Which of the following solutions can act as a buffer:. (a) KCN/HCN,
(b) Na2SO4/NaHSO4,
(c) NH3/NH4NO3,
(d) NaI/HI

Which term best describes the form sound takes as it travels away from a drum (a- gas)(b-music) ( c-waves) (d-particles

Compare and contrast solutions and suspensions

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.