Nursing Elites

1. Which type of bond involves the complete transfer of electrons between atoms?

• A. Covalent bond
• B. Ionic bond
• C. Metallic bond
• D. Hydrogen bond

Correct answer: B

Rationale: The correct answer is B, Ionic bond. Ionic bond involves the complete transfer of electrons from one atom to another, resulting in the formation of cations and anions. This transfer leads to the creation of strong electrostatic attraction between the oppositely charged ions. Covalent bonds, on the other hand, involve the sharing of electrons between atoms to achieve stability. Metallic bonds are formed in metals, where a sea of delocalized electrons surrounds positively charged metal ions, contributing to the metal's properties. Hydrogen bonds are intermolecular forces that occur between a hydrogen atom and a highly electronegative atom like oxygen or nitrogen, not involving the complete transfer of electrons.

2. The shimmering image of water seen on a hot road is a well-known example of:

• A. Reflection
• B. Refraction
• C. Interference
• D. Polarization

Correct answer: B

Rationale: The shimmering image of water seen on a hot road is a result of refraction, not reflection. Refraction is the bending of light as it passes from one medium to another of different optical density. In this case, the hot air just above the road has a different density than the cooler air above it, causing light to bend and create the illusion of water on the road. Refraction is the most suitable explanation for this phenomenon, as it involves the bending of light rays due to the change in the medium's optical density, producing the visual effect observed on the hot road. Reflection, interference, and polarization do not involve the bending of light due to changes in optical density and are not applicable to the scenario described on the hot road.

3. Which of the following statements is NOT true of most metals?

• A. Most of them are good conductors of heat.
• B. Most of them are gases at room temperature.
• C. Most of them are ductile.
• D. They make up the majority of elements on the periodic table.

Correct answer: B

Rationale: The correct answer is B because most metals are not gases at room temperature; they are usually solid and good conductors of heat. Metals are generally known for being good conductors of heat, ductile, and making up the majority of elements on the periodic table. Choice A is correct as metals, in general, are good conductors of heat. Choice C is also correct as most metals exhibit ductility. Choice D is correct as metals constitute the majority of elements found on the periodic table.

4. Two objects with equal masses collide head-on, both initially moving at the same speed. After the collision, they stick together. What is their final velocity?

• A. Zero
• B. Half their initial velocity
• C. Their initial velocity
• D. Twice their initial velocity

Correct answer: C

Rationale: In an inelastic collision where two objects stick together after colliding, momentum is conserved. Since the two objects have equal masses and equal initial velocities but opposite directions, their momenta cancel out. Therefore, after the collision, the combined mass will move at the same speed as the initial velocity, but in the direction of one of the objects. Choice A ('Zero') is incorrect because momentum is conserved, and the objects must move after the collision. Choice B ('Half their initial velocity') is incorrect as the final velocity is the same as the initial velocity due to momentum conservation. Choice D ('Twice their initial velocity') is incorrect as the final velocity cannot be twice the initial velocity based on the conservation of momentum principle.

5. In a neutral atom, the number of electrons is:

• A. Must be equal to the number of protons.
• B. Must be less than the number of protons.
• C. Must be greater than the number of neutrons.
• D. Can vary depending on the atom's temperature.

Correct answer: A

Rationale: In a neutral atom, the number of electrons must be equal to the number of protons to maintain electrical neutrality. Electrons carry a negative charge while protons carry a positive charge. By having an equal number of electrons and protons, the positive and negative charges balance each other out, resulting in an electrically neutral atom. Choice B is incorrect because in a neutral atom, the number of electrons and protons must be equal. Choice C is incorrect as it compares electrons to neutrons, which are not directly related in determining an atom's charge. Choice D is incorrect as the number of electrons in a neutral atom is not dependent on the atom's temperature but rather on the atom's balance of positive and negative charges.

Similar Questions