PAX PAX Chemistry and Physical Science 3

Question 1

What is the speed of light in a vacuum approximately equal to?

Accepted Answer

300,000 km/s

Answer

The speed of light in a vacuum is approximately 300,000 km/s (3 × 10⁸ m/s).

Question 2

Which of the following is an example of a mixture?

Accepted Answer

Saltwater solution

Answer

Saltwater is a homogeneous mixture where salt is dissolved in water; both components retain their chemical properties.

Question 3

What is the unit of electric current?

Accepted Answer

Ampere

Answer

The ampere (amp) is the SI unit of electric current, measuring the flow of electric charge.

Question 4

What type of energy does a moving object possess?

Accepted Answer

Kinetic energy

Answer

Kinetic energy is the energy an object has due to its motion; it depends on the object's mass and velocity.

Question 5

Which of the following has the lowest pH?

Accepted Answer

Orange juice (pH 3.5)

Answer

The lower the pH number, the more acidic the substance; orange juice at pH 3.5 is the most acidic option.

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