1. suppose 0.7542 g of magnesium reacts with excess oxygen to form magnesium oxide as the only product, what would be the theoretical yield of the product?

2. if 0.8922 g of magnesium oxide is obtained from the reaction indicated in #1 above, what would be the percent yield of the magnesium oxide?

3. suppose the percent yield was calculated to be over 100%, what possible reasons could you give to account for it?

Answer :

(1) The theoretical yield of product, is, 1.257 grams.

(2) The percent yield of is, 64.13 %

(3) If the percent yield is calculated to be over 100% then there might be some impurity present in the desired product.

Solution : Given,

Mass of Mg = 0.7542 g

Molar mass of Mg = 24 g/mole

Molar mass of MgO = 40 g/mole

First we have to calculate the moles of Mg.

Now we have to calculate the moles of

The balanced chemical reaction is,

From the reaction, we conclude that

As, 2 mole of react to give 2 mole of

So, 0.03142 moles of react to give 0.03142 moles of

Now we have to calculate the mass of

Theoretical yield of = 1.257 g

Experimental yield of = 0.8922 g

Now we have to calculate the percent yield of

Therefore, the percent yield of is, 70.97 %

If the percent yield is calculated to be over 100% then the product would be greater than 1.257 g which indicates that there might be some impurity present in the desired product.

if the temperature drops and becomes cool

then the atmosphere can be freezing as the water vapor in the air is at maximum (100%) and can be severely cold

also can be snowing lightly as the moisture in the air will start to solidify

and btw this is not chemistry but