The law of conservation of mass tells you that mass is neither created nor destroyed.
2Mg + O2 ==> 2MgO
50 g..+..x g...=......80
So what must x be?
2Mg + O2 ==> 2MgO
50 g..+..x g...=......80
So what must x be?
In this case, the reactant is magnesium (Mg) and the product is magnesium oxide (MgO). We are given that a piece of magnesium ribbon weighing 50g is burnt in air, resulting in the formation of 80g of magnesium oxide.
Using the law of conservation of mass, we can calculate the mass of oxygen:
Mass of magnesium + Mass of oxygen = Mass of magnesium oxide
Let's denote the mass of oxygen as "x."
50g (mass of magnesium) + x (mass of oxygen) = 80g (mass of magnesium oxide)
To find the value of "x," we can rearrange the equation:
x (mass of oxygen) = 80g (mass of magnesium oxide) - 50g (mass of magnesium)
Simplifying:
x = 30g
Therefore, the mass of oxygen combined with the magnesium in this reaction is 30g.