Chemistry Exam 2 CHEM 1120 ECU

What is the sum of the coefficients "a + b + c +d", where a, b,c and d represent the coefficients of the balanced equation? a Mg3N2 (s) + b H2SO4 (aq) → c MgSO4 (aq) + d (NH4)2SO4 (aq)

9

Arrange the following element in order of increasing electronegativity Potassium, Silicon, Nitrogen

a) (Least electronegative) Potassium < Silicon < Nitrogen (Most electronegative)

When silver forms Ionic compounds, what charge does it normally assume?

1+

What is the approximate H-N-H bond angle in the molecule NH3?

109 degrees

Consider a double replacement, precipitation reaction involving AgNO3 (aq) and Na2CO3 (aq) to answer the next three questions? AgNO3 (aq) and Na2CO3 (aq) → ?? What is formed when Na2CO3 dissolves in water?

2 aqueous Na+ ions and 1 aqueous CO32- ions

What is the charge of the Ni atom in the ionic compound NiSO4 2-, 1- , 0, 1+, 2+

2+

Ionic Compounds are formed by a combination of what two types of elements?

A metallic and a nonmetallic

Consider a double replacement, precipitation reaction involving AgNO3 (aq) and Na2CO3 (aq) to answer the next three questions? AgNO3 (aq) and Na2CO3 (aq) → ?? 28. What two ionic compounds are expected from this double replacement reaction?

Ag2CO3 and NaNO3

What is the formula for an ionic compound that is formed by mixing Al3+ cations with CO3^2- AlCO3, Al2CO33, Al (CO3)3 , Al3(CO3)2, Al2(CO3)2

Al2(CO3)2

What is the systematic name of the compound with a formula Al2O3

Aluminum Oxide

Which Element From these atoms (N,F,C,Br,O) form compounds with other elements?

C (Carbon)

Consider the molecule, CF4. What can be stated about the polarity of the C-F bonds and the polarity of this molecule?

CF4 has polar C-F bonds and is a non-polar molecule

Which polyatomic ion listed below is acetate CH3COO1-, CrO4^2-, SO3^2-, OH1- , NH4^1-

CH3COO1-

A chemical property of Hydrogen, H2 is that it reacts with Oxygen, O2 to produce water, H2O (a molecular compound) as shown below. How does each element in the compound H2O attain the same number of electrons as their respective next nearest Noble gas? 2 H2 (g) + O2 (g) → 2 H2O (l)

Each hydrogen atom and the oxygen atom share two electrons.

Anions are formed when neutral atoms do what?

Gain Electrons

What is the correct systematic name for the compound Fe3(PO4)2 ?

Iron(II) phosphate

Given the table of electronegativity values below, which of the following bonds below would be considered polar covalent? Element Electronegativity Value Si 1.8 Ge 1.8 K 0.8 F 4.0

K-Si

Which of the following compound is potassium sulfite PS, K2SO3, KS, PSO3, K2SO4

K2SO3

Which of these compounds is considered an Ionic Compound PCl3, CBr4 , Mg3P2, NO2 , SF2

Mg3P2

Which of the following molecules is polar? The molecular geometry is indicated in parenthesis.

NH3 (Triagonal Pyramidial)

Which ion listed below obey the octet rule and are considered relatively stable when balanced with an ion of similar charge?

Na+1

Which of the following polyatomic ions have a (2-) charge associated with it? Cyanide, Sulfite, Nitrate, Hydronium, Hypochlorite

Sulfite

What is the systematic name for the compound with a formula of SCl2

Sulfur dichloride

What is the electron geometry for the molecule, PF3?

Tetrahedral

What is the molecular geometry for PF3

Trigonal Pyramidal

Consider the following redox reaction to answer the next two questions. Zn (s) + CuSO4 (aq) → ZnSO4 (aq) + Cu (s) What substance is getting oxidized in the reaction above?

Zn

What substance acts as the reducing agent in the reaction above? Zn (s) + CuSO4 (aq) → ZnSO4 (aq) + Cu

Zn

Consider the molecule, CO2. How many charge clouds (regions of electron density) surround the central carbon atom?

two