Chemistry mid-term units 5-6

The correct name for K2S is _____.

potassium sulfide

Electronegativity is a concept that is useful along with other concepts in

predicting the polarity of a bond

The correct name of the compound Na3N is _____.

sodium nitride

The correct name for SrO is _____.

strontium oxide

What is the molecular shape of CCl4?

tetrahedral

This shape puts bonding pairs at 120 degrees apart.

trigonal planar

VSEPR theory predicts that the geometry of the NH3 molecule is

trigonal pyramidal

What is the molecular shape of PCl3?

trigonal pyramidal

A covalent bond can occur between

two nonmetals

. The total number of nonbonding electron pairs present in the Lewis structure of CH4 is

0

Which of the following diatomic molecules is joined by a double covalent bond?

02

Which one of the following is the correct bond angle between atoms adopting a trigonal planar geometry?

120°

. The Lewis structure of PF3 shows that the central phosphorus atom has _____ nonbonding and _____ bonding electron pairs.

1; 3

When two atoms of fluorine bond, how many electrons will be shared between them?

2

When two atoms of nitrogen bond, how many pairs of electrons will be shared between them?

3

The charge on the manganese in the salt MnCl3 is _____.

3+

How many hydrogen atoms must bond to silicon to give it an octet of valence electrons?

4

sp3 hybridization involves the hybridization of how many atomic orbitals?

4

When calcium reacts with sulfur the compound formed is _____.

CaS

A molecule with a single covalent bond is _____.

Cl2

Which molecule is polar?

H2S

The only noble gas without eight valence electrons is _____.

He

Magnesium reacts with a certain element to form a compound with the general formula MgX. What would the most likely formula be for the compound formed between lithium and element X?

Li2X

When an atom of H and an atom of F bond together:

The F will be partially negative, because it has higher electronegativity than H

Which of the following elements can form diatomic molecules held together by triple covalent bonds?

nitrogen

Anions tend to be _____ and cations tend to be ______.

nonmetals; metals

Identify the compound that exhibits London dispersion forces.

CCl4

Predict the formula of the ionic compound that forms from calcium and fluorine.

CaF2

Predict the formula of the ionic compound that forms from magnesium and fluorine.

MgF2

. Predict the formula of the ionic compound that forms from magnesium and oxygen.

MgO

Which formula represents a nonpolar molecule?

N2

The Lewis structure of HCN shows that _____ has _____ nonbonding electron pairs.

N; 1

. Identify the compound that exhibits hydrogen bonding

NH3

Identify which compound dissolves in water.

NH3

What is the formula for sodium sulfate?

Na2SO4

Which of these elements does not exist as a diatomic molecule?

Ne

The formula for a salt is XBr. The X-ion in this salt has 36 electrons. The metal X is _____.

Rb

Element M reacts with fluorine to form an ionic compound with the formula MF3. The M-ion has 18 electrons. Element M is _____.

Scandium

How is molecular shape determined?

Shape is determined by the repulsion of the electron pairs in the bonded atoms.

What is the formula of the compound formed between strontium ions and nitrogen ions?

Sr3N2

Ammonia, NH3, adopts a tetrahedral geometry. However, the non-bonding pair on the central atom distorts the bond angle away from the expected 109.5˚. Which of the following statements correctly describes how the bond angle is distorted?

The actual bond angle is reduced; it is less than 109.5˚

VSEPR stands for what?

Valence-shell-electron-pair repulsion

The correct name for Al2O3 is _____.

aluminum oxide

The atoms in a molecule of water adopt what kind of geometry?

bent

The correct name for CaH2 is _____.

calcium hydride

A bond which comes to existence due to sharing of electrons is known as

covalent bonding

A bond which comes to existence due to transferring electrons is known as

ionic

This shape puts bonding pairs at 180 degrees apart.

linear

What is the molecular shape of all diatomic molecules?

linear

What is the molecular shape of carbon dioxide?

linear

Metals tend to _____ electrons and nonmetals tend to _____ electrons

lose; gain