Answer:
A long lever with the fulcrum as close as possible to the load
Explanation:
If F be the effort , W be the weight , L₁ be the distance of load from fulcrum and L₂ be the distance of effort from the fulcrum ,
Taking moment of force about the fulcrum , we have
W x L₁ = F x L₂
F = W x ( L₁ / L₂ )
F will be minimum when L₁ will be minimum .
Hence fulcrum should be as close as possible to the load.
The percent composition<span> gives you only the empirical formula.
</span><span>To get the molecular formula, you must either know the molecular mass or do an experiment to find it.</span>
I found these four statements for that question:
Each molecule contains four different elements.
Each molecule contains three atoms.
Each molecule contains seven different bonds.
Each molecule contains six oxygen atoms.
The last one is true. Each molecule contains six oxygen atoms.
The number to the right of O and of (NO3) ares subscripts.
The chemical formula uses subscripts to indicate the number of atoms.
The subscript 2 in (NO3)2 means that there are two NO3 radicals.
And the subscript 3 to the right of O means that each NO3 radical has three atoms of O.
Then, the number of atoms of O is 2 * 3 = 6.
So, the true statement is the last one: each molecule of Ba (NO3)2 has six atoms of O.
From that molecule you can also tell:
- Each molecule contains one atom of barium
- Each molecule contains two atoms of nitrogen
- Each molecule contains two NO3 radicals
You can make 10 because that is the most N2 you have. The first one that runs out limits further molecules to be made