.47 × 10^22 anions

• 2.94 × 10^23 anions

• 4.93 × 10^25 anions

The number of electrons and protons in 28.086 g of Si is what?

• 28

• 1.69 × 10^25

• 8.43 × 10^24

• None of the above

What is the symbol used to represent the factor 10^-9

• μ

• n

• G

• c

Silver has an atomic mass of 107.868 amu. The Ag-109 isotope (108.905 amu) is 48.16%. What is the amu of the other isotope?

• 109.905 amu
• 106.905 amu

• 105.868 amu
• 110.868 amu

Based on the indicated electronegativities, arrange the following in order of increasing ionic character: CsBr, LaBr3, PBr3, MgBr2

• PBr3, LaBr3, MgBr2, CsBr

• CsBr, LaBr3, MgBr2, PBr3

• CsBr, MgBr2, PBr3, LaBr3

• PBr3, MgBr2, LaBr3, CsBr

• Correct order is not given