ACS jeopardy

exam 1

100

the relationship between ²⁰Ne, ¹⁹F^-  and ²⁴Mg²⁺ is

Same number of electrons (same ionic electron config.

200

What is the wavelength of a photon with a energy of 6.51x10^-19 J

305 nm

300

Hydrogen has 1 proton and a mass number of 1. Deuterium has 1 proton and a mass number of 2. What is their relationship

Isotopes. (D has a neutron while H has none)

exam 2

100

A Mg²⁺ and a unknown ion combine to form the compound MgX. What ion could X possibly be?

oxide, sulfide, etc

200

Arrange Li,Na, Ne, and Ar in terms of increasing first ionization energy

Na<Li<Ar<Ne

300

What is the condensed electron configuration of Ge

[Ar]3d¹⁰4s²4p²

know how to write the regular electron config. too 

exam 3

100

What criteria makes a molecule polar and give examples

1. It must contain at least one polar bond (2 atoms with a large difference in electronegativity)

2. The molecule must be asymmetric so that the dipoles do not cancel out.

HF, H₂O, CHCl₃, CH₂Cl₂, CHCl₃, NH_{3, etc.} 

200

Balance the reaction of CaCl₂ + sodium phosphate -> Ca₃(PO₄)₃ + NaCl

3,2,1,6

Sodium phosphgate is Na₃PO₄

300

What is the molecular geometry of ICl₄^-

Square planar - AX₄E₂

(electron geometry if octahedral due 6 total electron groups)

exam 4

100

What is the energy change for a system that releases 100 kJ of heat and has 25 kJ of work done on it? 

-75 kJ

q is negative, w is positive

200

What volume of 0.100 M HCl is needed to neutralize 25.0 mL of 0.100 M Ba(OH)₂

50.0 mL

300

A 10.0 g sample of silver is heated 100 C adn then added to 20.0 g of water at 23 C in a insulated calorimeter. At thermal equilibrium, the temperature of the system was 25 C. What is the specific heat of silver?

specific heat of water = 4.184 J/gC

0.22 J/gC

use the relationship q_system=-q_surroundings or 

q_silver + q_water = 0

Ch. 12

100

As strength of intermolecular forces increases, heat of vaporization _____ and vapor pressure ____

Increases, decreases

200

what is meantby the normal boiling point of a substance

The boiling point at 1 atm

300

What is the density of Xe gas at STP

5.86 g/L

Use ideal gas law. Solve for moles/volume and then multiply both sides by the molar mass. Density equation for gases!