Answer: A hypothesis is generally based upon either someone else's observation or on previous studies.
Explanation: They just keep testing it to make sure it's <em>always </em>true.
The mass of water is calculated as follows
find the moles of each reagent
that is moles = mass/molar mass
for H2s = 84.7/ 34= 2.485 moles
O2 = 78.4 / 32 = 2.45 moles
since 2 moles of H2S react with 3 moles of O2 therefore 2.45 moles of oxygen will be used up therefore O2 is the limiting reagent and H2S is in excess
2H2S + 3O2 ----->2So2 + 2H2O
by use of mole ratio between O2 and H20 which is 3:2 the moles of H2O is therefore = 2.45 x2/3= 1.63 moles of H2O
mass of H2O = moles x molar mass
= 1.63 g x 18g/mol = 29.4 g
We know that
1) empirical formula of a compound is the representation of a molecules with the elements in simplest mole ratio.
2) the molar mass is the actual proportion of moles of elements present in a molecule
3) there is a simple ratio between the molar mass and empirical mass a molecule
Now let us solve each problem
1) empirical formula of 
will be 
2) empirical formula of 
will be
3) empirical formula of 
will be 
4) the molecular formula will be :
the molecular formula = 4 X empirical formula = 4 X CO = 
5) the mole ratio of Cl and Cr is 
empirical formula will be 
The type of substance that is most likely to contain a covalent bond is ONE THAT IS COMPOSED OF ONLY NON METALS.
Covalent bond is a type of chemical bond in which electron pairs are shared among the participating elements in order to achieve the octet form. Covalent bond is usually found among non metals.
