What number should be placed in front of NH3 to balance this chemical
equation?
___NH3 – N2 + 3H2

A. 3

B. 1

C. 4

D. 2

Calculate the temperature rise when 0.2g of propane is used to heat 400cm cubed of water.

There is a set up transformer that doubles the voltage. if the primary coil has a voltage of 10 v

What are the two most influential greenhouse gases in maintaining the earth's climate? a) carbon dioxide & silicon b) water vapor & carbon dioxide c) silicon & oxygen d) nitrogen & water vapor