honors chemistry final

Calculate the amount of heat (in kJ) required to raise the temperature of a 79.0 g sample of ethanol from 298.0 K to 385.0 K. The specific heat capacity of ethanol is 2.42 J/g°C

16.6 kJ

Choose the statement that is TRUE

Core electrons effectively shield outer electrons from nuclear charge

Consider the following reaction at equilibrium. What effect will increasing the temperature have on the system? Fe₃O₄(s) + CO(g) ⇌ 3FeO(s) + CO₂(g) H°=+35.9 kJ

The reaction will shift to the right in the direction of products

Consider the following reaction at equilibrium. What effect will increasing the temperature have have on the system? C₃H₈(g) + 5O₂(g) ⇌ 3CO₂(g) + 4H₂O(l) H°=-2220 kJ

The reaction will shift to the right in the direction of reactants

Consider the following reaction at equilibrium. What effect will increasing the pressure of the reaction mixture have on the system? 2H₂S(g) + 3O₂(g) ⇌ 2H₂O(g) + 2SO₂(g)

The reaction will shift to the right in the direction of the products

Consider the following reaction and its equilibrium constant: I₂(g) + Br₂(g) ⇌ 2IBr(g) Keq=1.1 x 10² A reaction mixture contains 0.41 M I₂, 0.27 M Br₂, and 3.5 M IBr. Which of the following statements is true concerning this system.

The system is at equilibrium

Which of the following is true is ΔEsys= -95 J

The system is losing 95 J, while the surroundings are gaining 95 J

Give the ground state electron configuration for Se

[Ar]4s²3d¹⁰4p⁴

Draw the Lewis structure for BrF₅. What is the hybridization on the Br atom.

sp³d²

Given w=0, and endothermic reaction has the following

+ΔH and +ΔE

Give the number of valance for SeCl₄

34

Chose the reaction that illustrates ΔH°f for Ca(NO₃)₂

Ca(s) + N₂(g) + 3O₂(g)→ Ca(NO₃)₂(s)

Choose the compound below that should have the highest melting point according to the ionic bonding model

CaF

Which of the following reactions is associated with the lattice energy of CaS (ΔH°latt)

Ca⁺²(g) + S⁻²(g) → CaS(s)

Place the following in order of increasing X-Se-X bond angle, where X represents the outer atoms in each molecule

SeCl₆ < SeF₂ < SeO₂ 90° 105° 120°

Using periodic trends, place the following bonds in order of decreasing ionic character; Si-F S-F P-F -4 -2 -3

Si-F, P-F, S-F

Which is true of an endothermic reaction? Circle the correct response.

Strong bonds break and weak bonds form.

Consider the following reaction at equilibrium. What effect will adding more H₂S have on the system? 2H₂S(g) + 3O₂(g)⇌ 2H₂O(g) + SO₂(g)

The reaction will shift in the direction of products

Consider the following reaction at equilibrium. What effect will adding more SO₃ have on the system? SO₂(g) + NO₂(g) ⇌ SO₃(g) + NO(g)

The reaction will shift in the direction of reactants

Consider the following equation at equilibrium. What effect will reducing the pressure of the mixture have on the system? Xe(g) + 2F₂(g) ⇌ XeF₄(g)

The reaction will shift to the left in the direction of reactants

Which of the following processes is endothermic

The vaporization of rubbing alcohol

If the system 2CO(g) + O₂(g) ⇌ 2CO₂(g) has come to equilibrium and then more CO(g) is added

[CO₂] increases and [O₂] decreases

Give the ground state electron configuration for Pb

[Xe]6s²4f¹⁴5d¹⁰6p²

Which of the following statements is TRUE

a ionic bond is formed through the transfer of electrons from one atom to another

A molecule containing a central atom with sp³ hybridization has a _______ electron geometry

tetrahedral

A molecule containing a central atom with sp³d hybridization has a _______ electron geometry

trigonal bipyramidal

Place the following in order of increasing electronegativity; Se S Cl

Se, S, Cl.

system gains thermal energy from surroundings

+q

work done on the system by the surroundings

+w

consider the molecule above. determine the hybridization of each of the 3 carbons labeled in figure 1.

1=sp²,2=sp³,3=sp³

determine the molecualr geometry at each of the 3 labeled atoms in figure 1.

1=trigonal planar, 2=tetrahedral, 3=trigonal pyramidal

How many of the following are diamagnetic; Cs Zr⁺² Al⁺³ Hg⁺²

2

The equilibrium constant is given for one of the reactions below. Determine the value of the missing equilibrium constant. H₂(g) Br₂(g) ⇌ 2HBr(g) K=3.8x10⁴ 2HBr(g) ⇌ H₂(g) + Br₂(g) K=?

2.6 x 10⁻⁵

Which of the following statements is TRUE

An orbital that penetrates into the region occupied by core electrons is less shielded from nuclear charge than an orbital that does not penetrate and therefore has a lower energy

Place the following in order of increasing IEI; N F As

As < N < F

How do coefficients from a chemical equilibrium appear when the chemical equilibrium expression is written

As exponents

Choose the compound below that should have the lowest melting point according to the ionic bonding model

BaCl₂

At equilibrium

Both the forward and reverse reactions continue

which of the following represents the lewis structure for Br⁻

Br ⁻

consider the molecule below. determine the hybridization at each of the 2 labeled carbons in figure 2.

