Physical Science Final

What particle determines the identity of an element?

Proton

How do you find the number of neutrons in an atom?

Atomic mass − atomic number = neutrons

What is the charge of an ion with 11 protons and 12 electrons?

−1

Which group on the periodic table contains the most unreactive elements?

Noble gases (Group 18)

What type of ion forms when an atom gains electrons?

Anion

Write the formula for magnesium oxide using ions Mg²⁺ and O²⁻.

Mg

Define an exothermic reaction.

A reaction that releases heat

Balance the equation: Fe + O₂ → Fe₂O₃

4Fe + 3O₂ → 2Fe₂O₃

A car travels 60 km in 2 hours. What's its average speed?

30 km/h

State Newton's Second Law.

F = ma (Force = mass × acceleration)

What unit is force measured in?

Newtons (N)

A 10 N force pushes a 2 kg box. What's its acceleration?

5 m/s²

What form of energy is stored in a stretched spring?

Elastic potential energy

Which law states energy cannot be created or destroyed?

Law of Conservation of Energy

What's the formula for calculating thermal energy change?

Q = m × c × ΔT

Calculate the heat needed to raise 200 g of water by 5 °C (c = 4.18 J/g°C).

Q = 200 × 4.18 × 5 = 4,180 J

What's the symbol for wavelength?

λ (lambda)

What part of a wave is the highest point called?

Crest

Describe how sound travels through a solid

Faster than in liquids or gases due to tightly packed particles

If a wave is 3 m long and has a frequency of 2 Hz, what's its speed?

6 m/s

What happens to light when it enters water from air?

It slows down and bends (refraction)

Which color of visible light has the shortest wavelength?

Violet

Define total internal reflection.

When light hits the boundary at an angle greater than the critical angle and reflects entirely within the medium