If you have a 150-gram sample of cro3: • how many moles of cro3 do you have? • how many oxygen atoms do you have? • how many grams of oxygen do you have?

Answer :

(a) The moles of is, 1.5 moles.

(b) The number of oxygen atoms are,

(c) The mass of oxygen is, 72 grams.

Explanation : Given,

Mass of = 150 g

Molar mass of = 100 g/mole

Molar mass of oxygen = 16 g/mole

(a) First we have to calculate the moles of .

The moles of is, 1.5 moles.

(b) Now we have to calculate the number of oxygen atoms.

In , there are 1 atom of chromium and 3 atoms of oxygen.

According to the mole concept,

1 mole of contains number of oxygen atoms.

So, 1.5 mole of contains number of oxygen atoms.

The number of oxygen atoms are,

(c) Now we have to calculate the mass of oxygen.

As, 1 mole of contains 3 moles of oxygen

So, 1.5 mole of contains moles of oxygen

The mass of oxygen is, 72 grams.

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).