Aluminum oxide (used as an adsorbent or a catalyst for organic reactions) forms when aluminum reacts with oxygen. 4al(s) + 3o2(g) ® 2al2o3(s) [balanced] a mixture of 82.49 g of aluminum ( = 26.98 g/mol) and 117.65 g of oxygen ( = 32.00 g/mol) is allowed to react. what mass of aluminum oxide ( = 101.96 g/mol) can be formed?

Answer : The mass of aluminium oxide formed can be 155.8 grams.

Solution : Given,

Mass of Al = 82.49 g

Mass of = 117.65 g

Molar mass of Al = 26.98 g/mole

Molar mass of = 32.00 g/mole

Molar mass of = 101.96 g/mole

First we have to calculate the moles of Al and .

Now we have to calculate the limiting and excess reagent.

The balanced chemical reaction is,

From the balanced reaction we conclude that

As, 4 mole of react with 3 mole of

So, 3.057 moles of react with moles of

From this we conclude that, is an excess reagent because the given moles are greater than the required moles and is a limiting reagent and it limits the formation of product.

Now we have to calculate the moles of

From the reaction, we conclude that

As, 4 mole of react to give 2 mole of

So, 3.057 mole of react to give moles of

Now we have to calculate the mass of

Therefore, the mass of aluminium oxide formed can be 155.8 grams.

"hydrogen bonding is the attraction of h atoms in the water molecule (slight + charge) to o atoms in a neighboring water molecule (slight - charge); it is a weak interatomic force. but it is still strong enough to the water molecules "stick" together."