Which of the following is a physical change?

A) burning a piece of paper

B) lighting a match

C) chopping a piece of wood

D) a rusting nail

What is a good high school level science experiment?

Ammonia reacts with diatomic oxygen to form nitric oxide and water vapor: 4nh3 + 5o2 → 4no + 6h2o when 40.0 g nh3 and 50.0 g o2 are allowed to react, which is the limiting reagent?

Explain and give an example sex-linked disorder

Rocks formed from particles deposited by wind and water

The rate constant for a second-order reaction is 0.54 m-1s-1. what is the half-life of this reaction if the initial concentration is 0.30 m?

Which microscope came out first

Which exerts greater pressure on the floor-standing flat-footed or standing on tiptoe? on tiptoe, because the force acts over less area on tiptoe, because the force acts over more area flat-footed, because the force acts over more area flat-footed,

1. Sara tells Michael she is 160 centimeters tall, while Michael says he is 60 inches tall. If there are 2.54 centimeters in an inch, who is taller

How do you tell if a compound is polar or non polar

What two ions are central to the arrhenius definitions of acids and bases?