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.
hydrogen and oxygen atoms
Explanation:
this is because they are non metals and there will be sharing of electrons between the two atoms forming the bond
It can possible be you're arteries or also you're intestines with is large and small.
Answer:
Atmospheric nitrogen is not heavier than chemical nitrogen, largely because “chemical nitrogen” is ultimately derived from atmospheric nitrogen. On the other hand, you could be asking why the atomic mass of nitrogen is not the same as the mass of nitrogen gas; that's because gaseous nitrogen is diatomic, .
Explanation:
This is from Google.
Hope this helps :))
its me again this is how you find the answer. note: i dont have the periodic table to see the exact atomic mass to find the molar mass however this is the answer:
so the actual formula is Mg(OH) with a 2 as a subscript because there are 2 Mg. so with Mg(OH)2 the Molar mass is 58.32g/mol. 58.32 g/mol x 7.1x1024 = 4.1x1026g