Question

a sample of pure magnisium carbonate was found to contain 28.57% of magnisium 14.29% of calcium and 57.14% of oxygen .if law of constant composition is true what mass of magnisium ,carbon and oxygen should be present in 5g of magnisium carbonate

Answer 1

I hope that the statement of Law of Constant Proportion is known to you.

Now, by Law of Constant Proportion, the percentage of Each of the given elements(Mg, C and O) will be fixed in any given mass of MgCO3 (Magnesium Carbonate).

Now,

By Law of Constant Proportion, the masses of the element present in a given compound will be:

= [(Mass Percentage of Element)/100] × Given Mass of Compound

For Magnesium, it'll be
= [28.57/100]×5
= 1.42g

For Carbon, it'll be
= [14.29/100]×5
= 0.71g

For Oxygen, it'll be
= [57.14/100]×5
= 2.85g

To verify, we add them up, it gives
4.98g, which is approximately equal to 5g (the given mass of the compound), which verifies the law of constant proportion.

Answer 2

Answer:

Explanation:I hope that the statement of Law of Constant Proportion is known to you.

Now, by Law of Constant Proportion, the percentage of Each of the given elements(Mg, C and O) will be fixed in any given mass of MgCO3 (Magnesium Carbonate).

Now,

By Law of Constant Proportion, the masses of the element present in a given compound will be:

= [(Mass Percentage of Element)/100] × Given Mass of Compound

For Magnesium, it'll be

= [28.57/100]×5

= 1.42g

For Carbon, it'll be

= [14.29/100]×5

= 0.71g

For Oxygen, it'll be

= [57.14/100]×5

= 2.85g

To verify, we add them up, it gives

4.98g, which is approximately equal to 5g (the given mass of the compound), which verifies the law of constant proportion.