Which of these metals Mg, Fe, Pb and Cu will dissolve readily in dilute HCl?

Which of these metals Mg, Fe, Pb and Cu will dissolve readily in dilute HCl?

  1. All the metals
  2. Mg, Fe and Cu
  3. Mg, Fe and Pb
  4. Mg and Fe only ✓

Explanation

Vectors have both magnitude (size) and direction. Written as column vectors (3, 4) or with arrow notation. Scalars have only magnitude (regular numbers). Velocity is a vector; speed is scalar.

Addition: add corresponding components. (2, 3) + (4, 1) = (6, 4). Graphically, place vectors head-to-tail. Subtraction: add the negative. Scalar multiplication multiplies each component.

Magnitude: √(x² + y²). Direction: arctan(y/x). Applications: physics (force, velocity), navigation, computer graphics. Vectors describe quantities where direction matters.