Answer: 17) d. 
18. c. The empirical formula of a compound can be twice the molecular formula.
Explanation:
Molecular formula is the chemical formula which depicts the actual number of atoms of each element present in the compound.
Empirical formula is the simplest chemical formula which depicts the whole number of atoms of each element present in the compound.
To calculate the molecular formula, we need to find the valency which is multiplied by each element to get the molecular formula.
The equation used to calculate the valency is:

The empirical mass can be calculated from empirical formula and molar mass must be known.
17. Thus the empirical formula of
should be 
18. The molecular formula will either be same as empirical formula or is a whole number multiple of empirical formula. Thus the empirical formula of a compound can never be twice the molecular formula.
Given that the pancake mix can be used for the preparation of 10 pancakes. The other ingredients added to the pancake mix would be eggs, cheese, milk, salt and baking soda. If all of thee ingredients are added to the pan cake mix in required proportions, we can make 10 pan cakes. So, the theoretical yield will be 10 pancakes. But in real Sam was able to prepare only 8 pancakes. That means the number of pancakes produced was limited by the amount of other ingredients. So, the actual yield will be 8 pancakes.
Hence the correct answer B) Theoretical yield
Answer:
They experience the same pressure
Explanation:
To answer this question, we recall Pascal's, Law Pascal's law states that an increase in pressure at a point in a confined cylinder containing a fluid, there is also an equal increase at all other points in that cylinder.
According to Pascal's law the pressure if the pressure expereienced by the larger diameter piston increases, the pressure experienced by the smaller diameter piston also increases by the same amount
However considering that pressure = Force/area F1/A1 =F2/A2
thus where A1 = πD²÷4 and A2 = πD²÷ 16 we have
we have F1×4/πD² = F2×16/πD² or F1 = 4× F2
They experience the same pressure but the larger cylinder delivers four times the force transmitted from he outside to the smaller cylinder