Ammonia is produced by the reaction of nitrogen and hydrogen: N2(g) + H2(g)  NH3(g) (a) Balance the chemical equation.
(b) Calculate the mass of ammonia produced when 35.0g of nitrogen reacts with hydrogen.

Which of the following is an indication that a substance has undergone a chemical change? a. no new product has been formed. b. the color of the substance has not changed. c. the original constitute has not changed. d. the molecular structure has changed.

While in europe, if you drive 125 km per day, how much money would you spend on gas in one week if gas costs 1.10 euros per liter and your car’s gas mileage is 32.0 mi/gal? assume that 1 euro=1.26 dollars

Ahelium balloon contains 16.9 l of helium at stp. how many atoms of helium are in the balloon