Answer : If a substance is the limiting reactant, then it limits the formation of products because in the reaction it is present in limited amount.
Explanation :
While observing a chemical reaction, we can tell about whether a reactant is limiting or excess.
Step 1 : first write the chemical reaction and then balanced the chemical equation.
Step 2 : convert the given masses into the moles if mass of 
is 10.5 g and molar mass of is 28 g/mole and the mass of hydrogen is 0.40 g and molar mass of hydrogen is 2 g/mole.
Step 3 : Now we have to determine the limiting reagent and excess reagent.
Now we conclude that 
is the limiting reagent and hydrogen is an excess reagent.
Hypothesis :
Limiting reagent : It is the reagent in the chemical reaction that is totally consumed when the chemical reaction is complete. Limiting reagent limits the formation of products.
A material that allows heat/electricity to transfer is called a conductor.
First, recognize that this is an elimination reaction in which hydroxide must leave and a double bond must form in its place. It is likely an E2 reaction. Here is an efficient mechanism:
1) Pre-reaction: Protonate the -OH to make it a good leaving group, water. H2SO4 or any strong H+ donor works. The water is positively charged but still connected to the compound.
2) E2: Use a sterically hindered base, such as tert-butoxide (tButO-) to abstract the hydrogen from the secondary carbon. [You want a sterically hindered base because a strong, non-sterically hindered base could also abstract a hydrogen from one of the two methyl groups on the tertiary carbon, and that leads to unwanted products, which is not efficient]. As the proton of hydrogen is abstracted, water leaves at the same time, creating an intermediate tertiary carbocation, and the 2 electrons in the C-H bond immediately are used to make a double bond towards the partial positive charge.
In the products we see the major product and water, as expected. Even though you have an intermediate, remember that an E2 mechanism technically happens in one step after -OH protonation.
Compound is a pure substance where atoms of two or more elements are chemically bonded togather
