What type of reaction is shown below? Check all that apply. Ca 2H2O → Ca(OH)2 H2 synthesis decomposition combustion single replacement double replacement.

In the particles are arranged in a regular, repeating pattern. a)a crystalline liquid b)a crystalline solid c)all gases d)all solids

What element has similar physical and chemical properties as boron.

If you try to move a piano and are unable to move it, did you perform any work in the scientific sense of the word? yes? or no? this question is worth 20 points! let it be correct!