chem concepts ch 4

3, 2, 1

Correctly order the steps required to determine the shape of a molecule, starting with first step at the top: 1) Determine the shape of the molecule by examining the position of the bonding and nonbonding electron pairs with respect to each other 2) Arrange the outer electrons in pairs, ensuring that all atoms other than hydrogen obey the octet rule 3) Determine the number of outer electrons associated with each atom in the molecule

average

For any element, the atomic mass recorded on the periodic table is not a whole number since it is a(n) _________ of the masses of its naturally occurring isotpes

fossil

Fuels formed by natural processes such as the decomposition of prehistoric organisms are called _____ feuls

lose, gain, noble

In the formation of ionic compounds a metal will ______ electrons and a nonmetal will _______ electrons to form an ion with the same number of electrons as the nearest _______ gas.

N = 82.4%, 0.824 H = 17.6%, 0.176

Match each element in the compound NH3 to its correct mass ratio and mass percentage N H 82.4%, 0.824 17.6%, 0.176

Cl -1, Sr +2, S -2, Al +3

Match each element with the appropriate charge in its ionic form Cl Sr S Al +3 -2 -1 +2

cation - anion with fewer electrons than its neutral atom anion - an ion with more electrons than its neutral atom positive - the charge of an ion with fewer electrons than its neutral atom negative - the charge of an ion with more electrons than its neutral atom

Match: cation anion positive negative An ion with more electrons than its neutral atom An ion with fewer electrons than its neutral atom The charge of an ion with more electrons that its neutral atom The charge of an ion with fewer electrons than its neutral atom

109.5°

The bond angle for a tetrahedral molecule (such as CH4) is equal to _______°

carbon

The most abundant isotope of ______ is the internationally accepted standard for determining atomic mass.

6.02, Avogadro's

There are exactly _____ x10^23 atoms in a 12 g of carbon-12 (given to TWO places after the decimal) This number is called __________ number

cation, -ide

When naming an ionic compound, the _______ is always named first. To name the anion, the root of the nonmental name is added to the suffix ______.

petroleum, coal, natural gas

Which of the following are examples of fossil fuels? petroleum coal wood natural gas nuclear fuel

1 and 2

Which of the following options correctly relate the number of outer electron groups in a molecule to its observed shape? 1) a molecule with two bonding and two nonbonding electron pairs will be bent 2) a linear shape is observed for a molecule with two bonding electron groups and no lone pairs 3) A molecule with three bonding pairs and one lone pair will be trigonal planar.

3, 4

Which of the following statements correctly describe isotopes? 1) Isotopes are atoms of the same element with the same mass. 2) Isotopes have different numbers of protons. 3) Isotopes have different numbers of neutrons. 4) Each element's atomic mass is a weighted average of the masses of the elements' isotopes.

ecological footprint

an estimate of the biologically productive space necessary to support a particular standard of living

mole

one ________ of any substance contains Avogadro's number of particles.