C1= sp², C2=sp²

consider the molecule below. determine the molecular geometry at each 2 labled carbons in figure 2.

C1=trigonal planar, C2= trigonal planar

choose the best lewis structure for BeF₂

F -Be- F

Which of the following rules requires that each of the p orbitals at a particular energy level receive one electron before any of them can have two electrons

Hund's rule

Which of the following statements is FALSE?

K > 1 implies that the reaction is very fast at producing products

Place the following in order of decreasing metallic character; P As K

K > As > P

express the equilibrium constant for the following reaction. 2CH₃Cl(g)+Cl₂(g)⇌2CH₂Cl₂(g)+H₂(g)

K=

Express the equilibrium constant for the following reaction. 2 Na(s) + 2H₂O(l) ⇌ 2 NaOH(aq) + H₂(g)

K=[H₂][NaOH]²

Express the equilibrium constant for the following reaction. P₂(s) + 5O₂(g) ⇌ P₄O₁₀(s)

K=[O₂]⁻⁵

which of the following represent the lewis structure for Mg?

Mg

List the following in order of decreasing electronegativity difference; Cl₂ HCl NaCl 0 0.9 2.1

NaCl > HCl > Cl₂

Choose the paramagnetic species from below

Nb⁺³

Which reaction below represents the first ionization of O

O(g)→O⁺¹(g) + e⁻¹

Determine the electron geometry (eg) and molecular geometry (mg) of PF₅

eg= trigonal bipyramidal, mg= trigonal bipyramidal

Determine the electron geometry (eg) and molecular geometry (mg) of CO₃⁻²

eg= trigonal planar, mg= trigonal planar

Use the information provided to detmine ΔH°rxn for the following reaction; 3Fe₂O₃(s) + CO(g)→ 2Fe₃O₄(s) + CO₂(g) ΔHrxn=?

-47 kJ

system loses thermal energy to surroundings

-q

work done by the system on the surroundings

-w

For ΔEsys to always be -, what must be true

-w>+q

energy flows out of system into the surroundings

-ΔE

How many of the following molecules are polar; BrCl₃,Cs₂, SiF₄, SF₆

1

list the number of sigma bonds and pi bonds in a triple bond

1 sigma, 2 pi

Which of the following substances (with specific heat capacity provided) would show the greatest temperature change upon absorbing 100.0 J of heat

10.0 g Au, CAu= 0.128 J/g°C

Give the approximate bond angle for a molecule with a tetrahedral shape

109.5°

Give the approximate bond angle for a molecule with a trigonal planar shape

120°

According to the following reaction, how much energy is required to decompose 55.0 kg of Fe₃O₄? The molar mass of Fe₃0₄ is 231.55 g/mol

2.66x10⁵ kJ

How many of the following elements can form compounds with an expanded octet; Pb Kr Si B

3

How many of the following elements have 1 unpaired electron in the ground state; B Al S Cl

3

How many of the following have sp³d² hybridization on the central atom; SeCl₆, XeF₄,IF₅, AsCl₅

3

How many unpaired electrons are present in the ground state P atom?

3

The equilibrium constant is given for one of the reactions below. Determine the value of the missing equilibrium constant. N₂O₄(g) ⇌ 2NO₂(g) K=1.46 3N₂O₄(g) ⇌ 6NO₂(g) K=?

3.11

Determine the specific heat capacity of an alloy that requires 59.3 kJ to raise the temperature of 150.0 g alloy from 298 K to 398 K

3.95 J/g°C

Draw the Lewis structure for the molecule C₃H₄. How many sigma and pi bonds does it contain

6 sigma, 2 pi

Place the following in order of decreasing magnitude of lattice energy; KF MgS RbI

MgS > KF > RbI

What period 3 element having the following ionization energies (all in kJ/mol); IE1=1012 IE2=19 IE3=2910 IE4=4960 IE5=6270 IE6=22,200

P

Place the following elements in order of decreasing electronegativity; K Cs P

P, K, Cs.

No two electrons can have the same four quantum numbers is known as

Pauli exclusion principle

Place the following in order of increasing magnitude of lattice energy; Na₂ Rb₂O K₂O

Rb₂O < K₂O < Na₂O

A reaction in which products can react to re-form reactants is

Reversible

The Aufbau principle states that an electron

occupies the lowest available energy level

A molecule containing a central atom with sp³d² hybridization has a _______ electron geometry

octahedral

what orbital overlap is between the nitrogen and hydrogen in figure 1.

o⁻(sp³-s)

Energy that is associated with the position or composition of an object is called

potential energy

Which of the following signs on q and w represent a system that is doing work on the surroundings, as well as losing heat to the surroundings

q=-, w=-

Draw the Lewis structure for CO₂. What is the hybridization on the C atom

sp