Which is an indication that a chemical change to a substance has occurred?

A.

It changes shape.

B.

New substances are formed.

C.

Energy is used or given off.

D.

both B and C

Which of the following statements is accurate? Question 2 options: A) The wavelength of both transverse and longitudinal waves is measured parallel to the direction of the travel of the wave.

Which of these electronic transitions in hydrogen is exothermic? question 11 options: a. from n=3 to n=2 b. from n=1 to n=3?

A boat in a race accelerates uniformly at 0.2 m/s² for 18 seconds to reach a final speed of 6 m/s. Work out the initial speed of the boat.

Indicar verdadero (V) o falso (F) con respecto al movimiento parabólico : la componente horizontal de la velocidad permanece constante. () la componente vertical de la velocidad puede ser nula en un instante.

Diffraction and interference demonstrate which concept? A) particle nature of light B) wave nature of light C) polarization of light D) refraction of light

If the volume of a container increases, then the pressure will: A. first increase and then decrease. B. increase. C. stay the same. D. decrease.

How does the theory of natural selection explain the diversity of life?

What law states that when matter undergoes a physical or chemical change, no atoms are created or destroyed?

Which statement would be a valid argument in favor of using nuclear power? There are few negative impacts from mining the fuel. Reactors are safe from natural disasters. There are little to no waste products from fission.

How would you convince somebody that the momentum of an isolated system is constant?