Based on Le Chatelier’s principle, what would be observed when the syringe is used to compress this gas mixture?

PART A MULTIPLE CHOICE (KNOWLEDGE – 3O)

Identify the letter of the choice that best completes the statement or answers the question.

Which of the following is the electron configuration for neon?

1s 2 2s 2 2p 4 3s 2 d. 1s 3 2s 3 2p 4

1s 1 2s 1 2p 6 3s 2 e. 1s 2 2s 2 2p 8

1s 2 2s 2 2p 6

Iron forms a common ion with a charge of +3. The electron configuration of this ion is:

1s 2 2s 2 2p 6 3s 2 3p 6 3d 5 d. 1s 2 2s 2 2p 6 3s 2 3p 6 3d 6

1s 2 2s 2 2p 6 3s 2 3p 6 3d 9 e. 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 3

1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 8

Which of the following is true of orbitals?

They are two-dimensional paths around the nucleus.

They can contain maximum of two electrons.

Their shapes are predicted by Bohr’s equation.

all of the above

none of the above

Which of the following is the electron configuration for the fluoride ion, F ─ ?

1s 2 2s 2 2p 4 d. 1s 2 2s 2 2p 6

1s 2 1p 6 e. 1s 2 2s 2 2p 6 3s 1

1s 2 2s 2 2p 5

In bonding orbital theory, a carbon-carbon triple bond consists of

3 pi bonds d. 1 sigma bonds + 4 pi bonds

1 sigma bond + 2 pi bonds e. 3 sigma bonds

2 sigma bond + 3 pi bonds

A substance is a brittle crystal that conducts electricity in molten liquid state only.

Which type of substance is it?

metallic crystal d. molecular crystal

ionic crystal e. frozen gas

covalent crystal

Four pairs of covalently-bonded electrons surrounding a central atom will be arranged

pyramidally d. linearly

spherically e. trigonally

tetrahedrally

The attractive forces that exist between atoms in liquid helium are known as

dipole-dipole forces d. hydrogen bonds

ion-dipole forces e. Van der Waals forces

covalent bonds

Which of these intermolecular forces exist in between water, H 2 O, molecules:

Van der Waals

metallic bonding

III. hydrogen bonding

covalent bonding

I only d. I, III and IV only

I and IV only e. I, II and III only

I and III only

The molar heat of vaporization of water is 42 kJ/mol. How much energy is released by the condensation of 3.0 g of water?

0.88 kJ d. 250 kJ

7.0 kJ e. 0.07 kJ

130 kJ

When solid ammonium chloride, NH 4 Cl, is added to water, the temperature of the solution decreases. Which statement best describes this observation?

The reaction is exothermic

Heat is released from the system, so it feels cooler.

NH 4 Cl (s) ! NH 4 Cl (aq) + 33.6 kJ

NH 4 Cl (s) ! NH 4 Cl (aq) “#$”%”&”()”*+”

NH 4 Cl (s) + H 2 O (l) ! NH 4 Cl (aq) “#,”%”-“”()”*+

The presence of a catalyst is thought to increase the rate of a reaction by

changing the products that are formed in the reaction

decreasing the enthalpy change of the reaction

increasing the enthalpy change of the reaction

decreasing the activation energy of the reaction

increasing the activation energy of the reaction

In a saturated solution of lead(II) chloride, the concentration of chloride ion is 6.2 x 10 -4 mol/L. The Ksp of lead(II) chloride would be which of the following?

1.9 x 10 -7 d. 2.3 x 10 -17

6.0 x 10 -11 e. none of the above

1.2 x 10 -10

The following diagram represents a kinetic energy distribution at two temperatures.

In comparing the two temperatures, it is obvious that