In chemical formulas, there are often subscript numbers (such as the 2 in H2O, or the 6, 12, and 6 in C6H12O6).
1 answer:
Answer : The correct option is, Subscript numbers tell us how many of the element to their upper-left there are in the molecule.
Explanation :
Subscript number : It indicates that the total number of atoms of an element present in a molecule.
While witting a chemical formula, first we have to write the symbol of an element and then write the number in the bottom of the symbol.
For example :
is the chemical formula of the glucose molecule. The glucose molecule is made up of six carbon atoms, twelve hydrogen atoms and 6 oxygen atoms.
The number 6 of carbon atom is written after and in the bottom (lower-right) of the symbol of carbon element (C). Similarly, the number 12 is written lower-right of the symbol of hydrogen element (H) and the number 6 is written lower-right of the symbol of oxygen element (O).
Therefore, the subscript numbers tell us how many of the element to their upper-left there are in the molecule.
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Aluminum hydroxide can behave as a base and neutralize sulfuric acid
as in the following equation:
(Balanced)
(a)
. Thus the ratio between the number of moles of the two reactants available:
The value of this ratio required to lead to a complete reaction is derived from coefficients found in the balanced equation:
The ratio for the complete reaction is smaller than that of the reactants available, indicating that the species represented on the numerator, , is in excess while the one on the denominator,
, serves as the limiting reagent.
(b)
The quantity of water produced is dependent on the amount of limiting reactants available. of sulfuric acid is supplied in this reaction as the limiting reagent.
moles of water molecules are produced for every
moles of sulfuric acid consumed. The reaction would thus give rise to
of water molecules, which have a mass of
.
(c)
(d)
The quantity of , the reactant in excess, is dependent on the number of moles of this species consumed in the reaction and thus the quantity of the limiting reagent available. The consumption of every
moles of sulfuric acid, the limiting reagent, removes
moles of aluminum hydroxide
from the solution.
of sulfuric acid is initially available as previously stated such that
, or
, of
would be eventually consumed.
of
would thus be in excess by the end of the reaction process.
Answer:
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