The balance chemical reaction is:
<span>6 Li(s) + N2(g) → 2 Li3N(s)
We use the amount of the Lithium reactant and the relations of the substances from the reaction to calculate the amount of product produced. We do as follows:
1.75 mol Li ( 2 mol Li3N / 6 mol Li ) (34.83 g / mol) = 20.32 g Li</span>
A chemical change is when a substances chemical properties change, for example, baking a cake. A physical change is when the appearance/odor/texture etc. change, for example, ice melting
<span>Even in space, there is still presence of gravity. The
cause of weightlessness is not how far above the earth the space shuttle is but
rather how fast it is travelling. The shuttle is in free fall causing
weightlessness, but it is travelling fast enough to miss the earth as it falls.
Similarly, the airplane could also provide weightlessness if it went free fall
as well. However, that ends as the plane hits the ground. </span>