Nursing Elites

1. Which of the following elements does not exist as a diatomic molecule?

• A. boron
• B. fluorine
• C. oxygen
• D. nitrogen

Correct answer: A

Rationale: The correct answer is 'boron.' Diatomic molecules consist of two atoms of the same element bonded together. Boron is an exception and does not exist naturally as a diatomic molecule. On the other hand, fluorine, oxygen, and nitrogen commonly exist as diatomic molecules in their natural states. Fluorine, for example, exists as F2, oxygen exists as O2, and nitrogen exists as N2.

2. What is the name of the device that separates gaseous ions by their mass-to-charge ratio?

• A. mass spectrometer
• B. interferometer
• C. magnetometer
• D. capacitance meter

Correct answer: A

Rationale: A mass spectrometer is a device specifically designed to separate gaseous ions based on their mass-to-charge ratio. This separation process involves ionization, acceleration of the sample, and the deflection of ions in a magnetic field according to their mass-to-charge ratio. The other options, 'interferometer,' 'magnetometer,' and 'capacitance meter,' do not perform the specific function of separating gaseous ions based on their mass-to-charge ratio, making them incorrect choices.

3. What is the name of the negatively charged subatomic particles?

• A. Protons
• B. Neutrons
• C. Electrons
• D. Isotopes

Correct answer: C

Rationale: The correct answer is C: Electrons. Electrons are the negatively charged subatomic particles. They are found outside the atomic nucleus and carry a negative charge. Protons are positively charged particles found in the nucleus, neutrons have no charge, and isotopes are atoms of the same element with different numbers of neutrons, not subatomic particles.

4. Which of these intermolecular forces might represent attraction between atoms of a noble gas?

• A. Dipole-dipole interaction
• B. London dispersion force
• C. Keesom interaction
• D. Hydrogen bonding

Correct answer: B

Rationale: Noble gases are non-polar molecules without a permanent dipole moment. The only intermolecular force applicable to noble gases is the London dispersion force, also known as Van der Waals forces. This force is a temporary attractive force resulting from the formation of temporary dipoles in non-polar molecules. Dipole-dipole interactions, Keesom interactions, and hydrogen bonding involve significant dipoles or hydrogen atoms bonded to electronegative atoms, which do not apply to noble gases.

5. What is the coefficient of O after the following equation is balanced?

• A. 1
• B. 2
• C. 3
• D. 4

Correct answer: A

Rationale: In a balanced chemical equation, the coefficient of oxygen (O) in O2 is already 2, so there is no need to adjust its coefficient further. Therefore, the coefficient of O remains as 1. Since the coefficient of O2 is 2, each O atom is represented by the coefficient of 1, and it does not change during the balancing process. Choices B, C, and D are incorrect as they suggest changing the coefficient of oxygen, which is not necessary for O2 in a balanced equation.

Similar Questions