An unknown substance has a volume of 2 cm and a mass of 38.6 grams what is the density

Density of the unknown substance,

Explanation:

It is given that,

Mass of the unknown substance, m = 38.6 g

Volume of the unknown substance,

We need to find the density of the unknown substance. The total mass per unit volume of a substance is called its density. Its formula is given by :

So, the density of the unknown substance is . Hence, this is the required solution.

n2(g) + 3h2-> 2nh3(g)   this is the balanced equation

note the mole ratio between n2, h2 and nh3.   it is 1 : 3 : 2   this will be important.

moles n2 present = 28.0 g n2 x 1 mole n2/28 g = 1 mole n2 present

moles h2 present = 25.0 g h2 x 1 mole h2/2 g = 12.5 moles h2 present

based on mole ratio, n2 is limiting in this situation because there is more than enough h2 but not enough n2.

moles nh3 that can be produced = 1 mole n2 x 2 moles nh3/mole n2 = 2 moles nh3 can be produced

grams of nh3 that can be produced = 2 moles nh3 x 17 g/mole = 34 grams of nh3 can be produced

note:   the key to this problem is recognizing that n2 is limiting, and therefore limits how much nh3 can be produced.

a compound is a molecule made of atoms from different elements.

a. by the combination of an unlimited number of elements